State Street (STT) 10-Q 9 May 14 2014 Q1 Quarterly report Financial data

Document_And_Entity_Informatio

Document And Entity Information	3 Months Ended
	Mar. 31, 2014	Apr. 30, 2014
Document And Entity Information [Abstract]	'	'
Entity Registrant Name	'STATE STREET Corp	'
Entity Central Index Key	'0000093751	'
Current Fiscal Year End Date	'--03-31	'
Entity Filer Category	'Large Accelerated Filer	'
Document Type	'10-Q	'
Document Period End Date	31-Mar-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q1	'
Amendment Flag	'false	'
Entity Common Stock, Shares Outstanding	'	430,421,570

Consolidated_Statement_of_Inco

Consolidated Statement of Income (USD $)	3 Months Ended
In Millions, except Share data in Thousands, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013
Fee revenue:	'		'
Servicing fees	$1,238		$1,175
Management fees	292		263
Trading services	239		281
Securities finance	85		78
Processing fees and other	70		60
Total fee revenue	1,924		1,857
Net interest revenue:	'		'
Interest revenue	655		687
Interest expense	100		111
Net interest revenue	555		576
Gains (losses) related to investment securities, net:	'		'
Net gains (losses) from sales of available-for-sale securities	15		5
Losses from other-than-temporary impairment	-1		0
Losses reclassified (from) to other comprehensive income	-8		-3
Gains (losses) related to investment securities, net	6		2
Total revenue	2,485		2,435
Provision for loan losses	2		0
Expenses:	'		'
Compensation and employee benefits	1,157		1,035
Information systems and communications	244		237
Transaction processing services	191		180
Occupancy	114		116
Acquisition and restructuring costs	33		14
Professional services	105		79
Amortization of other intangible assets	54		53
Other	130		112
Total expenses	2,028		1,826
Income before income tax expense	455		609
Income tax expense	92		145
Net income	363		464
Net income available to common shareholders	$356		$455
Earnings per common share:	'		'
Basic (in dollars per share)	$0.83		$1
Diluted (in dollars per share)	$0.81	[1]	$0.98	[1]
Average common shares outstanding	'		'
Basic (in shares)	430,621		454,315
Diluted (in shares)	438,815		462,751
Cash dividends declared (in dollars per share)	$0.26		$0.26
[1]	Calculations reflect allocation of earnings to participating securities using the two-class method, as this computation is more dilutive than the treasury stock method.

Consolidated_Statement_of_Comp

Consolidated Statement of Comprehensive Income (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Statement of Comprehensive Income [Abstract]	'	'
Net income	$363	$464
Other comprehensive income (loss), net of related taxes:	'	'
Foreign currency translation, net of related taxes of $8 and ($64), respectively	27	-248
Change in net unrealized gains on available-for-sale securities, net of reclassification adjustment and net of related taxes of $162 and $29, respectively	259	51
Change in net unrealized gains (losses) on available-for-sale securities designated in fair value hedges, net of related taxes of ($6) and $9, respectively	-10	15
Other-than-temporary impairment on held-to-maturity securities related to factors other than credit, net of related taxes of $5 and $4, respectively	8	6
Change in net unrealized losses on cash flow hedges, net of related taxes of ($5) and $41, respectively	-7	64
Change in net unrealized losses on retirement plans, net of related taxes of $3 and $2, respectively	6	3
Other comprehensive income (loss)	283	-109
Total comprehensive income	$646	$355

Consolidated_Statement_of_Comp1

Consolidated Statement of Comprehensive Income (Unaudited) (Parenthetical) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Statement of Comprehensive Income [Abstract]	'	'
Foreign currency translation, net of related taxes of	$8	($64)
Change in net unrealized losses on available-for-sale securities, net of reclassification adjustment and net of related taxes of	162	29
Change in net unrealized losses on available-for-sale securities designated in fair value hedges, net of related taxes of	-6	9
Other-than-temporary impairment on held-to-maturity securities related to factors other than credit, net of related taxes of	5	4
Change in net unrealized losses on cash flow hedges, net of related taxes of	-5	41
Change in minimum pension liability, net of related taxes of	$3	$2

Consolidated_Statement_of_Cond

Consolidated Statement of Condition (USD $)	Mar. 31, 2014	Dec. 31, 2013
Assets:	'	'
Cash and due from banks	$3,877,000,000	$3,220,000,000
Interest-bearing deposits with banks	75,796,000,000	64,257,000,000
Securities purchased under resale agreements	6,087,000,000	6,230,000,000
Trading account assets	889,000,000	843,000,000
Investment securities available for sale	99,162,000,000	99,174,000,000
Investment securities held to maturity (fair value of $18,326 and $17,560)	18,342,000,000	17,740,000,000
Loans and leases (less allowance for losses of $30 and $28)	16,084,000,000	13,458,000,000
Premises and equipment (net of accumulated depreciation of $4,521 and $4,417)	1,896,000,000	1,860,000,000
Accrued interest and fees receivable	2,197,000,000	2,123,000,000
Goodwill	6,038,000,000	6,036,000,000
Other intangible assets	2,306,000,000	2,360,000,000
Other assets	23,989,000,000	25,990,000,000
Total assets	256,663,000,000	243,291,000,000
Deposits:	'	'
Noninterest-bearing	72,800,000,000	65,614,000,000
Interest-bearing—U.S.	15,327,000,000	13,392,000,000
Interest-bearing—non-U.S.	106,521,000,000	103,262,000,000
Total deposits	194,648,000,000	182,268,000,000
Securities sold under repurchase agreements	8,953,000,000	7,953,000,000
Federal funds purchased	18,000,000	19,000,000
Other short-term borrowings	3,811,000,000	3,780,000,000
Accrued expenses and other liabilities	18,457,000,000	19,194,000,000
Long-term debt	9,503,000,000	9,699,000,000
Total liabilities	235,390,000,000	222,913,000,000
Commitments, guarantees and contingencies (notes 7 and 8)	'	'
Shareholders’ equity:	'	'
Common stock, $1 par: 750,000,000 shares authorized; 503,881,095 and 503,882,841 shares issued	504,000,000	504,000,000
Surplus	9,737,000,000	9,776,000,000
Retained earnings	13,639,000,000	13,395,000,000
Accumulated other comprehensive income (loss)	188,000,000	-95,000,000
Treasury stock, at cost (73,440,407 and 69,754,255 shares)	-4,028,000,000	-3,693,000,000
Total shareholders’ equity	21,273,000,000	20,378,000,000
Total liabilities and shareholders’ equity	256,663,000,000	243,291,000,000
Series C Preferred Stock	'	'
Shareholders’ equity:	'	'
Preferred stock, no par: 3,500,000 shares authorized; Series C, 5,000 shares issued and outstanding and Series D, 7,500 shares issued and outstanding	491,000,000	491,000,000
Series D Preferred Stock	'	'
Shareholders’ equity:	'	'
Preferred stock, no par: 3,500,000 shares authorized; Series C, 5,000 shares issued and outstanding and Series D, 7,500 shares issued and outstanding	$742,000,000	$0

Consolidated_Statement_of_Cond1

Consolidated Statement of Condition (Parenthetical) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, except Share data, unless otherwise specified
Current Assets:	'	'
Investment securities held to maturity, fair value	$18,326	$17,560
Loans and leases, allowance for losses	30	28
Premises and equipment, accumulated depreciation	$4,521	$4,417
Stockholders' Equity:	'	'
Common stock, par value (in dollars per share)	$1	$1
Common stock, shares authorized (in shares)	750,000,000	750,000,000
Common stock, shares issued (in shares)	503,881,095	503,882,841
Preferred stock, shares authorized (in shares)	3,500,000	3,500,000
Treasury stock, shares (in shares)	73,440,407	69,754,255
Series C Preferred Stock	'	'
Stockholders' Equity:	'	'
Preferred stock, shares issued, Series C (in shares)	5,000	5,000
Preferred stock, shares outstanding, Series C (in shares)	5,000	5,000
Series D Preferred Stock	'	'
Stockholders' Equity:	'	'
Preferred stock, shares issued, Series C (in shares)	7,500	'
Preferred stock, shares outstanding, Series C (in shares)	7,500	'

Consolidated_Statement_of_Chan

Consolidated Statement of Changes In Shareholders' Equity (USD $)	Total	PREFERRED STOCK	COMMON STOCK	Surplus	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	TREASURY STOCK
In Millions, except Share data, unless otherwise specified
Beginning balance at Dec. 31, 2012	$20,869	$489	$504	$9,667	$11,751	$360	($1,902)
Beginning balance (shares) at Dec. 31, 2012	'	'	503,900,000	'	'	'	45,238,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'	'
Net income	464	'	'	'	464	'	'
Other comprehensive income (loss)	-109	'	'	'	'	-109	'
Cash dividends declared:	'	'	'	'	'	'	'
Common stock	-118	'	'	'	-118	'	'
Preferred stock	-7	'	'	'	-7	'	'
Common stock acquired	-360	'	'	'	'	'	-360
Common stock acquired (shares)	'	'	'	'	'	'	6,548,000
Common stock awards and options exercised, including related taxes	130	'	'	2	'	'	128
Common stock awards and options exercised, including related taxes (shares)	'	'	-4,000	'	'	'	-3,475,000
Other	0	'	'	'	'	'	'
Other (shares)	'	'	'	'	'	'	-7,000
Ending balance at Mar. 31, 2013	20,869	489	504	9,669	12,090	251	-2,134
Ending balance (shares) at Mar. 31, 2013	'	'	503,896,000	'	'	'	48,304,000
Beginning balance at Dec. 31, 2013	20,378	491	504	9,776	13,395	-95	-3,693
Beginning balance (shares) at Dec. 31, 2013	'	'	503,883,000	'	'	'	69,754,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'	'
Net income	363	'	'	'	363	'	'
Other comprehensive income (loss)	283	'	'	'	'	283	'
Preferred stock issued	742	742	'	'	'	'	'
Cash dividends declared:	'	'	'	'	'	'	'
Common stock	-112	'	'	'	-112	'	'
Preferred stock	-6	'	'	'	-6	'	'
Common stock acquired	-420	'	'	'	'	'	-420
Common stock acquired (shares)	'	'	'	'	'	'	6,075,000
Common stock awards and options exercised, including related taxes	46	'	'	-39	'	'	85
Common stock awards and options exercised, including related taxes (shares)	'	'	-2,000	'	'	'	-2,403,000
Other	-1	'	'	'	-1	'	'
Other (shares)	'	'	'	'	'	'	14,000
Ending balance at Mar. 31, 2014	$21,273	$1,233	$504	$9,737	$13,639	$188	($4,028)
Ending balance (shares) at Mar. 31, 2014	'	'	503,881,000	'	'	'	73,440,000

