1.0.0.3 false Statement Of Cash Flows Indirect Deposit Based Operations (USD $) In Millions 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 false 4 $ 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_NetCashProvidedByUsedInOperatingActivitiesAbstract 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 4 false false 0 0 false false No definition available. false 6 4 us-gaap_ProfitLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 true true -1285000000 -1285 false false 2 true true 1406000000 1406 false false 3 true true 1778000000 1778 false false 4 true true 3249000000 3249 false false No definition available. No authoritative reference available. false 7 4 us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract 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 4 false false 0 0 false false No definition available. false 8 5 us-gaap_DeferredIncomeTaxExpenseBenefit us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -781000000 -781 false false 2 false true -932000000 -932 false false 3 false true -1224000000 -1224 false false 4 false true -1669000000 -1669 false false No definition available. No authoritative reference available. false 9 5 us-gaap_ShareBasedCompensation us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 77000000 77 false false 2 false true 1265000000 1265 false false 3 false true 1838000000 1838 false false 4 false true 1927000000 1927 false false No definition available. No authoritative reference available. false 10 5 us-gaap_DepreciationAndAmortization us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 104000000 104 false false 2 false true 1224000000 1224 false false 3 false true 794000000 794 false false 4 false true 475000000 475 false false No definition available. No authoritative reference available. false 11 5 us-gaap_ProvisionForLoanAndLeaseLosses 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 0 0 false false 3 false true 0 0 false false 4 false true 478000000 478 false false No definition available. No authoritative reference available. false 12 5 us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal 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 -606000000 -606 false false 3 false true -2232000000 -2232 false false 4 false true -168000000 -168 false false No definition available. No authoritative reference available. false 13 5 us-gaap_GainsLossesOnExtinguishmentOfDebt us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true -73000000 -73 false false 2 false true -491000000 -491 false false 3 false true -2252000000 -2252 false false 4 false true 0 0 false false No definition available. No authoritative reference available. false 14 5 us-gaap_ProceedsFromInsuranceSettlementOperatingActivities 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 0 0 false false 3 false true 0 0 false false 4 false true -38000000 -38 false false No definition available. No authoritative reference available. false 15 5 us-gaap_AssetImpairmentCharges 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 823000000 823 false false 3 false true 1238000000 1238 false false 4 false true 437000000 437 false false No definition available. No authoritative reference available. false 16 4 us-gaap_IncreaseDecreaseInOperatingCapitalAbstract 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 4 false false 0 0 false false No definition available. false 17 5 ms_IncreaseDecreaseInCashAndSecuritiesSegregatedUnderFederalAndOtherRegulations ms false credit duration monetary The net change in the amount of cash subject to withdrawal restrictions, restricted deposits held as compensating balances,... false false false false false false false false false 1 false true 1407000000 1407 false false 2 false true 211000000 211 false false 3 false true 5001000000 5001 false false 4 false true -9334000000 -9334 false false The net change in the amount of cash subject to withdrawal restrictions, restricted deposits held as compensating balances, and cash and securities segregated in compliance with regulations (such as cash deposited in a special reserve account for the exclusive benefit of customers pursuant). No authoritative reference available. false 18 5 us-gaap_IncreaseDecreaseInFinancialInstrumentsUsedInOperatingActivities us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 2412000000 2412 false false 2 false true -26130000000 -26130 false false 3 false true 78486000000 78486 false false 4 false true -25361000000 -25361 false false No definition available. No authoritative reference available. false 19 5 us-gaap_IncreaseDecreaseInSecuritiesBorrowed us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true -2267000000 -2267 false false 2 false true -79449000000 -79449 false false 3 false true 154209000000 154209 false false 4 false true 59637000000 59637 false false No definition available. No authoritative reference available. false 20 5 us-gaap_IncreaseDecreaseInSecuritiesLoanedTransactions us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -241000000 -241 false false 2 false true 11666000000 11666 false false 