2.2.0.25truefalse42402 - Disclosure - Line of Business Information (Summary of Line of Business Results) (Details)truefalsefalse1falsefalseUSDfalsefalse1/1/2010 - 12/31/2010 USD ($) USD ($) / shares $Duration_1_1_2010_To_12_31_2010http://www.sec.gov/CIK0000093751duration2010-01-01T00:00:002010-12-31T00:00:00Unit15Standardhttp://xbrl.us/us-types/2009-01-31sqftxbrlus0Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0Unit14Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2falsefalseUSDfalsefalse1/1/2009 - 12/31/2009 USD ($) USD ($) / shares $Duration_1_1_2009_To_12_31_2009http://www.sec.gov/CIK0000093751duration2009-01-01T00:00:002009-12-31T00:00:00Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Divide http://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$3falsefalseUSDfalsefalse1/1/2008 - 12/31/2008 USD ($) USD ($) / shares $Duration_1_1_2008_To_12_31_2008http://www.sec.gov/CIK0000093751duration2008-01-01T00:00:002008-12-31T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$2false0us-gaap_FeesAndCommissionsFiduciaryAndTr ustActivitiesus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse39380000003938000000falsetruefalsefalsefalse2truefalsefalse33340000003334000000falsetruefalsefalsefalse3truefalsefalse37980000003798000000falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryIncome from services rendered by trust departments or by any consolidated subsidiaries acting in a fiduciary capacity, including fees earned for (1) acting as an agent for fiduciary placement and loans and (2) custody or investment advisory services when such fees are not separately billed to the customer. This item excludes commissions and fees received for the accumulation or disbursement of funds deposited to Individual Retirement or Keogh plan accounts when such are not handled by the reporting entity's trust department.Reference 1: http://www. xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Article 9 falsefalse3false0us-gaap_AssetManagementFeesus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefal se829000000829000000falsefalsefalsefalsefalse2truefalsefalse766000000766000000falsefalsefalsefalsefalse3truefalsefalse975000000975000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryRevenue recognized in the period for (1) performance (incentive) fees based on the investment results achieved for management of certain institutional accounts and hedge funds, (2) schedule-based fees earned for management of mutual funds and closed-end funds, based either on average daily net assets or on a combination of the average daily net assets and gross income, and (3) othe r investment management and advisory fees.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-BRD -Chapter 4 -Paragraph 9, 51, 59 -IssueDate 2006-05-01 falsefalse4false0stt_TradingServicesRevenuesttfalsecreditdurationTrading Services Revenuefalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsef alse11060000001106000000falsefalsefalsefalsefalse2truefalsefalse10940000001094000000falsefalsefalsefalsefalse3truefalse< /IsRatio>false14670000001467000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTrading Services RevenueNo authoritative reference available.falsefalse5false0us-gaap_InvestmentBankingAdvisoryBrokerageAndUnderwritingFeesAndCommiss ionsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse318000000318000000falsefalsefalsefalsefalse2truefalsefalse570000000570000000falsefalsefalsefalsefalse3truefalsefalse12300000001230000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFees and commissions from underwriting securities, private placements of securities, investment advisory and management services, merger and acquisition services, and other related consulting fees. Include fees and commissions from securities brokerage activities, from the sale and servicing of mutual funds, from the purchase and sale of securities and money market instruments where the bank is acting as agent for other banks or customers, and from the lending of securities owned by the bank or by bank customers (exclusive of trading revenue). Also includes the bank's proportionate share of the income or loss before extraordinary items and other adjustments from its investments in: unconsolidated subsidiaries, associated companies and corporate joint ventures, unincorporated joint ventures, general partnerships, and limited partnerships over which the bank exercises significant influence and that are principally engaged in investment banking, advisory, brokerage, or securities underwriting activities.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 13 -Subparagraph c -Subsection II Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Subparagraph b -Article 9 falsefalse6false0us-gaap_FeesAndCommissionsOtherus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse349000000349000000falsefalsefalsefalsefalse2truefalsefalse171000000171000000falsefalsefalsefalsefalse3truefalsefalse277000000277000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFee and commission revenue earned from sources not otherwise specified in the existing taxonomy.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number EITF85-24-1 falsefalse7false0us-gaap_FeesAndCommissionsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse65400000006540000000falsefalsefalsefalsefalse2truefalsefalse59350000005935000000falsefalsefalsefalsefalse3truefalsefalse77470000007747000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal fees and commissions earned from providing services such as leasing of space or maintaining: (1) depositor accounts; (2) transfer agent; (3) fiduciary and trust; (4) brokerage and underwriting; (5) mortgage; (6) credit cards; (7) correspondent clearing; and (8) other such services and activities performed for others. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 13 -Subsection II Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Article 9 falsefalse8false0us-gaap_InterestIncomeExpenseNetus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse26990000002699000000falsefalsefalsefalsefalse2truefalsefalse25640000002564000000falsefalsefalsefalsefalse3truefalsefalse26500000002650000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of net interest income or expense derived from banking operations.