1.0.0.3 false Statement Of Income Interest Based Revenue (USD $) In Millions, except Share data in Thousands false 1 $ false false iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 iso4217_USD_per_shares Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares 0 shares Standard http://www.xbrl.org/2003/instance shares 0 false 2 $ false false iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 iso4217_USD_per_shares Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares 0 shares Standard http://www.xbrl.org/2003/instance shares 0 false 3 $ false false iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 iso4217_USD_per_shares Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares 0 shares Standard http://www.xbrl.org/2003/instance shares 0 5 3 us-gaap_FeesAndCommissionsAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false No definition available. false 6 4 us-gaap_FeesAndCommissionsFiduciaryAndTrustActivities us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 true true 3276000000 3276 false false 2 true true 3745000000 3745 false false 3 true true 3388000000 3388 false false No definition available. No authoritative reference available. false 7 4 us-gaap_AssetManagementFees us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 824000000 824 false false 2 false true 1028000000 1028 false false 3 false true 1141000000 1141 false false No definition available. No authoritative reference available. false 8 4 stt_TradingServicesRevenue stt false credit duration monetary Trading services review from trading of foreign currencies for customers; changes in the fair value of derivative instruments... false false false false false false false false false 1 false true 1094000000 1094 false false 2 false true 1467000000 1467 false false 3 false true 1152000000 1152 false false Trading services review from trading of foreign currencies for customers; changes in the fair value of derivative instruments held in connection with trading activities; equity trading as agent for customers; and electronic trading for customers. No authoritative reference available. false 9 4 us-gaap_InvestmentBankingAdvisoryBrokerageAndUnderwritingFeesAndCommissions us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 570000000 570 false false 2 false true 1230000000 1230 false false 3 false true 681000000 681 false false No definition available. No authoritative reference available. false 10 4 us-gaap_FeesAndCommissionsOther us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 171000000 171 false false 2 false true 277000000 277 false false 3 false true 271000000 271 false false No definition available. No authoritative reference available. false 11 4 us-gaap_FeesAndCommissions us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 5935000000 5935 false false 2 false true 7747000000 7747 false false 3 false true 6633000000 6633 false false No definition available. No authoritative reference available. true 12 3 us-gaap_InterestIncomeExpenseNetAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false No definition available. false 13 4 us-gaap_InterestIncomeOperating us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 3286000000 3286 false false 2 false true 4879000000 4879 false false 3 false true 5212000000 5212 false false No definition available. No authoritative reference available. false 14 4 us-gaap_InterestExpense us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 722000000 722 false false 2 false true 2229000000 2229 false false 3 false true 3482000000 3482 false false No definition available. No authoritative reference available. false 15 4 us-gaap_InterestIncomeExpenseNet us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 2564000000 2564 false false 2 false true 2650000000 2650 false false 3 false true 1730000000 1730 false false No definition available. No authoritative reference available. true 16 3 us-gaap_MarketableSecuritiesGainLossAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false No definition available. false 17 4 us-gaap_AvailableForSaleSecuritiesGrossRealizedGainsLossesSaleProceeds us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 368000000 368 false false 2 false true 68000000 68 false false 3 false true 7000000 7 false false No definition available. No authoritative reference available. false 18 4 us-gaap_MarketableSecuritiesRealizedGainLossOtherThanTemporaryImpairmentsAmount us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -1155000000 -1155 false false 2 false true -122000000 -122 false false 3 false true -34000000 -34 false false No definition available. No authoritative reference available. false 19 4 stt_NoncreditPortionOfOtherThanTemporaryImpairments stt false debit duration monetary Noncredit portion of other-than-temporary impairments false false false false false false false false false 1 false true 928000000 928 false false 2 false true 0 0 false false 3 false true 0 0 false false Noncredit portion of other-than-temporary impairments No authoritative reference available. false 20 4 us-gaap_MarketableSecuritiesGainLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 141000000 141 false false 2 false true -54000000 -54 false false 3 false true -27000000 -27 false false No definition available. No authoritative reference available. true 21 3 us-gaap_GainsLossesOnSalesOfAssets us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 0 0 false false 2 false true 350000000 350 false false 3 false true 0 0 false false No definition available. No authoritative reference available. false 22 3 us-gaap_Revenues us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 8640000000 8640 false false 2 false true 10693000000 10693 false false 3 false true 8336000000 8336 false false No definition available. No authoritative reference available. true 23 3 us-gaap_ProvisionForLoanAndLeaseLosses us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 149000000 149 false false 2 false true 0 0 false false 3 false true 0 0 false false No definition available. No authoritative reference available. false 24 3 us-gaap_OperatingCostsAndExpensesAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false No definition available. false 25 4 us-gaap_LaborAndRelatedExpense us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 3037000000 3037 false false 2 false true 3842000000 3842 false false 3 false true 3256000000 3256 false false No definition available. No authoritative reference available. false 26 4 us-gaap_CommunicationsAndInformationTechnology us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 656000000 656 false false 2 false true 633000000 633 false false 3 false true 546000000 546 false false No definition available. No authoritative reference available. false 27 4 us-gaap_FloorBrokerageExchangeAndClearanceFees us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 583000000 583 false false 2 false true 644000000 644 false false 3 false true 619000000 619 false false No definition available. No authoritative reference available. false 28 4 us-gaap_OccupancyNet us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 475000000 475 false false 2 false true 