Consolidated_Statement_of_Chan1

Consolidated Statement of Changes In Shareholders' Equity (Unaudited) (Parenthetical) (USD $)	3 Months Ended
In Millions, except Per Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Statement of Stockholders' Equity [Abstract]	'	'
Cash dividends declared (in dollars per share)	$0.26	$0.26
Common stock awards and options exercised, related taxes	$41	$27

Consolidated_Statement_of_Cash

Consolidated Statement of Cash Flows (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Operating Activities:	'	'
Net income	$363	$464
Adjustments to reconcile net income to net cash (used in) provided by operating activities:	'	'
Deferred income tax expense	7	57
Amortization of other intangible assets	54	53
Other non-cash adjustments for depreciation, amortization and accretion, net	99	107
Gains related to investment securities, net	-6	-2
Change in trading account assets, net	-46	-17
Change in accrued interest and fees receivable, net	-74	-133
Change in collateral deposits, net	-419	-321
Change in unrealized losses on foreign exchange derivatives, net	267	72
Change in other assets, net	34	639
Change in accrued expenses and other liabilities, net	1,542	-734
Other, net	126	197
Net cash provided by operating activities	1,947	382
Investing Activities:	'	'
Net (increase) decrease in interest-bearing deposits with banks	-11,539	11,539
Net decrease (increase) in securities purchased under resale agreements	143	-3,687
Proceeds from sales of available-for-sale securities	1,816	2,750
Proceeds from maturities of available-for-sale securities	8,733	9,723
Purchases of available-for-sale securities	-10,377	-8,240
Proceeds from maturities of available-for-sale securities	667	437
Proceeds from sales of held-to-maturity securities	2	0
Purchases of held-to-maturity securities	-1,157	-2,570
Net increase in loans	-2,628	-1,702
Purchases of equity investments and other long-term assets	-82	-51
Purchases of premises and equipment	-110	-119
Other, net	18	36
Net cash (used in) provided by investing activities	-14,514	8,116
Financing Activities:	'	'
Net decrease in time deposits	-1,084	-10,218
Net increase in all other deposits	13,464	812
Net increase in short-term borrowings	1,030	3,555
Payments for long-term debt and obligations under capital leases	-257	-7
Proceeds from issuance of preferred stock	742	0
Proceeds from exercises of common stock options	9	60
Purchases of common stock	-420	-360
Repurchases of common stock for employee tax withholding	-140	-112
Payments for cash dividends	-120	-110
Net cash provided by (used in) financing activities	13,224	-6,380
Net increase	657	2,118
Cash and due from banks at beginning of period	3,220	2,590
Cash and due from banks at end of period	$3,877	$4,708

Basis_of_Presentation

Basis of Presentation	3 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
Basis of Presentation	'
	Basis of Presentation
	The accounting and financial reporting policies of State Street Corporation conform to U.S. generally accepted accounting principles, referred to as GAAP. State Street Corporation, the parent company, is a financial holding company headquartered in Boston, Massachusetts. Unless otherwise indicated or unless the context requires otherwise, all references in these notes to consolidated financial statements to “State Street,” “we,” “us,” “our” or similar references mean State Street Corporation and its subsidiaries on a consolidated basis. Our principal banking subsidiary is State Street Bank and Trust Company, or State Street Bank.
	We have two lines of business:
	Investment Servicing provides services for mutual funds, collective investment funds and other investment pools, corporate and public retirement plans, insurance companies, foundations and endowments worldwide. Products include custody; product- and participant-level accounting; daily pricing and administration; master trust and master custody; record-keeping; cash management; foreign exchange, brokerage and other trading services; securities finance; deposit and short-term investment facilities; loans and lease financing; investment manager and alternative investment manager operations outsourcing; and performance, risk and compliance analytics to support institutional investors.
	Investment Management, through State Street Global Advisors, or SSgA, provides a broad array of investment management, investment research and investment advisory services to corporations, public funds and other sophisticated investors. SSgA offers active and passive asset management strategies across equity, fixed-income and cash asset classes. Products are distributed directly and through intermediaries using a variety of investment vehicles, including exchange-traded funds, or ETFs, such as the SPDR® ETF brand.
	The consolidated financial statements accompanying these condensed notes are unaudited. In the opinion of management, all adjustments, consisting only of normal recurring adjustments, which are necessary for a fair statement of the consolidated results of operations in these financial statements, have been made. Certain previously reported amounts presented in this Form 10-Q have been reclassified to conform to current-period presentation. Events occurring subsequent to the date of our consolidated statement of condition were evaluated for potential recognition or disclosure in our
	consolidated financial statements through the date we filed this Form 10-Q with the SEC.
	The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions in the application of certain of our significant accounting policies that may materially affect the reported amounts of assets, liabilities, equity, revenue, and expenses. As a result of unanticipated events or circumstances, actual results could differ from those estimates. Amounts dependent on subjective or complex judgments in the application of accounting policies considered by management to be relatively more significant in this regard are those associated with our accounting for recurring fair-value measurements; other-than-temporary impairment of investment securities; and impairment of goodwill and other intangible assets. Among other effects, unanticipated events or circumstances could result in future impairment of investment securities, goodwill or other intangible assets.
	Our consolidated statement of condition as of December 31, 2013 included in the accompanying consolidated financial statements was derived from the audited financial statements as of that date, but does not include all notes required by GAAP for a complete set of consolidated financial statements. The accompanying consolidated financial statements and these condensed notes should be read in conjunction with the financial and risk factors information included in our 2013 Annual Report on Form 10-K, which we previously filed with the SEC.
	Recent Accounting Developments:
	In April 2014, the FASB issued an amendment to GAAP that revises the criteria for the treatment and disclosure of discontinued operations. The amendment allows entities to have significant continuing involvement and continuing cash flows with the discontinued operation, but requires additional disclosure for discontinued operations and disclosure for disposals deemed to be material that do not meet the definition of a discontinued operation. The presentation and disclosure requirements are effective, for State Street, beginning on January 1, 2015, and are required to be applied prospectively to discontinued operations occurring after that date.
	In January 2014, the FASB issued an amendment to GAAP that allows an investor in an affordable housing project, if the project meets certain defined conditions, to amortize the cost of their investment in proportion to the tax credits and other tax benefits they receive, and reflect it as part of income tax expense rather than as revenue from operations. The amendment is effective, for State Street, for interim and annual periods beginning after December 15, 2014, with early adoption permitted, and must be applied retrospectively. At this time, we have not chosen to early-adopt the amendment. Our adoption of the amendment is not expected to have a material effect on our consolidated financial statements.