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 10 -Article 9 falsefalse9false0us-gaap_MarketableSecuritiesGainLossus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse-286000000-286000000falsefalsefalsefalsefalse2truefalsefalse141000000141000000falsefalsefalsefalsefalse3truefalsefalse-54000000-54000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThis item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain or loss of held-to-maturity securities transferred to the trading security category and the cumu lative unrealized gain or loss which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any losses recognized for other than temporary impairments of the subject investments in debt and equity securities.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 13, 22 falsefalse10false0us-gaap_GainLossOnSaleOfStockInSubsidiaryOrEquityMethodInvesteeus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse00&nbsp;falsefalsefalsefalsefalse3truefalsefalse350000000350000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryGain or loss on entity's disposition of equity in securities of subsidiaries or 50 percent or less owned persons. Reflects the difference in the parent company's carrying amount of the equity interest in the subsidiary (or equity method investee) immediately before and after all st ock transactions.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Subparagraph g -Article 9 falsefalse11false0us-gaap_Revenuesus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse89530000008953000000falsefalsefalsefalsefalse2truefalsefalse86400000008640000000falsefalsefalsefalsefalse3truefalsefalse1069300000010693000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Article 5 falsefalse12false0us-gaap_ProvisionForLoanAndLeaseLossesus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse2500000025000000falsefalsefalsefalsefalse2truefalsefalse149000000149000000falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe sum of the periodic provision charged to operations, based on an assessment of the uncollectibility of the loan and lease portfolio, the offset to which is either added to or deducted from the allowance account for the purpose of reducing loan receivable and leases to an amount that approximates their net realizable value (the amount expected to be collected). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 5 -Paragraph 168, 169, 170 -IssueDate 2006-05-01 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 9 falsefalse13false0us-gaap_OperatingCostsAndExpensesus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse61830000006183000000falsefalsefalsefalsefalse2truefalsefalse56670000005667000000falsefalsefalsefalsefalse3truefalsefalse67800000006780000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryGenerally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Excludes Selling, General and Administrative Expense.No authoritative reference available.fals efalse14false0stt_SecuritiesLendingChargessttfalsedebitdurationSecurities Lending Chargesfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse< NumericAmount>414000000414000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySecurities Lending ChargesNo authoritative reference available.falsefalse15false0stt_ProvisionForLegalExposuresttfalsedebitdurationProvision for legal exposurefalsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2truefalsefalse250000000250000000falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryProvision for legal exposureNo authoritative reference available.falsefalse16false0us-gaap_ProvisionForOtherLossesus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3truefalsefalse450000000450000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe provision charged to earnings in the period, the offset to which is either added to or deducted from the allowance account, for the purpose of reducing receivables, other than loans, leases, or credit losses, to an amount that approximates their net realizable value (the amount expected to be collected); includes provision for losses associated with foreclosed assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 5 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 9 falsefalse17false0us-gaap_RestructuringAndRelatedCostExpectedCostus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse156000000156000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3 truefalsefalse306000000306000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount expected to be charged against earnings in the current and future periods for the specified restructuring cost.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 146 -Paragraph 20 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 95-3 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 5 -Section P -Subsection 3, 4 falsefalse18false0stt_CustomerIndemnificationObligationsttfalsedebitdurationCustomer indemnification obligationfalsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3truefalsefalse200000000200000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCustomer indemnification obligationNo authoritative reference available.falsefalse19false0us-gaap_BusinessCombinationAcquisitionRelatedCostsus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse8900000089000000falsefalsefalsefalsefalse2truefalsefalse4900000049000000falsefalsefalsefalsefalse3truefalsefalse115000000115000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThis element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 141R -Paragraph 59 falsefalse20false0us-gaap_NoninterestExpenseus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse68420000006842000000falsefalsefalsefalsefalse2truefalsefalse59660000005966000000falsefalsefalsefalsefalse3truefalsefalse78510000007851000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal aggregate amount of all noninterest expense.