2.2.0.25falsefalse41102 - Disclosure - Commitments and Contingencies (Contractual Amounts of Credit-Related Off-Balance Sheet Financial Instruments) (Details)truefalseIn Millionsfalse1falsefalseUSDfalsefalse12/31/2010
USD ($)
USD ($) / shares
$As_Of_12_31_2010http://www.sec.gov/CIK0000093751instant2010-12-31T00:00:000001-01-01T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0Unit14Divide
http://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$2falsefalseUSDfalsefalse12/31/2009
USD ($)
USD ($) / shares
$As_Of_12_31_2009http://www.sec.gov/CIK0000093751instant2009-12-31T00:00:000001-01-01T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0Unit14Divide
http://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$5false0stt_AggregateFairValueOfIndemnifiedSecuritiesOnLoansttfalsedebitinstantAggregate Fair Value Of Indemnified Securities On Loanfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse334235000000334235[1]falsetruefalsefalsefalse2truefalsefalse365251000000365251[1]falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAggregate Fair Value Of Indemnified Securities On LoanNo authoritative reference available.falsefalse6false0stt_UnfundedCommitmentsToExtendCreditsttfalsedebitinstantUnfunded Commitments To Extend Creditfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel
1truefalsefalse1477200000014772falsefalsefalsefalsefalse2truefalsefalse1801400000018014falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryUnfunded Commitments To Extend CreditNo authoritative reference available.falsefalse7false0stt_AssetPurchaseAgreementssttfalsedebitinstantAsset Purchase Agreementsfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse48660000004866falsefalsefalsefalsefalse2truefalsefalse82110000008211falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAsset Purchase AgreementsNo authoritative reference available.falsefalse8false0stt_StandbyLettersOfCreditsttfalsedebitinstantStandby Letters Of Creditfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse41740000004174falsetruefalsefalsefalse2truefalsefalse47830000004783falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryStandby Letters Of CreditNo authoritative reference available.falsefalse1
Related collateral and other information is provided in the following "Securities Finance" section. 24Commitments and Contingencies (Contractual Amounts of Credit-Related Off-Balance Sheet Financial Instruments) (Details) (USD $)MillionsUnKnownUnKnownUnKnownfalsetrue