Fair_Value

Fair Value	3 Months Ended
	Mar. 31, 2014
Fair Value Disclosures [Abstract]	'
Fair Value	'
	Fair Value
	Fair-Value Measurements:
	We carry trading account assets, investment securities available for sale and various types of derivative financial instruments at fair value in our consolidated statement of condition on a recurring basis. Changes in the fair values of these financial assets and liabilities are recorded either as components of our consolidated statement of income or as components of accumulated other comprehensive income, or AOCI, within shareholders' equity in our consolidated statement of condition.
	We measure fair value for the above-described financial assets and liabilities in conformity with GAAP that governs the measurement of the fair value of financial instruments. Management believes that its valuation techniques and underlying assumptions used to measure fair value conform to the provisions of GAAP. We categorize the financial assets and liabilities that we carry at fair value based on a prescribed three-level valuation hierarchy. The hierarchy gives the highest priority to quoted prices in active markets for identical assets or liabilities (level 1) and the lowest priority to valuation methods using significant unobservable inputs (level 3). If the inputs used to measure a financial asset or liability cross different levels of the hierarchy, categorization is based on the lowest-level input that is most significant to the fair-value measurement. Management's assessment of the significance of a particular input to the overall fair-value measurement of a financial asset or liability requires judgment, and considers factors specific to that asset or liability. The three valuation levels are described below.
	Level 1. Financial assets and liabilities with values based on unadjusted quoted prices for identical assets or liabilities in an active market. Fair value is measured using unadjusted quoted prices in active markets for identical securities. Our level-1 financial assets and liabilities primarily include positions in U.S. government securities and highly liquid U.S. and non-U.S. government fixed-income securities. We may carry U.S. government securities in our available-for-sale portfolio in connection with our asset-and-liability management activities. Our level-1 financial assets also include active exchange-traded equity securities.
	Level 2. Financial assets and liabilities with values based on quoted prices for similar assets and liabilities in active markets, and inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the asset or liability. Level-2 inputs include the following:
	•	Quoted prices for similar assets or liabilities in active markets;
	•	Quoted prices for identical or similar assets or liabilities in non-active markets;
	•	Pricing models whose inputs are observable for substantially the full term of the asset or liability; and
	•	Pricing models whose inputs are derived principally from, or corroborated by, observable market information through correlation or other means for substantially the full term of the asset or liability.
	Our level-2 financial assets and liabilities primarily include trading account assets and fixed-income investment securities available for sale, as well as various types of foreign exchange and interest-rate derivative instruments.
	Fair value for our investment securities available for sale categorized in level 2 is measured primarily using information obtained from independent third parties. This third-party information is subject to review by management as part of a validation process, which includes obtaining an understanding of the underlying assumptions and the level of market participant information used to support those assumptions. In addition, management compares significant assumptions used by third parties to available market information. Such information may include known trades or, to the extent that trading activity is limited, comparisons to market research information pertaining to credit expectations, execution prices and the timing of cash flows, and where information is available, back-testing.
	Derivative instruments categorized in level 2 predominantly represent foreign exchange contracts used in our trading activities, for which fair value is measured using discounted cash-flow techniques, with inputs consisting of observable spot and forward points, as well as observable interest-rate curves. With respect to derivative instruments, we evaluate the impact on valuation of the credit risk of our counterparties and our own credit risk. We consider factors such as the likelihood of default by us and our counterparties, our current and potential future net exposures and remaining maturities in determining the fair value. Valuation adjustments associated with derivative instruments were not material to those instruments in the three months ended March 31, 2014 or 2013.
	Level 3. Financial assets and liabilities with values based on prices or valuation techniques that require inputs that are both unobservable in the market and significant to the overall measurement of fair value. These inputs reflect management's judgment about the assumptions that a market participant would use in pricing the financial asset or liability, and are based on the best available information, some of which is internally developed. The following provides a more detailed discussion of our financial assets and liabilities that we may categorize in level 3 and the related valuation methodology.
	•	The fair value of our investment securities categorized in level 3 is measured using information obtained from third-party sources, typically non-binding broker or dealer quotes, or through the use of internally-developed pricing models. Management has evaluated its methodologies used to measure fair value, but has considered the level of observable market information to be insufficient to categorize the securities in level 2.
	•	The fair value of foreign exchange contracts, primarily options, is measured using an option-pricing model. Because of a limited number of observable transactions, certain model inputs are not observable, such as implied volatility surface, but are derived from observable market information.
	•	The fair value of certain interest-rate caps with long-dated maturities, is measured using a matrix-pricing approach. Observable market prices are not available for these derivatives, so extrapolation is necessary to value these instruments, since they have a strike and/or maturity outside of the matrix.
	Our level-3 financial assets and liabilities are similar in structure and profile to our level-1 and level-2 financial instruments, but they trade in less-liquid markets, and the measurement of their fair value is inherently more difficult. As of March 31, 2014, on a gross basis, we categorized in level 3 approximately 6% of our financial assets carried at fair value on a recurring basis. As of the same date and on the same basis, the percentage of our financial liabilities categorized in level 3 to our financial liabilities carried at fair value on a recurring basis was not significant. The fair value of investment securities categorized in level 3 that was measured using non-binding quotes and internally-developed pricing-model inputs composed approximately 98% and 2%, respectively, of the total fair value of the investment securities categorized in level 3 as of both March 31, 2014 and December 31, 2013.
	The process used to measure the fair value of our level-3 financial assets and liabilities is overseen by a valuation group within Corporate Finance, separate from the business units that manage the assets and liabilities. This function, which develops and manages the valuation process, reports to State Street's Valuation Committee. The Valuation Committee, composed of senior management from separate business units, Enterprise Risk Management, a corporate risk oversight group, and Corporate Finance, oversees adherence to State Street's valuation policies.
	The valuation group performs validation of the pricing information obtained from third-party sources in order to evaluate reasonableness and consistency with market experience in similar asset classes. Monthly analyses include a review of price changes relative to overall trends, credit analysis and other relevant procedures (discussed below). In addition, prices for level-3 securities carried in our investment portfolio are tested on a sample basis based on unexpected pricing movements. These sample prices are then corroborated through price recalculations, when applicable, using available market information, which is obtained separately from the third-party pricing source. The recalculated prices are compared to market-research information pertaining to credit expectations, execution prices and the timing of cash flows, and where information is available, back-testing. If a difference is identified and it is determined that there is a significant impact requiring an adjustment, the adjustment is presented to the Valuation Committee for review and consideration.
	Validation is also performed on fair-value measurements determined using internally-developed pricing models. The pricing models are subject to validation through our Model Assessment Committee, a corporate risk oversight committee that provides technical support and input to the Valuation Committee. This validation process incorporates a review of a diverse set of model and trade parameters across a broad range of values in order to evaluate the model's suitability for valuation of a particular financial instrument type, as well as the model's accuracy in reflecting the characteristics of the related financial asset or liability and its significant risks. Inputs and assumptions, including any price-valuation adjustments, are developed by the business units and separately reviewed by the valuation group. Model valuations are compared to available market information including appropriate proxy instruments and other benchmarks to highlight abnormalities for further investigation.
	Measuring fair value requires the exercise of management judgment. The level of subjectivity and the degree of management judgment required is more significant for financial instruments whose fair value is measured using inputs that are not observable. The areas requiring significant judgment are identified, documented and reported to the Valuation Committee as part of the valuation control framework. We believe that our valuation methods are appropriate; however, the use of different methodologies or assumptions, particularly as they apply to level-3 financial assets and liabilities, could materially affect our fair-value measurements as of the reporting date.
	The following tables present information with respect to our financial assets and liabilities carried at fair value in our consolidated statement of condition on a recurring basis as of the dates indicated. No transfers of financial assets or liabilities between levels 1 and 2 occurred during the three months ended March 31, 2014 or the year ended December 31, 2013.
		Fair-Value Measurements on a Recurring Basis
		as of March 31, 2014
	(In millions)	Quoted Market			Pricing Methods			Pricing Methods				Impact of Netting(1)			Total Net
		Prices in Active			with Significant			with Significant							Carrying Value
		Markets			Observable			Unobservable							in Consolidated
		(Level 1)			Market Inputs			Market Inputs							Statement of
					(Level 2)			(Level 3)							Condition
	Assets:
	Trading account assets:
	U.S. government securities	$	20		$	—		$	—						$	20
	Non-U.S. government securities	401			—			—							401
	Other	60			408			—							468
	Total trading account assets	481			408			—							889
	Investment securities available for sale:
	U.S. Treasury and federal agencies:
	Direct obligations	1,280			683			—							1,963
	Mortgage-backed securities	—			22,992			100							23,092
	Asset-backed securities:
	Student loans	—			13,947			333							14,280
	Credit cards	—			7,237			—							7,237
	Sub-prime	—			1,155			—							1,155
	Other	—			576			4,304							4,880
	Total asset-backed securities	—			22,915			4,637							27,552
	Non-U.S. debt securities:
	Mortgage-backed securities	—			11,196			—							11,196
	Asset-backed securities	—			4,382			612							4,994
	Government securities	—			3,692			—							3,692
	Other	—			4,522			462							4,984
	Total non-U.S. debt securities	—			23,792			1,074							24,866