465000000 465 false false 3 false true 408000000 408 false false No definition available. No authoritative reference available. false 29 4 us-gaap_LegalFees us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 250000000 250 false false 2 false true 0 0 false false 3 false true 600000000 600 false false No definition available. No authoritative reference available. false 30 4 us-gaap_OtherNoninterestExpense us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 0 0 false false 2 false true 450000000 450 false false 3 false true 0 0 false false No definition available. No authoritative reference available. false 31 4 us-gaap_RestructuringCharges us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 0 0 false false 2 false true 306000000 306 false false 3 false true 0 0 false false No definition available. No authoritative reference available. false 32 4 us-gaap_BusinessCombinationAcquisitionRelatedCosts us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 49000000 49 false false 2 false true 115000000 115 false false 3 false true 198000000 198 false false No definition available. No authoritative reference available. false 33 4 us-gaap_ProfessionalFees us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 264000000 264 false false 2 false true 360000000 360 false false 3 false true 236000000 236 false false No definition available. No authoritative reference available. false 34 4 us-gaap_AmortizationOfIntangibleAssets us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 136000000 136 false false 2 false true 144000000 144 false false 3 false true 92000000 92 false false No definition available. No authoritative reference available. false 35 4 us-gaap_OtherExpenses us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 516000000 516 false false 2 false true 892000000 892 false false 3 false true 478000000 478 false false No definition available. No authoritative reference available. false 36 4 us-gaap_NoninterestExpense us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 5966000000 5966 false false 2 false true 7851000000 7851 false false 3 false true 6433000000 6433 false false No definition available. No authoritative reference available. true 37 3 stt_IncomeLossBeforeProvisionForIncomeTaxesDiscontinuedOperationsAndExtraordinaryItem stt false credit duration monetary Income (Loss) Before Provision for Income Taxes, Discontinued Operations and Extraordinary Item false false false false false false false false false 1 false true 2525000000 2525 false false 2 false true 2842000000 2842 false false 3 false true 1903000000 1903 false false Income (Loss) Before Provision for Income Taxes, Discontinued Operations and Extraordinary Item No authoritative reference available. true 38 3 us-gaap_IncomeTaxExpenseBenefit us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 722000000 722 false false 2 false true 1031000000 1031 false false 3 false true 642000000 642 false false No definition available. No authoritative reference available. false 39 3 us-gaap_IncomeLossBeforeExtraordinaryItemsAndCumulativeEffectOfChangeInAccountingPrinciple us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 1803000000 1803 false false 2 false true 1811000000 1811 false false 3 false true 1261000000 1261 false false No definition available. No authoritative reference available. true 40 3 us-gaap_ExtraordinaryItemNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true -3684000000 -3684 false false 2 false true 0 0 false false 3 false true 0 0 false false No definition available. No authoritative reference available. false 41 3 us-gaap_NetIncomeLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true -1881000000 -1881 false false 2 false true 1811000000 1811 false false 3 false true 1261000000 1261 false false No definition available. No authoritative reference available. true 42 3 stt_IncomeLossBeforeExtraordinaryItemsAvailableToCommonShareholders stt false credit duration monetary Income (Loss) before Extraordinary Items Available to Common Shareholders false false false false false false false false false 1 false true 1640000000 1640 false false 2 false true 1789000000 1789 false false 3 false true 1261000000 1261 false false Income (Loss) before Extraordinary Items Available to Common Shareholders No authoritative reference available. false 43 3 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 true true -2044000000 -2044 false false 2 true true 1789000000 1789 false false 3 true true 1261000000 1261 false false No definition available. No authoritative reference available. false 44 3 us-gaap_EarningsPerShareBasicOtherDisclosuresAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false No definition available. false 45 4 us-gaap_IncomeLossBeforeExtraordinaryItemsAndCumulativeEffectOfChangeInAccountingPrinciplePerBasicShare us-gaap true na duration decimal No definition available. false false false false false false false false true 1 true true 3.50 3.50 false false 2 true true 4.32 4.32 false false 3 true true 3.49 3.49 false false No definition available. No authoritative reference available. false 46 4 us-gaap_IncomeLossBeforeExtraordinaryItemsAndCumulativeEffectOfChangeInAccountingPrinciplePerDilutedShare us-gaap true na duration decimal No definition available. false false false false false false false false true 1 true true 3.46 3.46 false false 2 true true 4.30 4.30 false false 3 true true 3.45 3.45 false false No definition available. No authoritative reference available. false 47 3 us-gaap_EarningsPerShareAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false No definition available. false 48 4 us-gaap_EarningsPerShareBasic us-gaap true na duration decimal No definition available. false false false false false false false false true 1 true true -4.32 -4.32 false false 2 true true 4.32 4.32 false false 3 true true 3.49 3.49 false false No definition available. No authoritative reference available. false 49 4 us-gaap_EarningsPerShareDiluted us-gaap true na duration decimal No definition available. false false false false false false false false true 1 true true -4.31 -4.31 false false 2 true true 4.30 4.30 false false 3 true true 3.45 3.45 false false No definition available. No authoritative reference available. false 50 3 us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false No definition available. false 51 4 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic us-gaap true na duration shares No definition available. false false false false false false false false false 1 false true 470602000 470602 false false 2 false true 413182000 413182 false false 3 false true 360675000 360675 false false No definition available. No authoritative reference available. false 52 4 us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding us-gaap true na duration shares No definition available. false false false false false false false false false 1 false true 474003000 474003 false false 2 false true 416100000 416100 false false 3 false true 365488000 365488 false false No definition available. No authoritative reference available. false false 3 48 false Millions Thousands Hundreds false true