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 14 -Subsection II Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 14 -Article 9 falsefalse21false0us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestmentsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse20860000002086000000falsefalsefalsefalsefalse2truefalsefalse25250000002525000000falsefalsefalsefalsefalse3truefalsefalse28420000002842000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySum of operating profit and nonoperating income (expense) before income (loss) from equity method investments, income taxes, extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest.Reference 1: ht tp://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Subparagraph 1(i) -Article 4 truefalse22false0stt_AverageAssetsInBillionssttfalsedebitdurationAverage Assets (In Billions)falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse152000000000152000000000falsefalsefalsefalsefalse2truefalsefalse146800000000146800000000falsefalsefalsefalsefalse< Cell>3truefalsefalse161700000000161700000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAverage Assets (In Billions)No authoritative reference available.falsefalse23false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.statestreet.com/taxonomy/role/disclosurelineofbusinessinformationsummaryoflineofbusinessresultsdetails1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse4falsefalseUSDtruefalse{us-gaap_StatementBusinessSegmentsAxis} : Investment Servicing [Member] 1/1/2010 - 12/31/2010 USD ($) $Duration_1_1_2010_To_12_31_201032http://www.sec.gov/CIK0000093751duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseInvestment Servicing [Member]us-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldistt_InvestmentServicingMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$5falsefalseUSDtruefalse{us-gaap_StatementBusinessSegmentsAxis} : Investment Servicing [Member] 1/1/2009 - 12/31/2009 USD ($) $Duration_1_1_2009_To_12_31_20094http://www.sec.gov/CIK0000093751duration2009-01-01T00:00:002009-12-31T00:00:00falsefalseInvestment Servicing [Member]us-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldistt_InvestmentServicingMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$6falsefalseUSDtruefalse{us-gaap_StatementBusinessSegmentsAxis} : Investment Servicing [Member] 1/1/2008 - 12/31/2008 USD ($) $Duration_1_1_2008_To_12_31_20084http://www.sec.gov/CIK0000093751duration2008-01-01T00:00:002008-12-31T00:00:00falsefalseInvestment Servicing [Member]us-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldistt_InvestmentServicingMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$OthernaNo definition available.No authoritative reference available.falsefalse24false0us-gaap_FeesAndCommissionsFiduciaryAndTrustActivitiesus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse3938000000393800 0000falsefalsefalsefalsefalse2truefalsefalse33340000003334000000falsefalsefalsefalsefalse3truefalsefalse37980000003798000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryIncome from services rendered by trust departments or by any consolidated subsidiaries acting in a fiduciary capacity, including fees earned for (1) acting as an agent for fiduciary placement and loans and (2) custody or investment advisory services when such fees are not separately billed to the customer. This item excludes commissions and fees received for the accumulation or disbursement of funds deposited to Individual Retirement or Keogh plan accounts when suc h are not handled by the reporting entity's trust department.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Article 9 falsefalse25false0us-gaap_AssetManagementFeesus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1falsefalsef alse00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse00&nbsp;falsefalsefalsefalsefalse3falsefalsefalse00&nbsp;falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryRevenue recognized in the period for (1) performance (incentive) fees based on the investment results achieved for management of certain institutional accounts and hedge funds, (2) schedule-based fees earned for management of mutual funds and closed-end funds, based either on average daily net assets or on a combination of the average daily net ass ets and gross income, and (3) other investment management and advisory fees.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-BRD -Chapter 4 -Paragraph 9, 51, 59 -IssueDate 2006-05-01 falsefalse26false0stt_TradingServicesRevenuesttfalsecreditdurationTrading Services Revenuefalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalse false11060000001106000000falsefalsefalsefalsefalse2truefalsefalse10940000001094000000falsefalsefalsefalsefalse3truefalse false14670000001467000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTrading Services RevenueNo authoritative reference available.falsefalse27false0us-gaap_InvestmentBankingAdvisoryBrokerageAndUnderwritingFeesAndCommi ssionsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse265000000265000000falsefalsefalsefalsefalse2truefalsefalse387000000387000000falsefalsefalsefalsefalse3truefalsefalse900000000900000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFees and commissions from underwriting securities, private placements of securities, investment advisory and management services, merger and acquisition services, and other related consulting fees. Include fees and commissions from securities brokerage activities, from the sale and servicing of mutual funds, from the purchase and sale of securities and money market instruments where the bank is acting as agent for other banks or customers, and from the lending of securities owned by the bank or by bank customers (exclusive of trading revenue). Also includes the bank's proportionate share of the income or loss before extraordinary items and other adjustments from its investments in: unconsolidated subsidiaries, associated companies and corporate joint ventures, unincorporated joint ventures, general partnerships, and limited partnerships over which the bank exercises significant influence and that are principally engaged in investment banking, advisory, brokerage, or securities underwriting activities.