	State and political subdivisions	—			10,402			42							10,444
	Collateralized mortgage obligations	—			5,060			202							5,262
	Other U.S. debt securities	—			4,938			8							4,946
	U.S. equity securities	—			36			—							36
	Non-U.S. equity securities	—			1			—							1
	U.S. money-market mutual funds	—			993			—							993
	Non-U.S. money-market mutual funds	—			7			—							7
	Total investment securities available for sale	1,280			91,819			6,063							99,162
	Other assets:
	Derivative instruments:
	Foreign exchange contracts	—			8,312			6				$	(4,850	)	3,468
Interest-rate contracts	—			56			—				(56		)	—
Other derivative contracts	—			2			—				(1		)	1
Total derivative instruments	—			8,370			6				(4,907		)	3,469
Other	100			—			—				—			100
Total assets carried at fair value	$	1,861		$	100,597		$	6,069			$	(4,907	)	$	103,620
Liabilities:
Accrued expenses and other liabilities:
Derivative instruments:
Foreign exchange contracts	$	—		$	7,834		$	8			$	(3,752	)	$	4,090
Interest-rate contracts	—			269			—				(56		)	213
Other derivative contracts	—			1			9				(1		)	9
Total derivative instruments	—			8,104			17				(3,809		)	4,312
Other	100			—			—				—			100
Total liabilities carried at fair value	$	100		$	8,104		$	17			$	(3,809	)	$	4,412
(1) Represents counterparty netting against level-2 financial assets and liabilities, where a legally enforceable master netting agreement exists between State Street and the counterparty. Netting also reflects asset and liability reductions of $1.37 billion and $274 million, respectively, for cash collateral received from and provided to derivative counterparties.
	Fair-Value Measurements on a Recurring Basis
	as of December 31, 2013
(In millions)	Quoted Market			Pricing Methods			Pricing Methods				Impact of Netting(1)			Total Net
	Prices in Active			with Significant			with Significant							Carrying Value
	Markets			Observable			Unobservable							in Consolidated
	(Level 1)			Market Inputs			Market Inputs							Statement of
				(Level 2)			(Level 3)							Condition
Assets:
Trading account assets:
U.S. government securities	$	20		$	—		$	—						$	20
Non-U.S. government securities	399			—			—							399
Other	67			357			—							424
Total trading account assets	486			357			—							843
Investment securities available for sale:
U.S. Treasury and federal agencies:
Direct obligations	—			709			—							709
Mortgage-backed securities	—			22,847			716							23,563
Asset-backed securities:
Student loans	—			14,119			423							14,542
Credit cards	—			8,186			24							8,210
Sub-prime	—			1,203			—							1,203
Other	—			532			4,532							5,064
Total asset-backed securities	—			24,040			4,979							29,019
Non-U.S. debt securities:
Mortgage-backed securities	—			10,654			375							11,029
Asset-backed securities	—			4,592			798							5,390
Government securities	—			3,761			—							3,761
Other	—			4,263			464							4,727
Total non-U.S. debt securities	—			23,270			1,637							24,907
State and political subdivisions	—			10,220			43							10,263
Collateralized mortgage obligations	—			5,107			162							5,269
Other U.S. debt securities	—			4,972			8							4,980
U.S. equity securities	—			34			—							34
Non-U.S. equity securities	—			1			—							1
U.S. money-market mutual funds	—			422			—							422
Non-U.S. money-market mutual funds	—			7			—							7
Total investment securities available for sale	—			91,629			7,545							99,174
Other assets:
Derivatives instruments:
Foreign exchange contracts	—			11,892			19				$	(6,442	)	5,469
Interest-rate contracts	—			65			—				(59		)	6
Other derivative contracts	—			1			—				—			1
Total derivative instruments	—			11,958			19				(6,501		)	5,476
Other	97			—			—				—			97
Total assets carried at fair value	$	583		$	103,944		$	7,564			$	(6,501	)	$	105,590
Liabilities:
Accrued expenses and other liabilities:
Derivative instruments:
Foreign exchange contracts	$	—		$	11,454		$	17			$	(5,458	)	$	6,013
Interest-rate contracts	—			331			—				(94		)	237
Other derivative contracts	—			—			9				—			9
Total derivative instruments	—			11,785			26				(5,552		)	6,259
Other	97			—			—				—			97
Total liabilities carried at fair value	$	97		$	11,785		$	26			$	(5,552	)	$	6,356
(1) Represents counterparty netting against level-2 financial assets and liabilities, where a legally enforceable master netting agreement exists between State Street and the counterparty. Netting also reflects asset and liability reductions of $1.93 billion and $979 million, respectively, for cash collateral received from and provided to derivative counterparties.
The following tables present activity related to our level-3 financial assets and liabilities during the three months ended March 31, 2014 and 2013, respectively. Transfers into and out of level 3 are reported as of the beginning of the period. During the three months ended March 31, 2014 and 2013, transfers out of level 3 were mainly related to certain mortgage- and asset-backed securities, including non-U.S. debt securities, for which fair value was measured using prices for which observable market information became available.
	Fair-Value Measurements Using Significant Unobservable Inputs
	Three Months Ended March 31, 2014
	Fair			Total Realized and							Purchases			Issuances			Sales			Settlements			Transfers		Transfers			Fair		Change in
	Value as of			Unrealized Gains (Losses)																			into		out of			Value as of		Unrealized
	December 31,																						Level 3		Level 3			March 31,		Gains
	2013																											2014		(Losses)
																														Related to
																														Financial
																														Instruments
																														Held as of
																														March 31,
(In millions)				Recorded			Recorded																							2014
				in			in Other
				Revenue			Comprehensive
							Income
Assets:
Investment securities available for sale:
U.S. Treasury and federal agencies, mortgage-backed securities	$	716		$	—		$	—			$	—		$	—		$	—		$	(5	)	$	—	$	(611	)	$	100
Asset-backed securities:
Student loans	423			1			1				—			—			—			(13		)	—		(79		)	333
Credit cards	24			—			—				—			—			—			(24		)	—		—			—
Other	4,532			15			(4		)		6			—			—			(245		)	—		—			4,304
Total asset-backed securities	4,979			16			(3		)		6			—			—			(282		)	—		(79		)	4,637
Non-U.S. debt securities:
Mortgage-backed securities	375			—			—				—			—			—			—			—		(375		)	—
Asset-backed securities	798			2			(1		)		—			—			—			(63		)	—		(124		)	612
Other	464			—			(1		)		—			—			(1		)	—			—		—			462
Total non-U.S. debt securities	1,637			2			(2		)		—			—			(1		)	(63		)	—		(499		)	1,074
State and political subdivisions	43			—			—				—			—			—			(1		)	—		—			42
Collateralized mortgage obligations	162			—			—				80			—			(6		)	(6		)	—		(28		)	202
Other U.S. debt securities	8			—			—				—			—			—			—			—		—			8
Total investment securities available for sale	7,545			18			(5		)		86			—			(7		)	(357		)	—		(1,217		)	6,063
Other assets:
Derivative instruments:
Derivative instruments, Foreign exchange contracts	19			(11		)	—				7			—			—			(9		)	—		—			6		$	(7	)
Total derivative instruments	19			(11		)	—				7			—			—			(9		)	—		—			6		(7		)
Total assets carried at fair value	$	7,564		$	7		$	(5	)		$	93		$	—		$	(7	)	$	(366	)	$	—	$	(1,217	)	$	6,069	$	(7	)
	Fair-Value Measurements Using Significant Unobservable Inputs
	Three Months Ended March 31, 2014
	Fair			Total Realized and							Purchases			Issuances			Sales			Settlements			Transfers		Transfers			Fair		Change in
	Value as of			Unrealized (Gains) Losses																			into		out of			Value as of		Unrealized
	December 31,																						Level 3		Level 3			March 31,		(Gains)
	2013																											2014		Losses
																														Related to
																														Financial
																														Instruments
																														Held as of
																														March 31,
(In millions)				Recorded			Recorded																							2014
				in			in Other
				Revenue			Comprehensive
							Income
Liabilities:
Accrued expenses and other liabilities:
Derivative instruments:
Foreign exchange contracts	$	17		$	(10	)	$	—			$	—		$	7		$	—		$	(6	)	$	—	$	—		$	8	$	(5	)
Other	9			—			—				—			—			—			—			—		—			9		—
Total derivative instruments	26			(10		)	—				—			7			—			(6		)	—		—			17		(5		)
Total liabilities carried at fair value	$	26		$	(10	)	$	—			$	—		$	7		$	—		$	(6	)	$	—	$	—		$	17	$	(5	)
	Fair-Value Measurements Using Significant Unobservable Inputs
	Three Months Ended March 31, 2013
	Fair			Total Realized and							Purchases			Issuances			Sales			Settlements			Transfers		Transfers			Fair		Change in
	Value as of December 31,			Unrealized Gains (Losses)																			into		out of			Value as of		Unrealized
	2012																						Level 3		Level 3			March 31,		Gains
																												2013		(Losses)
																														Related to
																														Financial
																														Instruments
																														Held as of
																														31-Mar
(In millions)				Recorded			Recorded																							2013
				in			in Other
				Revenue			Comprehensive
							Income
Assets:
Investment securities available for sale:
U.S. Treasury and federal agencies:
Mortgage-backed securities	$	825		$	—		$	—			$	—		$	—		$	—		$	(27	)	$	—	$	—		$	798
Asset-backed securities:
Student loans	588			—			7				—			—			(26		)	(8		)	—		(100		)	461
Credit cards	67			—			—				—			—			—			(43		)	—		—			24
Other	3,994			13			21				180			—			(10		)	(326		)	—		—			3,872
Total asset-backed securities	4,649			13			28				180			—			(36		)	(377		)	—		(100		)	4,357
Non-U.S. debt securities:
Mortgage-backed securities	555			—			—				—			—			—			(17		)	—		(207		)	331
Asset-backed securities	524			2			3				51			—			—			(33		)	—		(77		)	470
Other	140			—			—				179			—			—			(3		)	—		(40		)	276
Total non-U.S. debt securities	1,219			2			3				230			—			—			(53		)	—		(324		)	1,077
State and political subdivisions	48			—			1				—			—			—			(2		)	—		—			47
Collateralized mortgage obligations	117			—			—				—			—			—			(9		)	—		—			108
Other U.S. debt securities	9			—			—				—			—			—			—			—		—			9
Total investment securities available for sale	6,867			15			32				410			—			(36		)	(468		)	—		(424		)	6,396
Other assets:
Derivative instruments:
Foreign exchange contracts	113			95			—				53			—			—			(89		)	—		—			172		$	53
Total derivative instruments	113			95			—				53			—			—			(89		)	—		—			172		53
Total assets carried at fair value	$	6,980		$	110		$	32			$	463		$	—		$	(36	)	$	(557	)	$	—	$	(424	)	$	6,568	$	53
	Fair-Value Measurements Using Significant Unobservable Inputs
	Three Months Ended March 31, 2013
	Fair			Total Realized and							Purchases			Issuances			Sales			Settlements			Transfers		Transfers			Fair		Change in
	Value as of December 31,			Unrealized (Gains) Losses																			into		out of			Value as of		Unrealized
	2012																						Level 3		Level 3			March 31,		(Gains)
																												2013		Losses
																														Related to
																														Financial
																														Instruments
																														Held as of
																														March 31,
(In millions)				Recorded			Recorded																							2013
				in			in Other
				Revenue			Comprehensive
							Income
Liabilities:
Accrued expenses and other liabilities:
Derivative instruments:
Foreign exchange contracts	$	106		$	61		$	—			$	—		$	50		$	—		$	(64	)	$	—	$	—		$	153	$	39
Other	9			—			—				—			—			—			—			—		—			9		—
Total derivative instruments	115			61			—				—			50			—			(64		)	—		—			162		39
Total liabilities carried at fair value	$	115		$	61		$	—			$	—		$	50		$	—		$	(64	)	$	—	$	—		$	162	$	39
The following table presents total realized and unrealized gains and losses for the periods indicated that were recorded in revenue for our level-3 financial assets and liabilities:
	Three Months Ended March 31,
	Total Realized and						Change in
	Unrealized Gains						Unrealized Gains
	(Losses) Recorded						(Losses) Related to
	in Revenue						Financial
							Instruments Held as of March 31,
(In millions)	2014			2013			2014				2013
Fee revenue:
Trading services	$	(1	)	$	34		$	(2	)		$	14
Total fee revenue	(1		)	34			(2		)		14
Net interest revenue	18			15			—				—
Total revenue	$	17		$	49		$	(2	)		$	14