3 false true -95602000000 -95602 false false 4 false true -39834000000 -39834 false false No definition available. No authoritative reference available. false 21 5 us-gaap_IncreaseDecreaseInReceivables us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 1479000000 1479 false false 2 false true -2445000000 -2445 false false 3 false true 54531000000 54531 false false 4 false true -3973000000 -3973 false false No definition available. No authoritative reference available. false 22 5 us-gaap_IncreaseDecreaseInAccountsPayable us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 11481000000 11481 false false 2 false true 818000000 818 false false 3 false true -114531000000 -114531 false false 4 false true 71092000000 71092 false false No definition available. No authoritative reference available. false 23 5 ms_IncreaseDecreaseInSecuritiesPurchasedUnderAgreementsToResell ms false credit duration monetary The net change in the beginning and end of period for investments purchased under the agreement to resell such investment... false false false false false false false false false 1 false true -16290000000 -16290 false false 2 false true -20499000000 -20499 false false 3 false true 51822000000 51822 false false 4 false true 26194000000 26194 false false The net change in the beginning and end of period for investments purchased under the agreement to resell such investment balances. No authoritative reference available. false 24 5 us-gaap_IncreaseDecreaseInPayablesUnderRepurchaseAgreements us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -10188000000 -10188 false false 2 false true 67188000000 67188 false false 3 false true -60439000000 -60439 false false 4 false true -105361000000 -105361 false false No definition available. No authoritative reference available. false 25 4 us-gaap_NetCashProvidedByUsedInOperatingActivities us-gaap true na duration monetary No definition available. false false false false false false false false false 1 false true -14165000000 -14165 false false 2 false true -45951000000 -45951 false false 3 false true 73417000000 73417 false false 4 false true -22249000000 -22249 false false No definition available. No authoritative reference available. true 27 4 ms_NetPaymentsForProceedsFromInvestingActivitiesAbstract ms false na duration string Net (payments for) proceeds from: (Investing Activities) [Abstract] 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 4 false false 0 0 false false Net (payments for) proceeds from: (Investing Activities) [Abstract] false 28 5 us-gaap_PaymentsForProceedsFromProductiveAssets us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true -107000000 -107 false false 2 false true -2877000000 -2877 false false 3 false true -1400000000 -1400 false false 4 false true -1469000000 -1469 false false No definition available. No authoritative reference available. false 29 5 us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired 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 -2160000000 -2160 false false 3 false true -174000000 -174 false false 4 false true -1169000000 -1169 false false No definition available. No authoritative reference available. false 30 5 us-gaap_ProceedsFromDivestitureOfBusinessesNetOfCashDivested 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 565000000 565 false false 3 false true 743000000 743 false false 4 false true 476000000 476 false false No definition available. No authoritative reference available. false 31 5 us-gaap_PaymentsToAcquireLoansReceivable 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 0 0 false false 3 false true 0 0 false false 4 false true -4776000000 -4776 false false No definition available. No authoritative reference available. false 32 5 us-gaap_ProceedsFromSaleOfLoansReceivable 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 0 0 false false 3 false true 0 0 false false 4 false true 5301000000 5301 false false No definition available. No authoritative reference available. false 33 5 us-gaap_PaymentsToAcquireAvailableForSaleSecurities 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 0 0 false false 3 false true 0 0 false false 4 false true -14073000000 -14073 false false No definition available. No authoritative reference available. false 34 5 us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities 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 0 0 false false 3 false true 0 0 false false 4 false true 4272000000 4272 false false No definition available. No authoritative reference available. false 35 4 us-gaap_NetCashProvidedByUsedInInvestingActivities us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -107000000 -107 false false 2 false true -4472000000 -4472 false false 3 false true -831000000 -831 false false 4 false true -11438000000 -11438 false false No definition available. No authoritative reference available. true 37 4 ms_NetPaymentsForProceedsFromFinancingActivitiesAbstract ms false na duration string Net (payments for) proceeds from: (Financing Activities) [Abstract] 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 