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 13 -Subparagraph c -Subsection II Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Subparagraph b -Article 9 falsefalse28false0us-gaap_FeesAndCommissionsOtherus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse225000000225000000falsefalsefalsefalsefalse2truefalsefalse7200000072000000falsefalsefalsefalsefalse3true falsefalse200000000200000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFee and commission revenue earned from sources not otherwise specified in the existing taxonomy.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number EITF85-24-1 falsefalse29false0us-gaap_FeesAndCommissionsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse55340000005534000000falsefalsefalsefalsefalse2truefalsefalse48870000004887000000falsefalsefalsefalsefalse3true< IsRatio>falsefalse63650000006365000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal fees and commissions earned from providing services such as leasing of space or maintaining: (1) depositor accounts; (2) transfer agent; (3) fiduciary and trust; (4) brokerage and underwriting; (5) mortgage; (6) credit cards; (7) correspondent clearing; and (8) other such services and activities performed for others.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 13 -Subsection II Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Article 9 falsefalse30false0us-gaap_InterestIncomeExpenseNetus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse26330000002633000000falsefalsefalsefalsefalse2truefalsefalse24890000002489000000falsefalsefalsefalsefalse3true< IsRatio>falsefalse24800000002480000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of net interest income or expense derived from banking operations.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 10 -Article 9 falsefalse31false0us-gaap_MarketableSecuritiesGainLossus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalse< DisplayZeroAsNone>false5800000058000000falsefalsefalsefalsefalse2truefalsefalse141000000141000000falsefalsefalsefalsefalse3truefalsefalse-54000000-54000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThis item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain or loss of held-to-maturity securities transferred to the trading security category and the cumulat ive unrealized gain or loss which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any losses recognized for other than temporary impairments of the subject investments in debt and equity securities.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 13, 22 falsefalse32false0us-gaap_GainLossOnSaleOfStockInSubsidiaryOrEquityMethodInvesteeus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse00&nbsp;falsefalsefalsefalsefalse3falsefalsefalse00&nbsp;falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryGain or loss on entity's disposition of equity in securities of subsidiaries or 50 percent or less owned persons. Reflects the difference in the parent company's carrying amount of the equity interest in the subsidiary (or equity method investee) immediately before and a fter all stock transactions.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Subparagraph g -Article 9 falsefalse33false0us-gaap_Revenuesus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse82250000008225000000falsefalsefalsefalsefalse2truefalsefalse75170000007517000000falsefalsefalsefalsefalse3truefalsefalse87910000008791000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Article 5 falsefalse34false0us-gaap_ProvisionForLoanAndLeaseLossesus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse2500000025000000falsefalsefalsefalsefalse2truefalsefalse148000000148000000falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe sum of the periodic provision charged to operations, based on an assessment of the uncollectibility of the loan and lease portfolio, the offset to which is either added to or deducted from the allowance account for the purpose of reducing loan receivable and leases to an amount that approximates their net realizable value (the amount expected to be collected). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 5 -Paragraph 168, 169, 170 -IssueDate 2006-05-01 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 9 falsefalse35false0us-gaap_OperatingCostsAndExpensesus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse54300000005430000000falsefalsefalsefalsefalse2truefalsefalse49200000004920000000falsefalsefalsefalsefalse3truefalsefalse56990000005699000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryGenerally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Excludes Selling, General and Administrative Expense.No authoritative reference available.fals efalse36false0stt_SecuritiesLendingChargessttfalsedebitdurationSecurities Lending Chargesfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse< NumericAmount>7500000075000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySecurities Lending ChargesNo authoritative reference available.falsefalse37false0stt_ProvisionForLegalExposuresttfalsedebitdurationProvision for legal exposurefalsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalse falsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryProvision for legal exposureNo authoritative reference available.falsefalse38false0us-gaap_ProvisionForOtherLossesus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe provision charged to earnings in the period, the offset to which is either added to or deducted from the allowance account, for the purpose of reducing receivables, other than loans, leases, or credit losses, to an amount that approximates their net realizable value (the amount expected to be collected); includes provision for losses associated with foreclosed assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 5 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 9 falsefalse39false0us-gaap_RestructuringAndRelatedCostExpectedCostus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3 falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount expected to be charged against earnings in the current and future periods for the specified restructuring cost.