The following table presents quantitative information, as of the dates indicated, about the valuation techniques and significant unobservable inputs used in the valuation of our level-3 financial assets and liabilities measured at fair value on a recurring basis for which we use internally-developed pricing models. The significant unobservable inputs for our level-3 financial assets and liabilities whose fair value is measured using pricing information from non-binding broker or dealer quotes are not included in the table, as the specific inputs applied are not provided by the broker/dealer.
		Quantitative Information about Level-3 Fair-Value Measurements
		Fair Value										Weighted-Average
(Dollars in millions)		As of March 31, 2014			As of December 31, 2013			Valuation Technique		Significant		As of March 31, 2014		As of December 31, 2013
										Unobservable Input
Significant unobservable inputs readily available to State Street:
Assets:
Asset-backed securities, student loans		$	14		$	13		Discounted cash flows		Credit spread		2.9	%	3.5	%
Asset-backed securities, credit cards		—			24			Discounted cash flows		Credit spread		—		2
Asset-backed securities, other		87			92			Discounted cash flows		Credit spread		1.3		1.5
State and political subdivisions		42			43			Discounted cash flows		Credit spread		1.7		1.7
Derivative instruments, foreign exchange contracts		6			19			Option model		Volatility		8		11.4
Total		$	149		$	191
Liabilities:
Derivative instruments, foreign exchange contracts		$	8		$	17		Option model		Volatility		8		11.2
Derivative instruments, other(1)		9			9			Discounted cash flows		Participant redemptions		7.4		7.5
Total		$	17		$	26
(1) Relates to stable value wrap contracts; refer to the sensitivity discussion following the tables presented below, and to note 7.
The following tables present information with respect to the composition of our level-3 financial assets and
liabilities, by availability of significant unobservable inputs, as of the dates indicated:
31-Mar-14		Significant Unobservable Inputs Readily Available to State Street(1)			Significant Unobservable Inputs Not Developed by State Street and Not Readily Available(2)			Total Assets and Liabilities with Significant Unobservable Inputs
(In millions)
Assets:
U.S. Treasury and federal agencies, mortgage-backed securities		$	—		$	100		$	100
Asset-backed securities, student loans		14			319			333
Asset-backed securities, other		87			4,217			4,304
Non-U.S. debt securities, asset-backed securities		—			612			612
Non-U.S. debt securities, other		—			462			462
State and political subdivisions		42			—			42
Collateralized mortgage obligations		—			202			202
Other U.S.debt securities		—			8			8
Derivative instruments, foreign exchange contracts		6			—			6
Total		$	149		$	5,920		$	6,069
Liabilities:
Derivative instruments, foreign exchange contracts		$	8		$	—		$	8
Derivative instruments, other		9			—			9
Total		$	17		$	—		$	17
(1) Information with respect to these model-priced financial assets and liabilities is provided above in a separate table.
(2) Fair value for these financial assets is measured using non-binding broker or dealer quotes.
31-Dec-13		Significant Unobservable Inputs Readily Available to State Street(1)			Significant Unobservable Inputs Not Developed by State Street and Not Readily Available(2)			Total Assets and Liabilities with Significant Unobservable Inputs
(In millions)
Assets:
U.S. Treasury and federal agencies, mortgage-backed securities		$	—		$	716		$	716
Asset-backed securities, student loans		13			410			423
Asset-backed securities, credit cards		24			—			24
Asset-backed securities, other		92			4,440			4,532
Non-U.S. debt securities, mortgage-backed securities		—			375			375
Non-U.S. debt securities, asset-backed securities		—			798			798
Non-U.S. debt securities, other		—			464			464
State and political subdivisions		43			—			43
Collateralized mortgage obligations		—			162			162
Other U.S.debt securities		—			8			8
Derivative instruments, foreign exchange contracts		19			—			19
Total		$	191		$	7,373		$	7,564
Liabilities:
Derivative instruments, foreign exchange contracts		$	17		$	—		$	17
Derivative instruments, other		9			—			9
Total		$	26		$	—		$	26
(1) Information with respect to these model-priced financial assets and liabilities is provided above in a separate table.
(2) Fair value for these financial assets is measured using non-binding broker or dealer quotes.
Internally-developed pricing models used to measure the fair value of our level-3 financial assets and liabilities incorporate discounted cash flow and option modeling techniques. Use of these techniques requires the determination of relevant inputs and assumptions, some of which represent significant unobservable inputs as indicated in the preceding table. Accordingly, changes in these unobservable inputs may have a significant impact on fair value.
Certain of these unobservable inputs will, in isolation, have a directionally consistent impact on the fair value of the instrument for a given change in that input. Alternatively, the fair value of the instrument may move in an opposite direction for a given change in another input. Where multiple inputs are used within the valuation technique of an asset or liability, a change in one input in a certain direction may be offset by an opposite change in another input, resulting in a potentially muted impact on the overall fair value of that particular instrument. Additionally, a change in one unobservable input may result in a change to another unobservable input (that is, changes in certain inputs are interrelated to one another), which may counteract or magnify the fair-value impact.
For recurring level-3 fair-value measurements for which significant unobservable inputs were readily available to State Street as of March 31, 2014, the sensitivity of the fair-value measurement to changes in significant unobservable inputs, and a description of any interrelationships between those unobservable inputs, is described below; however, we rarely experience a situation in which those unobservable inputs change in isolation:
•	The significant unobservable input used in the measurement of the fair value of our asset-backed securities and municipal securities (state and political subdivisions) is the credit spread. Significant increases (decreases) in the credit spread would result in measurements of significantly lower (higher) fair value of these securities.
•	The significant unobservable input used in the measurement of the fair value of our foreign exchange option contracts is the implied volatility surface. A significant increase (decrease) in the implied volatility surface would result in measurements of significantly higher (lower) fair value of these contracts.
•	The significant unobservable input used in the measurement of the fair value of our other derivative instruments, specifically stable value wrap contracts, is participant redemptions. Increased volatility of participant redemptions may result in changes to our measurement of fair value. Generally, significant increases (decreases) in participant redemptions may result in measurements of significantly higher (lower) fair value of this liability.
Fair Values of Financial Instruments:
Estimates of fair value for financial instruments not carried at fair value on a recurring basis in our consolidated statement of condition, as defined by GAAP, are generally subjective in nature, and are determined as of a specific point in time based on the characteristics of the financial instruments and relevant market information. Disclosure of fair-value estimates is not required by GAAP for certain items, such as lease financing, equity-method investments, obligations for pension and other post-retirement plans, premises and equipment, other intangible assets and income-tax assets and liabilities. Accordingly, aggregate fair-value estimates presented do not purport to represent, and should not be considered representative of, our underlying “market” or franchise value. In addition, because of potential differences in methodologies and assumptions used to estimate fair values, our estimates of fair value should not be compared to those of other financial institutions.
We use the following methods to estimate the fair values of our financial instruments:
•	For financial instruments that have quoted market prices, those quoted prices are used to estimate fair value.
•	For financial instruments that have no defined maturity, have a remaining maturity of 180 days or less, or reprice frequently to a market rate, we assume that the fair value of these instruments approximates their reported value, after taking into consideration any applicable credit risk.
•	For financial instruments for which no quoted market prices are available, fair value is estimated using information obtained from independent third parties, or by discounting the expected cash flows using an estimated current market interest rate for the financial instrument.
The generally short duration of certain of our assets and liabilities results in a significant number of financial instruments for which fair value equals or closely approximates the amount recorded in our consolidated statement of condition. These financial instruments are reported in the following captions in our consolidated statement of condition: cash and due from banks; interest-bearing deposits with banks; securities purchased under resale agreements; accrued interest and fees receivable; deposits; securities sold under repurchase agreements; federal funds purchased; and other short-term borrowings.
In addition, due to the relatively short duration of certain of our net loans (excluding leases), we consider fair value for these loans to approximate their reported value. The fair value of other types of loans, such as senior secured bank loans, commercial real estate loans and purchased receivables, is estimated using information obtained from independent third parties or by discounting expected future cash flows using current rates at which similar loans would be made to borrowers with similar credit ratings for the same remaining maturities. Commitments to lend have no reported value because their terms are at prevailing market rates.
The following tables present the reported amounts and estimated fair values of the financial instruments defined by GAAP, excluding financial assets and liabilities carried at fair value on a recurring basis, as they would be categorized within the fair-value hierarchy, as of the dates indicated.
								Fair-Value Hierarchy
31-Mar-14		Reported Amount			Estimated Fair Value			Quoted Market Prices in Active Markets (Level 1)				Pricing Methods with Significant Observable Market Inputs (Level 2)			Pricing Methods with Significant Unobservable Market Inputs (Level 3)
(In millions)
Financial Assets:
Cash and due from banks		$	3,877		$	3,877		$	3,877			$	—		$	—
Interest-bearing deposits with banks		75,796			75,796			—				75,796			—
Securities purchased under resale agreements		6,087			6,087			—				6,087			—
Investment securities held to maturity		18,342			18,326			—				18,326			—
Net loans (excluding leases)		14,994			15,002			—				14,530			472
Financial Liabilities:
Deposits:
Noninterest-bearing		$	72,800		$	72,800		$	—			$	72,800		$	—
Interest-bearing - U.S.		15,327			15,327			—				15,327			—
Interest-bearing - non-U.S.		106,521			106,521			—				106,521			—
Securities sold under repurchase agreements		8,953			8,953			—				8,953			—
Federal funds purchased		18			18			—				18			—
Other short-term borrowings		3,811			3,811			—				3,811			—
Long-term debt		9,503			9,809			—				8,927			882
								Fair-Value Hierarchy
31-Dec-13		Reported Amount			Estimated Fair Value			Quoted Market Prices in Active Markets (Level 1)				Pricing Methods with Significant Observable Market Inputs (Level 2)			Pricing Methods with Significant Unobservable Market Inputs (Level 3)
(In millions)
Financial Assets:
Cash and due from banks		$	3,220		$	3,220		$	3,220			$	—		$	—
Interest-bearing deposits with banks		64,257			64,257			—				64,257			—
Securities purchased under resale agreements		6,230			6,230			—				6,230			—
Investment securities held to maturity		17,740			17,560			—				17,560			—
Net loans (excluding leases)		12,363			12,355			—				11,908			447
Financial Liabilities:
Deposits:
Noninterest-bearing		$	65,614		$	65,614		$	—			$	65,614		$	—
Interest-bearing - U.S.		13,392			13,392			—				13,392			—
Interest-bearing - non-U.S.		103,262			103,262			—				103,262			—
Securities sold under repurchase agreements		7,953			7,953			—				7,953			—
Federal funds purchased		19			19			—				19			—
Other short-term borrowings		3,780			3,780			—				3,780			—
Long-term debt		9,699			9,909			—				9,056			853