4 false false 0 0 false false Net (payments for) proceeds from: (Financing Activities) [Abstract] false 38 5 us-gaap_ProceedsFromRepaymentsOfShortTermDebt us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -381000000 -381 false false 2 false true -7724000000 -7724 false false 3 false true -24012000000 -24012 false false 4 false true 8274000000 8274 false false No definition available. No authoritative reference available. false 39 5 ms_ProceedsFromPaymentsForDerivativeFinancingActivities ms false debit duration monetary The net cash inflow (outflow) from derivative financing activities. false false false false false false false false false 1 false true -3354000000 -3354 false false 2 false true -85000000 -85 false false 3 false true 962000000 962 false false 4 false true -859000000 -859 false false The net cash inflow (outflow) from derivative financing activities. No authoritative reference available. false 40 5 ms_ProceedsFromRepaymentsOfOtherSecuredFinancings ms false debit duration monetary The net cash inflow (outflow) associated with other secured financing. false false false false false false false false false 1 false true 12000000 12 false false 2 false true -4437000000 -4437 false false 3 false true -15246000000 -15246 false false 4 false true -24231000000 -24231 false false The net cash inflow (outflow) associated with other secured financing. No authoritative reference available. false 41 5 us-gaap_IncreaseDecreaseInDeposits us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 8600000000 8600 false false 2 false true 10860000000 10860 false false 3 false true 11576000000 11576 false false 4 false true 23099000000 23099 false false No definition available. No authoritative reference available. false 42 5 us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities 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 102000000 102 false false 3 false true 47000000 47 false false 4 false true 281000000 281 false false No definition available. No authoritative reference available. false 43 4 ms_NetProceedsFromFinancingActivitiesAbstract ms false na duration string Net proceeds from: [Abstract] 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 4 false false 0 0 false false Net proceeds from: [Abstract] false 44 5 us-gaap_ProceedsFromPaymentsToMinorityShareholders 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 0 0 false false 3 false true 1560000000 1560 false false 4 false true 265000000 265 false false No definition available. No authoritative reference available. false 45 5 us-gaap_ProceedsFromIssuanceInitialPublicOffering 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 6212000000 6212 false false 3 false true 0 0 false false 4 false true 0 0 false false No definition available. No authoritative reference available. false 46 5 ms_ProceedsFromIssuanceOfPreferredStockAndCommonStockWarrants ms false debit duration monetary Proceeds from issuance of capital stock which provides for a specific dividend that is paid to the shareholders before any... false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false true 18997000000 18997 false false 4 false true 0 0 false false Proceeds from issuance of capital stock which provides for a specific dividend that is paid to the shareholders before any dividends to common stockholders and which takes precedence over common stockholders in the event of liquidation and the cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt). No authoritative reference available. false 47 5 us-gaap_ProceedsFromIssuanceOfCommonStock us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 4000000 4 false false 2 false true 43000000 43 false false 3 false true 397000000 397 false false 4 false true 927000000 927 false false No definition available. No authoritative reference available. false 48 5 us-gaap_ProceedsFromIssuanceOfLongTermDebt us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 13590000000 13590 false false 2 false true 43960000000 43960 false false 3 false true 42331000000 42331 false false 4 false true 74540000000 74540 false false No definition available. No authoritative reference available. false 49 5 us-gaap_ProceedsFromIssuanceOfSubordinatedLongTermDebt 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 0 0 false false 3 false true 5579000000 5579 false false 4 false true 0 0 false false No definition available. No authoritative reference available. false 50 4 ms_NetPaymentsForFinancingActivitiesAbstract ms false na duration string Net Payments for: [Abstract] 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 4 false false 0 0 false false Net Payments for: [Abstract] false 51 5 us-gaap_RepaymentsOfLongTermDebt us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true -5694000000 -5694 false false 2 false true -33175000000 -33175 false false 3 false true -56120000000 -56120 false false 4 false true -33120000000 -33120 false false No definition available. No authoritative reference available. false 52 5 us-gaap_PaymentsForRepurchaseOfPreferredStockAndPreferenceStock 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 -10950000000 -10950 false false 3 false true 0 0 false false 4 false true 0 0 false false No definition available. No authoritative reference available. false 53 5 ms_PaymentForRedemptionOfCommonStock ms false credit duration monetary Cash paid to redeem originally issued shares of Class B common stock in conjunction with the IPO. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false true 0 0 false false 4 false true -66000000 -66 false false Cash paid to redeem originally issued shares of Class B common stock in conjunction with the IPO. No authoritative reference available. false 54 5 us-gaap_PaymentsForRepurchaseOfOtherEquity 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 0 0 false false 3 false true -711000000 -711 false false 4 false true -3753000000 -3753 false false No definition available. No authoritative reference available. false 55 5 us-gaap_PaymentsForRepurchaseOfCommonStock us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true -3000000 -3 false false 2 false true -50000000 -50 false false 3 false true -1117000000 -1117 false false 4 false true -438000000 -438 false false No definition available. No authoritative reference available. false 56 5 ms_DividendsPaidToParentPursuantToSpinOff ms false credit duration monetary The cash outflow from the entity's earnings to the parent company pursuant to spin-off. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false true 0 0 false false 4 false true -5615000000 -5615 false false The cash outflow from the entity's earnings to the parent company pursuant to spin-off. No authoritative reference available. false 57 5 us-gaap_PaymentsOfDividends 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 -1732000000 -1732 false false 3 false true -1227000000 -1227 false false 4 false true -1219000000 -1219 false false No definition available. No authoritative reference available. false 58 4 us-gaap_NetCashProvidedByUsedInFinancingActivities us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 12774000000 12774 false false 2 false true 3024000000 3024 false false 3 false true -16984000000 -16984 false false 4 false true 38085000000 38085 false false No definition available. No authoritative reference available. true 59 3 us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 1514000000 1514 false false 2 false true 720000000 720 false false 3 false true -2546000000 -2546 false false 4 false true 594000000 594 false false No definition available. No authoritative reference available. false 60 3 us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease us-gaap true na duration monetary No definition available. false false false false false false false false false 1 false true 16000000 16 false false 2 false true -46679000000 -46679 false false 3 false true 53056000000 53056 false false 4 false true 4992000000 4992 false false No definition available. No authoritative reference available. true 61 3 us-gaap_CashAndCashEquivalentsAtCarryingValue us-gaap true debit instant monetary No definition available. false false false false false false true false false 1 false true 78654000000 78654 false false 2 false false 78670000000 78670 false false 3 false true 25598000000 25598 false false 4 false true 20606000000 20606 false false No definition available. No authoritative reference available. false 62 3 us-gaap_CashAndCashEquivalentsAtCarryingValue us-gaap true debit instant monetary No definition available. false false false false false false false true false 1 false true 78670000000 78670 false false 2 false true 31991000000 31991 false false 3 false true 78654000000 78654 false false 4 false true 25598000000 25598 false false No definition available. No authoritative reference available. false 63 3 us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract 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 4 false false 0 0 false false No definition available. false 64 4 us-gaap_CashAndDueFromBanks us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 13354000000 13354 false false 2 false true 6988000000 6988 false false 3 false true 11276000000 11276 false false 4 false true 7248000000 7248 false false No definition available. No authoritative reference available. false 65 4 us-gaap_InterestBearingDepositsInBanks us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 65316000000 65316 false false 2 false true 25003000000 25003 false false 3 false true 67378000000 67378 false false 4 false true 18350000000 18350 false false No definition available. No authoritative reference available. false 66 4 us-gaap_CashAndCashEquivalentsAtCarryingValue us-gaap true debit instant monetary No definition available. false false false false false false false true false 1 true true 78670000000 78670 false false 2 true true 31991000000 31991 false false 3 true true 78654000000 78654 false false 4 true true 25598000000 25598 false false No definition available. No authoritative reference available. false false 4 60 false Millions UnKnown UnKnown false true