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 146 -Paragraph 20 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 95-3 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 5 -Section P -Subsection 3, 4 falsefalse40false0stt_CustomerIndemnificationObligationsttfalsedebitdurationCustomer indemnification obligationfalsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCustomer indemnification obligationNo authoritative reference available.falsefalse41false0us-gaap_BusinessCombinationAcquisitionRela tedCostsus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00 falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThis element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 141R -Paragraph 59 falsefalse42false0us-gaap_NoninterestExpenseus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse55050000005505000000falsefalsefalsefalsefalse2truefalsefalse49200000004920000000falsefalsefalsefalsefalse3truefalsefalse56990000005699000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal aggregate amount of all noninterest expense.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 14 -Subsection II Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 14 -Article 9 falsefalse43false0us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestmentsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse26950000002695000000falsefalsefalsefalsefalse2truefalsefalse24490000002449000000falsefalsefalsefalsefalse3truefalsefalse30920000003092000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySum of operating profit and nonoperating income (expense) before income (loss) from equity method investments, income taxes, extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest.Reference 1: ht tp://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Subparagraph 1(i) -Article 4 truefalse44false0stt_PreTaxMarginsttfalsenadurationPre-tax marginfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truetrue false0.330.33falsefalsefalsefalsefalse2truetruefalse0.330.33falsefalsefalsefalsefalse3truetruefalse0.350.35falsefalsefalsefalsefalseOtherus-types:percentItemTypepurePre-tax marginNo authoritative reference available.falsefalse45false0stt_AverageAssetsInBillionssttfalsedebitdurationAverage Assets (In Billions)falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse148500000000148500000000falsefalsefalsefalsefalse2truefalsefalse143700000000143700000000falsefalsefalsefalsefalse3truefalsefalse158300000000158300000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAverage Assets (In Billions)No authoritative reference available.falsefalse46false0natruenanaNo definition available.falsetruefalsefalsefa lsefalsefalsefalsefalsefalsehttp://www.statestreet.com/taxonomy/role/disclosurelineofbusinessinformationsummaryoflineofbusinessresultsdetails1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse7fa lsefalseUSDtruefalse{us-gaap_StatementBusinessSegmentsAxis} : Investment Management [Member] 1/1/2010 - 12/31/2010 USD ($) $Duration_1_1_2010_To_12_31_201022http://www.sec.gov/CIK0000093751duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseInvestment Management [Member]us-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldistt_InvestmentManagementMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217 USDiso42170Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$8falsefalseUSDtruefalse{us-gaap_StatementBusinessSegmentsAxis} : Investment Management [Member] 1/1/2009 - 12/31/2009 USD ($) $Duration_1_1_2009_To_12_31_200922http://www.sec.gov/CIK0000093751duration2009-01-01T00:00:002009-12-31T00:00:00falsefalseInvestment Management [Member]us-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldistt_InvestmentManagementMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217 USDiso42170Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$9falsefalseUSDtruefalse{us-gaap_StatementBusinessSegmentsAxis} : Investment Management [Member] 1/1/2008 - 12/31/2008 USD ($) $Duration_1_1_2008_To_12_31_20083http://www.sec.gov/CIK0000093751duration2008-01-01T00:00:002008-12-31T00:00:00falsefalseInvestment Management [Member]us-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldistt_InvestmentManagementMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217< /MeasureSchema>USDiso42170Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$OthernaNo definition available.No authoritative reference available.falsefalse4 7false0us-gaap_FeesAndCommissionsFiduciaryAndTrustActivitiesus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryIncome from services rendered by trust departments or by any consolidated subsidiaries acting in a fiduciary capacity, including fees earned for (1) acting as an agent for fiduciary placement and loans and (2) custody or investment advisory services when such fees are not separately billed to the customer. This item excludes commissions and fees received for the accumulation or disbursement of funds deposited to Individual Retirement or Keogh plan accounts when such are not handled by the reporting entity's trus t department.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Article 9 falsefalse48false0us-gaap_AssetManagementFeesus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefa lse829000000829000000falsefalsefalsefalsefalse2truefalsefalse766000000766000000falsefalsefalsefalsefalse3truefalsefalse975000000975000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryRevenue recognized in the period for (1) performance (incentive) fees based on the investment results achieved for management of certain institutional accounts and hedge funds, (2) schedule-based fees earned for management of mutual funds and closed-end funds, based either on average daily net assets or on a combination of the average daily net assets and gross income, and (3) oth er investment management and advisory fees.