Investment_Securities

Investment Securities	3 Months Ended
	Mar. 31, 2014
Investments, Debt and Equity Securities [Abstract]	'
Investment Securities	'
	Investment Securities
	The following table presents the amortized cost and fair value, and associated unrealized gains and losses, of investment securities as of the dates indicated:
		March 31, 2014										December 31, 2013
		Amortized			Gross					Fair		Amortized		Gross				Fair
		Cost			Unrealized					Value		Cost		Unrealized				Value
	(In millions)				Gains			Losses						Gains		Losses
	Available for sale:
	U.S. Treasury and federal agencies:
	Direct obligations	$	1,959		$	10		$	6	$	1,963	$	702	$	9	$	2	$	709
	Mortgage-backed securities	23,176			206			290		23,092		23,744		211		392		23,563
	Asset-backed securities:
	Student loans(1)	14,355			128			203		14,280		14,718		92		268		14,542
	Credit cards	7,253			21			37		7,237		8,230		21		41		8,210
	Sub-prime	1,234			3			82		1,155		1,291		3		91		1,203
	Other	4,767			133			20		4,880		4,949		138		23		5,064
	Total asset-backed securities	27,609			285			342		27,552		29,188		254		423		29,019
	Non-U.S. debt securities:
	Mortgage-backed securities	10,978			225			7		11,196		10,808		230		9		11,029
	Asset-backed securities	4,973			23			2		4,994		5,369		23		2		5,390
	Government securities	3,689			3			—		3,692		3,759		2		—		3,761
	Other	4,931			62			9		4,984		4,679		59		11		4,727
	Total non-U.S. debt securities	24,571			313			18		24,866		24,615		314		22		24,907
	State and political subdivisions	10,345			216			117		10,444		10,301		160		198		10,263
	Collateralized mortgage obligations	5,253			67			58		5,262		5,275		70		76		5,269
	Other U.S. debt securities	4,827			139			20		4,946		4,876		138		34		4,980
	U.S. equity securities	29			7			—		36		28		6		—		34
	Non-U.S. equity securities	1			—			—		1		1		—		—		1
	U.S. money-market mutual funds	993			—			—		993		422		—		—		422
	Non-U.S. money-market mutual funds	7			—			—		7		7		—		—		7
	Total	$	98,770		$	1,243		$	851	$	99,162	$	99,159	$	1,162	$	1,147	$	99,174
	Held to maturity:
	U.S. Treasury and federal agencies:
	Direct obligations	$	5,096		$	—		$	328	$	4,768	$	5,041	$	—	$	448	$	4,593
	Mortgage-backed securities	81			6			—		87		91		6		—		97
	Asset-backed securities:
	Student loans(1)	1,889			5			2		1,892		1,627		—		10		1,617
	Credit cards	897			3			—		900		762		1		—		763
	Other	738			1			1		738		782		1		2		781
	Total asset-backed securities	3,524			9			3		3,530		3,171		2		12		3,161
	Non-U.S. debt securities:
	Mortgage-backed securities	4,323			172			29		4,466		4,211		150		48		4,313
	Asset-backed securities	2,399			19			—		2,418		2,202		19		—		2,221
	Government securities	2			—			—		2		2		—		—		2
	Other	192			—			—		192		192		—		—		192
	Total non-U.S. debt securities	6,916			191			29		7,078		6,607		169		48		6,728
	State and political subdivisions	16			—			—		16		24		1		—		25
	Collateralized mortgage obligations	2,709			163			25		2,847		2,806		176		26		2,956
	Total	$	18,342		$	369		$	385	$	18,326	$	17,740	$	354	$	534	$	17,560
	(1) Substantially composed of securities guaranteed by the federal government with respect to at least 97% of defaulted principal and
	accrued interest on the underlying loans.
	Aggregate investment securities carried at $47.67 billion and $46.99 billion as of March 31, 2014 and December 31, 2013, respectively, were designated as pledged for public and trust deposits, short-term borrowings and for other purposes as provided by law.
	The following tables present the aggregate fair values of investment securities that have been in a continuous unrealized loss position for less than 12 months, and those that have been in a continuous unrealized loss position for 12 months or longer, as of the dates indicated:
		Less than 12 months						12 months or longer				Total
	March 31, 2014	Fair			Gross			Fair		Gross		Fair		Gross
		Value			Unrealized			Value		Unrealized		Value		Unrealized
	(In millions)				Losses					Losses				Losses
	Available for sale:
	U.S. Treasury and federal agencies:
	Direct obligations	$	1,433		$	5		$	130	$	1	$	1,563	$	6
	Mortgage-backed securities	9,475			197			3,161		93		12,636		290
	Asset-backed securities:
	Student loans	606			5			7,271		198		7,877		203
	Credit cards	3,311			26			214		11		3,525		37
Sub-prime	—			—			1,106		82		1,106		82
Other	1,997			10			418		10		2,415		20
Total asset-backed securities	5,914			41			9,009		301		14,923		342
Non-U.S. debt securities:
Mortgage-backed securities	819			2			326		5		1,145		7
Asset-backed securities	280			1			71		1		351		2
Other	1,652			6			149		3		1,801		9
Total non-U.S. debt securities	2,751			9			546		9		3,297		18
State and political subdivisions	1,850			49			1,311		68		3,161		117
Collateralized mortgage obligations	1,444			34			551		24		1,995		58
Other U.S. debt securities	783			13			60		7		843		20
Total	$	23,650		$	348		$	14,768	$	503	$	38,418	$	851
Held to maturity:
U.S. Treasury and federal agencies:
Direct obligations	$	4,751		$	328		$	—	$	—	$	4,751	$	328
Asset-backed securities:
Student loans	297			1			176		1		473		2
Other	129			1			—		—		129		1
Total asset-backed securities	426			2			176		1		602		3
Non-U.S. mortgage-backed securities	906			2			825		27		1,731		29
Collateralized mortgage obligations	595			11			407		14		1,002		25
Total	$	6,678		$	343		$	1,408	$	42	$	8,086	$	385
	Less than 12 months						12 months or longer				Total
December 31, 2013	Fair			Gross			Fair		Gross		Fair		Gross
	Value			Unrealized			Value		Unrealized		Value		Unrealized
(In millions)				Losses					Losses				Losses
Available for sale:
U.S. Treasury and federal agencies:
Direct obligations	$	182		$	1		$	113	$	1	$	295	$	2
Mortgage-backed securities	10,562			316			2,389		76		12,951		392
Asset-backed securities:
Student loans	1,930			16			7,252		252		9,182		268
Credit cards	3,714			30			161		11		3,875		41
Sub-prime	—			—			1,150		91		1,150		91
Other	1,896			12			439		11		2,335		23
Total asset-backed securities	7,540			58			9,002		365		16,542		423
Non-U.S. debt securities:
Mortgage-backed securities	868			2			258		7		1,126		9
Asset-backed securities	551			1			16		1		567		2
Other	1,655			9			150		2		1,805		11
Total non-U.S. debt securities	3,074			12			424		10		3,498		22
State and political subdivisions	3,242			113			1,268		85		4,510		198
Collateralized mortgage obligations	1,581			55			510		21		2,091		76
Other U.S. debt securities	1,039			25			58		9		1,097		34
Total	$	27,220		$	580		$	13,764	$	567	$	40,984	$	1,147
Held to maturity:
U.S. Treasury and federal agencies:
Direct obligations	$	4,571		$	448		$	—	$	—	$	4,571	$	448
Asset-backed securities:
Student Loans	1,352			10			—		—		1,352		10
Other	297			1			29		1		326		2
Total asset-backed securities	1,649			11			29		1		1,678		12
Non-U.S. mortgage-backed securities	834			3			878		45		1,712		48
Collateralized mortgage obligations	759			18			161		8		920		26
Total	$	7,813		$	480		$	1,068	$	54	$	8,881	$	534
The following table presents contractual maturities of debt investment securities as of March 31, 2014:
(In millions)	Under 1			1 to 5			6 to 10		Over 10
	Year			Years			Years		Years
Available for sale:
U.S. Treasury and federal agencies:
Direct obligations	$	2		$	526		$	835	$	600
Mortgage-backed securities	183			2,387			5,276		15,246
Asset-backed securities:
Student loans	647			6,608			4,216		2,809
Credit cards	2,187			3,057			1,993		—
Sub-prime	7			20			1		1,127
Other	469			1,314			1,381		1,716
Total asset-backed securities	3,310			10,999			7,591		5,652
Non-U.S. debt securities:
Mortgage-backed securities	1,698			5,562			247		3,689
Asset-backed securities	355			3,906			599		134
Government securities	2,537			1,155			—		—
Other	1,658			2,625			701		—
Total non-U.S. debt securities	6,248			13,248			1,547		3,823
State and political subdivisions	672			3,122			4,049		2,601
Collateralized mortgage obligations	453			1,458			1,059		2,292
Other U.S. debt securities	437			3,761			715		33
Total	$	11,305		$	35,501		$	21,072	$	30,247
Held to maturity:
U.S. Treasury and federal agencies:
Direct obligations	$	—		$	—		$	5,000	$	96
Mortgage-backed securities	—			19			16		46
Asset-backed securities
Student loans	19			192			383		1,295
Credit cards	—			335			562		—
Other	23			447			263		5
Total asset-backed securities	42			974			1,208		1,300
Non-U.S. debt securities:
Mortgage-backed securities	23			1,191			194		2,915
Asset-backed securities	70			2,085			244		—
Government securities	2			—			—		—
Other	166			25			—		1
Total non-U.S. debt securities	261			3,301			438		2,916
State and political subdivisions	13			3			—		—
Collateralized mortgage obligations	238			960			496		1,015
Total	$	554		$	5,257		$	7,158	$	5,373
The maturities of asset-backed securities, mortgage-backed securities and collateralized mortgage obligations are based on expected principal payments.
The following table presents gross realized gains and gross realized losses from sales of available-for-sale securities and the components of net impairment losses, included in net gains and losses related to investment securities, for the periods indicated:
	Three Months Ended March 31,
(In millions)	2014			2013
Gross realized gains from sales of available-for-sale securities	$	15		$	57
Gross realized losses from sales of available-for-sale securities	—			(52		)
Net impairment losses:
Gross losses from other-than-temporary impairment	(1		)	—
Losses reclassified (from) to other comprehensive income	(8		)	(3		)
Net impairment losses(1)	(9		)	(3		)
Gains related to investment securities, net	$	6		$	2
(1) Net impairment losses, recognized in our consolidated statement of income, were composed of the following:
Impairment associated with expected credit losses	$	(9	)	$	—
Impairment associated with adverse changes in timing of expected future cash flows	—			(3		)
Net impairment losses	$	(9	)	$	(3	)
The following table presents activity with respect to net impairment losses for the periods indicated:
	Three Months Ended March 31,
(In millions)	2014			2013
Beginning balance	$	122		$	124
Plus losses for which other-than-temporary impairment was previously recognized	9			3
Less previously recognized losses related to securities sold or matured	(1		)	—
Less losses related to securities intended or required to be sold	(6		)	—
Ending balance	$	124		$	127
Impairment:
We conduct periodic reviews of individual securities to assess whether other-than-temporary impairment exists. Impairment exists when the current fair value of an individual security is below its amortized cost basis. When the decline in the security's fair value is deemed to be other than temporary, the loss is recorded in our consolidated statement of income. In addition, for debt securities available for sale and held to maturity, impairment is recorded in our consolidated statement of income when management intends to sell (or may be required to sell) the securities before they recover in value, or when management expects the present value of cash flows expected to be collected from the securities to be less than the amortized cost of the impaired security (a credit loss).
Our review of impaired securities generally includes:
•	the identification and evaluation of securities that have indications of potential other-than-temporary impairment, such as issuer-specific concerns, including deteriorating financial condition or bankruptcy;
•	the analysis of expected future cash flows of securities, based on quantitative and qualitative factors;
•	the analysis of the collectability of those future cash flows, including information about past events, current conditions and reasonable and supportable forecasts;
•	the analysis of the underlying collateral for mortgage- and asset-backed securities;
•	the analysis of individual impaired securities, including consideration of the length of time the security has been in an unrealized loss position, the anticipated recovery period, and the magnitude of the overall price decline;
•	discussion and evaluation of factors or triggers that could cause individual securities to be deemed other-than- temporarily impaired and those that would not support other-than-temporary impairment; and
•	documentation of the results of these analyses.
Factors considered in determining whether impairment is other than temporary include:
•	certain macroeconomic drivers;
•	certain industry-specific drivers;
•	the length of time the security has been impaired;
•	the severity of the impairment;
•	the cause of the impairment and the financial condition and near-term prospects of the issuer;
•	activity in the market with respect to the issuer's securities, which may indicate adverse credit conditions; and
•	our intention not to sell, and the likelihood that we will not be required to sell, the security for a period of time sufficient to allow for its recovery in value.
Substantially all of our investment securities portfolio is composed of debt securities. A critical component of our assessment of other-than-temporary impairment of these debt securities is the identification of credit-impaired securities for which management does not expect to receive cash flows sufficient to recover the entire amortized cost basis of the security.
Debt securities that are not deemed to be credit-impaired are subject to additional management analysis to assess whether management intends to sell, or, more likely than not, would be required to sell, the security before the expected recovery to its amortized cost basis.
The following describes our process for the identification and assessment of other-than-temporary impairment.
U.S. Agency Residential Mortgage-Backed Securities
Our portfolio of U.S. agency residential mortgage-backed securities receives the implicit or explicit backing of the U.S. government in conjunction with specified financial support of the U.S. Treasury. We recorded no other-than-temporary impairment on these securities in the three months ended March 31, 2014 or the three months ended March 31, 2013. The decline in the unrealized losses on these securities as of March 31, 2014 compared to December 31, 2013 was attributable to narrowing spreads in the three months ended March 31, 2014.
Asset-Backed Securities - Student Loans
Asset-backed securities collateralized by student loans are primarily composed of securities collateralized by Federal Family Education Loan Program, or FFELP, loans. FFELP loans benefit from a federal government guarantee of at least 97% of defaulted principal and accrued interest, with additional credit support provided in the form of over-collateralization, subordination and excess spread, which collectively total in excess of 100%. Accordingly, the vast majority of FFELP loan-backed securities are protected from traditional consumer credit risk.
We recorded no other-than-temporary impairment on these securities in the three months ended March 31, 2014 or the three months ended March 31, 2013. The gross unrealized losses in our FFELP loan-backed securities portfolio as of March 31, 2014 were primarily attributable to lower liquidity and the lower spreads on these securities relative to those associated with more current issuances. Our assessment of other-than-temporary impairment of these securities considers, among many other factors, the strength of the U.S. government guarantee, the performance of the underlying collateral, and the remaining average term of the FFELP loan-backed securities portfolio, which was approximately 4.8 years as of March 31, 2014.
Our total exposure to private student loan-backed securities was less than $800 million as of March 31, 2014. Our assessment of other-than-temporary impairment of private student loan-backed securities considers, among other factors, the impact of high unemployment rates on the collateral performance of private student loans. We recorded no other-than-temporary impairment on these securities in the three months ended March 31, 2014 or the three months ended March 31, 2013.
Non-U.S. Mortgage- and Asset-Backed Securities
Non-U.S. mortgage- and asset-backed securities are primarily composed of U.K., Australian and Dutch securities collateralized by residential mortgages and German securities collateralized by automobile loans and leases. Our assessment of impairment with respect to these securities considers the location of the underlying collateral, collateral enhancement and structural features, expected credit losses under base-case and stressed conditions and the macroeconomic outlook for the country in which the collateral is located, including housing prices and unemployment. Where appropriate, any potential loss after consideration of the above-referenced factors is further evaluated to determine whether any other-than-temporary impairment exists.
In the three months ended March 31, 2014, we recorded no other-than-temporary impairment on these securities in our consolidated statement of income. In the three months ended March 31, 2013, we recorded other-than-temporary impairment of $3 million related to non-U.S. mortgage-backed securities resulting from adverse changes in the timing of expected future cash flows from certain of the securities.
Our aggregate exposure to Spain, Italy, Ireland and Portugal with respect to mortgage- and asset-backed securities totaled approximately $647 million as of March 31, 2014, composed of $204 million in Spain, $243 million in Italy, $120 million in Ireland and $80 million in Portugal. We had no direct sovereign debt exposure to any of these countries as of that date. As of March 31, 2014, these mortgage- and asset-backed securities had an aggregate pre-tax net unrealized gain of approximately $91 million, composed of gross unrealized gains of $96 million and gross unrealized losses of $5 million.
Our assessment of other-than-temporary impairment of these securities takes into account government intervention in the corresponding mortgage markets and assumes a negative baseline macroeconomic environment for this region, due to a combination of slower economic growth and continued government austerity measures. Our baseline view assumes a recessionary period characterized by high unemployment and by additional housing price declines of between 10% and 19% across these four countries. Our evaluation of other-than-temporary impairment in our base case does not assume a disorderly sovereign-debt restructuring or a break-up of the Eurozone. In addition, stress testing and sensitivity analysis is performed in order to understand the impact of more severe assumptions on potential other-than-temporary impairment.
State and Political Subdivisions and Other U.S. Debt Securities
Our municipal securities portfolio primarily includes securities issued by U.S. states and their municipalities. A portion of this portfolio is held in connection with our tax-exempt investment program, more fully described in note 9. Our portfolio of other U.S. debt securities is primarily composed of securities issued by U.S. corporations.  The decline in the unrealized losses on these securities as of March 31, 2014 compared to December 31, 2013 was attributable to narrowing spreads and declines in interest rates in the three months ended March 31, 2014.
Our assessment of other-than-temporary impairment of these portfolios considers, among other factors, adverse conditions specifically related to the industry, geographic area or financial condition of the issuer; the structure of the security, including collateral, if any, and payment schedule; rating agency changes to the security's credit rating; the volatility of the fair value changes; and our intent and ability to hold the security until its recovery in value.  If the impairment of the security is credit-related, we estimate the future cash flows from the security, tailored to the security and considering the above-described factors, and any resulting impairment deemed to be other than temporary is recorded in our consolidated statement of income.  We recorded no other-than-temporary impairment on these securities in the three months ended March 31, 2014 or 2013.
U.S. Non-Agency Residential Mortgage-Backed Securities
For U.S. non-agency residential mortgage-backed securities, we assess other-than-temporary impairment using cash-flow models, tailored for each security, that estimate the future cash flows from the underlying mortgages, using the security-specific collateral and transaction structure. Estimates of future cash flows are subject to management judgment. The future cash flows and performance of our portfolio of U.S. non-agency residential mortgage-backed securities are a function of a number of factors, including, but not limited to, the condition of the U.S. economy, the condition of the U.S. residential mortgage markets, and the level of loan defaults, prepayments and loss severities. Management's estimates of future losses for each security also consider the underwriting and historical performance of each specific security, the underlying collateral type, vintage, borrower profile, third-party guarantees, current levels of subordination, geography and other factors.
We recorded no other-than-temporary impairment on these securities in the three months ended March 31, 2014 or 2013.
U.S. Non-Agency Commercial Mortgage-Backed Securities
With respect to our portfolio of U.S. non-agency commercial mortgage-backed securities, other-than-temporary impairment is assessed by considering a number of factors, including, but not limited to, the condition of the U.S. economy and the condition of the U.S. commercial real estate market, as well as capitalization rates. Management estimates of future losses for each security also consider the underlying collateral type, property location, vintage, debt-service coverage ratios, expected property income, servicer advances and estimated property values, as well as current levels of subordination. We recorded $9 million of other-than-temporary impairment on these securities in our consolidated statement of income in the three months ended March 31, 2014, all associated with expected credit losses. We recorded no other-than-temporary impairment on these securities in the three months ended March 31, 2013.
*****
The estimates, assumptions and other risk factors utilized in our assessment of impairment as described above are used by management to identify securities which are subject to further analysis of potential credit losses. Additional analyses are performed using more stressful assumptions to further evaluate the sensitivity of losses relative to the above-described factors. However, since the assumptions are based on the unique characteristics of each security, management uses a range of estimates for prepayment speeds, default, and loss severity forecasts that reflect the collateral profile of the securities within each asset class. In addition, in measuring expected credit losses, the individual characteristics of each security are examined to determine whether any additional factors would increase or mitigate the expected loss. Once losses are determined, the timing of the loss will also affect the ultimate other-than-temporary impairment, since the loss is ultimately subject to a discount commensurate with the purchase yield of the security.
In the aggregate, we recorded other-than-temporary impairment of $9 million in the three months ended March 31, 2014, compared to $3 million in the three months ended March 31, 2013, respectively, as summarized below:
Three months ended March 31, 2014:
•	$9 million (U.S. non-agency commercial mortgage-backed securities) was associated with expected credit losses.
Three months ended March 31, 2013:
•	$3 million (non-U.S. mortgage-backed securities) resulted from adverse changes in the timing of expected future cash flows from certain of the securities.
After a review of the investment portfolio, taking into consideration current economic conditions, adverse situations that might affect our ability to fully collect principal and interest, the timing of future payments, the credit quality and performance of the collateral underlying mortgage- and asset-backed securities and other relevant factors, and excluding other-than-temporary impairment recorded in the three months ended March 31, 2014, management considers the aggregate decline in fair value of the investment securities portfolio and the resulting gross pre-tax unrealized losses of $1.24 billion as of March 31, 2014, related to 2,122 securities, to be temporary, and not the result of any material changes in the credit characteristics of the securities.