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-BRD -Chapter 4 -Paragraph 9, 51, 59 -IssueDate 2006-05-01 falsefalse49false0stt_TradingServicesRevenuesttfalsecreditdurationTrading Services Revenuefalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTrading Services RevenueNo authoritative reference available.falsefalse50false0us-gaap_InvestmentBankingAdvisoryBrokerageAndUnderwritingFeesAndCommissionsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse5300000053000000falsefalsefalsefalsefalse2truefalsefalse183000000183000000falsefalsefalsefalsefalse3truefalsefalse330000000330000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFees and commissions from underwriting securities, private placements of securities, investment advisory and management services, merger and acquisition services, and other related consulting fees. Include fees and commissions from securities brokerage activities, from the sale and servicing of mutual funds, from the purchase and sale of securities and money market instruments where the bank is acting as agent for other banks or customers, and from the lending of securities owned by the bank or by bank customers (exclusive of trading revenue). Also includes the bank's proportionate share of the income or loss before extraordina ry items and other adjustments from its investments in: unconsolidated subsidiaries, associated companies and corporate joint ventures, unincorporated joint ventures, general partnerships, and limited partnerships over which the bank exercises significant influence and that are principally engaged in investment banking, advisory, brokerage, or securities underwriting activities.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 13 -Subparagraph c -Subsection II Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Subparagraph b -Article 9 falsefalse51false0us-gaap_FeesAndCommissionsOtherus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse124000000124000000falsefalsefalsefalsefalse2truefalsefalse9900000099000000falsefalsefalsefalsefalse3true falsefalse8500000085000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFee and commission revenue earned from sources not otherwise specified in the existing taxonomy.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number EITF85-24-1 falsefalse52false0us-gaap_FeesAndCommissionsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse10060000001006000000falsefalsefalsefalsefalse2truefalsefalse10480000001048000000falsefalsefalsefalsefalse3true< IsRatio>falsefalse13900000001390000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal fees and commissions earned from providing services such as leasing of space or maintaining: (1) depositor accounts; (2) transfer agent; (3) fiduciary and trust; (4) brokerage and underwriting; (5) mortgage; (6) credit cards; (7) correspondent clearing; and (8) other such services and activities performed for others.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 13 -Subsection II Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Article 9 falsefalse53false0us-gaap_InterestIncomeExpenseNetus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse6600000066000000falsefalsefalsefalsefalse2truefalsefalse6800000068000000falsefalsefalsefalsefalse3true falsefalse9600000096000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of net interest income or expense derived from banking operations.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 10 -Article 9 falsefalse54false0us-gaap_MarketableSecuritiesGainLossus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalse false00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThis item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain or loss of held-to-maturity securities transferred to the trading security category and the cumulative unrealized ga in or loss which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any losses recognized for other than temporary impairments of the subject investments in debt and equity securities.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 13, 22 falsefalse55false0us-gaap_GainLossOnSaleOfStockInSubsidiaryOrEquityMethodInvesteeus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse00&nbsp;falsefalsefalsefalsefalse3falsefalsefalse00&nbsp;falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryGain or loss on entity's disposition of equity in securities of subsidiaries or 50 percent or less owned persons. Reflects the difference in the parent company's carrying amount of the equity interest in the subsidiary (or equity method investee) immediately before and a fter all stock transactions.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Subparagraph g -Article 9 falsefalse56false0us-gaap_Revenuesus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse10720000001072000000falsefalsefalsefalsefalse2truefalsefalse11160000001116000000falsefalsefalsefalsefalse3truefalsefalse14860000001486000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Article 5 falsefalse57false0us-gaap_ProvisionForLoanAndLeaseLossesus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2truefalsefalse10000001000000falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe sum of the periodic provision charged to operations, based on an assessment of the uncollectibility of the loan and lease portfolio, the offset to which is either added to or deducted from the allowance account for the purpose of reducing loan receivable and leases to an amount that approximates their net realizable value (the amount expected to be collected).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 5 -Paragraph 168, 169, 170 -IssueDate 2006-05-01 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 9 falsefalse58false0us-gaap_OperatingCostsAndExpensesus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse753000000753000000falsefalsefalsefalsefalse2truefalsefalse747000000747000000falsefalsefalsefalsefalse3truefalsefalse10760000001076000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryGenerally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Excludes Selling, General and Administrative Expense.No authoritative reference available.falsefalse59false0stt_SecuritiesLendingChargessttfalsedebitdurationSecurities Lending Chargesfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse339000000339000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySecurities Lending ChargesNo authoritative reference available.falsefalse60false0stt_ProvisionForLegalExposuresttfalsedebitdurationProvision for legal exposurefalsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2truefalsefalse250000000250000000falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryProvision for legal exposureNo authoritative reference available.falsefalse61false0us-gaap_ProvisionForOtherLossesus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse0 0falsefalsefalsefalsefalse3truefalsefalse450000000450000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe provision charged to earnings in the period, the offset to which is either added to or deducted from the allowance account, for the purpose of reducing receivables, other than loans, leases, or credit losses, to an amount that approximates their net realizable value (the amount expected to be collected); includes provision for losses associated with foreclosed assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 5 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 9 falsefalse62false0us-gaap_RestructuringAndRelatedCostExpectedCostus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3 falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount expected to be charged against earnings in the current and future periods for the specified restructuring cost.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 146 -Paragraph 20 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 95-3 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 5 -Section P -Subsection 3, 4 falsefalse63false0stt_CustomerIndemnificationObligationsttfalsedebitdurationCustomer indemnification obligationfalsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCustomer indemnification obligationNo authoritative reference available.falsefalse64false0us-gaap_BusinessCombinationAcquisitionRela tedCostsus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00 falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThis element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 141R -Paragraph 59 falsefalse65false0us-gaap_NoninterestExpenseus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse10920000001092000000falsefalsefalsefalsefalse2truefalsefalse997000000997000000falsefalsefalsefalsefalse3truefalsefalse15260000001526000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal aggregate amount of all noninterest expense.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 14 -Subsection II Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 14 -Article 9 falsefalse66false0us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestmentsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse-20000000-20000000falsefalsefalsefalsefalse2truefalsefalse118000000118000000falsefalsefalsefalsefalse3truefalsefalse-40000000-40000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySum of operating profit and nonoperating income (expense) before income (loss) from equity method investments, income taxes, extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest.Reference 1: http://w ww.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Subparagraph 1(i) -Article 4 truefalse67false0stt_PreTaxMarginsttfalsenadurationPre-tax marginfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truetrue false-0.02-0.02falsefalsefalsefalsefalse2truetruefalse0.110.11falsefalsefalsefalsefalse3truetruefalse-0.03-0.03falsefalsefalsefalsefalseOtherus-types:percentItemTypepurePre-tax marginNo authoritative reference available.falsefalse68false0stt_AverageAssetsInBillionssttfalsedebitdurationAverage Assets (In Billions)falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse35000000003500000000falsefalsefalsefalsefalse2truefalsefalse31000000003100000000falsefalsefalsefalsefalse3truefalsefalse29000000002900000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAverage Assets (In Billions)No authoritative reference available.falsefalse69false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.statestreet.com/taxonomy/role/disclosurelineofbusinessinformationsummaryoflineofbusinessresultsdetails1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse10falsefalseUSDtruefalse{us-gaap_StatementBusinessSegmentsAxis} : Divestitures [Member] 1/1/2008 - 12/31/2008 USD ($) $Duration_1_1_2008_To_12_31_20082http://www.sec.gov/CIK0000093751duration2008-01-01T00:00:002008-12-31T00:00:00falsefalseDivestitures [Member]us-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldistt_DivestituresMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalse70false0us-gaap_FeesAndCommissionsOtherus-gaaptruecreditdurationNo definition availa ble.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3truefalsefalse-8000000-8000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFee and commission revenue earned from sources not otherwise specified in the existing taxonomy.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number EITF85-24-1 falsefalse71false0us-gaap_FeesAndCommissionsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3truefalsefalse-8000000-8000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal fees and commissions earned from providing services such as leasing of space or maintaining: (1) depositor accounts; (2) transfer agent; (3) fiduciary and trust; (4) brokerage and underwriting; (5) mortgage; (6) credit cards; (7) correspondent clearing; and (8) other such services and activities performed for others.Reference 1: http://www.xbrl.org/2003 /role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 13 -Subsection II Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Article 9 falsefalse72false0us-gaap_InterestIncomeExpenseNetus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3truefalsefalse60000006000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of net interest income or expense derived from banking operations.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 10 -Article 9 falsefalse73false0us-gaap_GainLossOnSaleOfStockInSubsidiaryOrEquityMethodInvesteeus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00&nbsp;falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryGain or loss on entity's disposition of equity in securities of subsidiaries or 50 percent or less owned persons. Reflects the difference in the parent company's carrying amount of the equity interest in the subsidiary (or equity method investee) immediately before and after all stock transactions.Reference 1: http ://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Subparagraph g -Article 9 falsefalse74false0us-gaap_Revenuesus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1false< /IsNumeric>falsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3truefalsefalse-2000000-2000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.Reference 1: http://www.xbrl.org/20 03/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Article 5 falsefalse75false0us-gaap_OperatingCostsAndExpensesus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3truefalsefalse50000005000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryGenerally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Excludes Selling, General and Administrative Expense.No authoritative reference available.falsefalse76false0us-gaap_NoninterestExpenseus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3truefalsefalse50000005000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal aggregate amount of all noninterest expense.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 14 -Subsection II Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 14 -Article 9 falsefalse77false0us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestmentsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse 3truefalsefalse-7000000-7000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySum of operating profit and nonoperating income (expense) before income (loss) from equity method investments, income taxes, extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest.Reference 1: http://www.xbrl.org/2003/role/presentati onRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Subparagraph 1(i) -Article 4 truefalse78false0stt_AverageAssetsInBillionssttfalsedebitdurationAverage Assets (In Billions)falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3true falsefalse500000000500000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAverage Assets (In Billions)No authoritative reference available.falsefalse79false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.statestreet.com/taxonomy/role/disclosurelineofbusinessinformationsummaryoflineofbusinessresultsdetails1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse11falsefalseUSDtruefalse{us-gaap_StatementBusinessSegmentsAxis} : Other [Member] 1/1/2010 - 12/31/2010 USD ($) $Duration_1_1_2010_To_12_31_2010525http://www.sec.gov/CIK0000093751duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseOther [Member]us-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$12falsefalseUSDtruefalse{us-gaap_StatementBusinessSegmentsAxis} : Other [Member] 1/1/2009 - 12/31/2009 USD ($) $Duration_1_1_2009_To_12_31_200988http://www.sec.gov/CIK0000093751duration2009-01-01T00:00:002009-12-31T00:00:00falsefalseOther [Member]us-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$13falsefalseUSDtruefalse{us-gaap_StatementBusinessSegmentsAxis} : Other [Member] 1/1/2008 - 12/31/2008 USD ($) $Duration_1_1_2008_To_12_31_200852http://www.sec.gov/CIK0000093751duration2008-01-01T00:00:002008-12-31T00:00:00falsefalseOther [Member]us-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalse80false0us-gaap_InterestIncomeExpenseNetus-gaaptruecreditdurationNo definition available. falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2truefalsefalse70000007000000falsefalsefalsefalsefalse3truefalsefalse6800000068000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of net interest income or expense derived from banking operations.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 10 -Article 9 falsefalse81false0us-gaap_MarketableSecuritiesGainLossus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalse< DisplayZeroAsNone>false-344000000-344000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefal sefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThis item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain or loss of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain or los s which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any losses recognized for other than temporary impairments of the subject investments in debt and equity securities.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 13, 22 falsefalse82false0us-gaap_GainLossOnSaleOfStockInSubsidiaryOrEquityMethodInvesteeus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00&nbsp;falsefalsefalsefalsefalse2falsefalsefalse00&nbsp;falsefalsefalsefalsefalse3truefalsefalse350000000350000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryGain or loss on entity's disposition of equity in securities of subsidiaries or 50 percent or less owned persons. Reflects the difference in the parent company's carrying amount of the equity interest in the subsidiary (or equity method investee) immediately before and after all st ock transactions.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Subparagraph g -Article 9 falsefalse83false0us-gaap_Revenuesus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse-344000000-344000000falsefalsefalsefalsefalse2truefalsefalse70000007000000falsefalsefalsefalsefalse 3truefalsefalse418000000418000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). 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Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 141R -Paragraph 59 falsefalse87false0us-gaap_NoninterestExpenseus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse245000000245000000falsefalsefalsefalsefalse2truefalsefalse4900000049000000falsefalsefalsefalsefalse3truefalsefalse621000000621000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal aggregate amount of all noninterest expense.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 14 -Subsection II Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 14 -Article 9 falsefalse88false0us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestmentsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse-589000000-589000000falsetruefalsefalsefalse2truefalsefalse-42000000-42000000falsetruefalsefalsefalse3truefalsefalse-203000000-203000000falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySum of operating profit and nonoperating income (expense) before income (loss) from equity method investments, income taxes, extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest.Reference 1: http:// www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Subparagraph 1(i) -Article 4 truefalse387Line of Business Information (Summary of Line of Business Results) (Details) (USD $)NoRoundingUnKnownUnKnownUnKnowntruetrue