Loans_and_Leases

Loans and Leases	3 Months Ended
	Mar. 31, 2014
Loans and Leases Receivable Disclosure [Abstract]	'
Loans and Leases	'
	Loans and Leases
	The following table presents our recorded investment in loans and leases, by segment and class, as of the dates indicated:
	(In millions)	March 31, 2014			December 31, 2013
	Institutional:
	Investment funds:
	U.S.	$	10,000		$	8,695
	Non-U.S.	2,310			1,718
	Commercial and financial:
	U.S.	1,895			1,372
	Non-U.S.	363			154
	Purchased receivables:
	U.S.	202			217
	Non-U.S.	20			26
	Lease financing:
	U.S.	337			339
	Non-U.S.	753			756
	Total institutional	15,880			13,277
	Commercial real estate:
	U.S.	234			209
	Total loans and leases	16,114			13,486
	Allowance for loan losses	(30		)	(28		)
	Loans and leases, net of allowance for loan losses	$	16,084		$	13,458
	Aggregate short-duration advances to our clients included in the institutional segment were $4.83 billion and $2.45 billion as of March 31, 2014 and December 31, 2013, respectively.
	The commercial-and-financial class in the institutional segment presented in the table above included approximately $1.15 billion and $724 million of senior secured bank loans as of March 31, 2014 and December 31, 2013, respectively. These commercial-and-financial loans are included in the “speculative” category in the credit-quality-indicator tables presented below. As of March 31, 2014, our allowance for loan losses included approximately $8 million related to these loans.
	The commercial real estate, or CRE, segment is composed of the loans acquired in 2008 pursuant to indemnified repurchase agreements with an affiliate of Lehman as a result of the Lehman Brothers bankruptcy. These loans, which are primarily collateralized by direct and indirect interests in commercial real estate, were recorded at their then-current fair value, based on management’s expectations with respect to future cash flows from the loans using appropriate market discount rates as of the date of acquisition. These cash flow estimates are updated quarterly to reflect changes in management’s expectations, which consider market conditions and other factors.
	The following tables present our recorded investment in each class of loans and leases by credit quality indicator as of the dates indicated:
		Institutional										Commercial Real Estate
	March 31, 2014	Investment			Commercial and Financial			Purchased		Lease		Property Development		Other		Total
		Funds						Receivables		Financing						Loans and
	(In millions)															Leases
	Investment grade(1)	$	12,073		$	961		$	222	$	1,037	$	—	$	29	$	14,322
	Speculative(2)	237			1,281			—		53		205		—		1,776
	Special mention(3)	—			16			—		—		—		—		16
	Total	$	12,310		$	2,258		$	222	$	1,090	$	205	$	29	$	16,114
		Institutional										Commercial Real Estate
	December 31, 2013	Investment			Commercial and Financial			Purchased		Lease		Property Development		Other		Total
		Funds						Receivables		Financing						Loans and
	(In millions)															Leases
	Investment grade(1)	$	10,282		$	740		$	243	$	1,068	$	—	$	29	$	12,362
	Speculative(2)	131			770			—		27		180		—		1,108
	Special mention(3)	—			16			—		—		—		—		16
	Total	$	10,413		$	1,526		$	243	$	1,095	$	180	$	29	$	13,486
	(1) Investment-grade loans and leases consist of counterparties with strong credit quality and low expected credit risk and probability of default. Ratings apply to counterparties with a strong capacity to support the timely repayment of any financial commitment.
	(2) Speculative loans and leases consist of counterparties that face ongoing uncertainties or exposure to business, financial, or economic downturns. However, these counterparties may have financial flexibility or access to financial alternatives, which allow for financial commitments to be met.
	(3) Special mention loans and leases consist of counterparties with potential weaknesses that, if uncorrected, may result in deterioration of repayment prospects.
	Loans and leases are categorized in the rating categories presented in the preceding table that align with our internal risk-rating framework. Management considers the ratings to be current as of March 31, 2014. We use an internal risk-rating system to assess our risk of credit loss for each loan or lease. This risk-rating process incorporates the use of risk-rating tools in conjunction with management judgment. Qualitative and quantitative inputs are captured in a systematic manner, and following a formal review and approval process, an internal credit rating based on our credit scale is assigned.
	In assessing the risk rating assigned to each individual loan or lease, among the factors considered are the borrower's debt capacity, collateral coverage, payment history and delinquency experience, financial flexibility and earnings strength, the expected amounts and sources of repayment, the level and nature of contingencies, if any, and the industry and geography in which the borrower operates. These factors are based on an evaluation of historical and current information, and involve subjective assessment and interpretation. Credit counterparties are evaluated and risk-rated on an individual basis at least annually.
	The following table presents our recorded investment in loans and leases, disaggregated based on our impairment methodology, as of the dates indicated:
		March 31, 2014								December 31, 2013
	(In millions)	Institutional			Commercial Real Estate			Total Loans and Leases		Institutional		Commercial Real Estate		Total Loans and Leases
	Loans and leases:
	Individually evaluated for impairment	$	—		$	130		$	130	$	26	$	180	$	206
	Collectively evaluated for impairment(1)	15,880			104			15,984		13,251		29		13,280
	Total	$	15,880		$	234		$	16,114	$	13,277	$	209	$	13,486
	(1) As of March 31, 2014 and December 31, 2013, all of the allowance for loan losses of $30 million and $28 million, respectively, related to institutional loans collectively evaluated for impairment.
	The following tables present information related to our recorded investment in impaired loans and leases as of the dates, or for the periods, indicated:
		March 31, 2014								December 31, 2013
	(In millions)	Recorded Investment			Unpaid			Related Allowance(1)		Recorded Investment		Unpaid		Related Allowance(1)
					Principal							Principal
					Balance							Balance
	With no related allowance recorded:
	CRE—property development	$	130		$	143		$	—	$	130	$	143	$	—
	CRE—property development—acquired credit-impaired	—			34			—		—		34		—
CRE—other—acquired credit-impaired	—			21			—		—		21		—
Total CRE	$	130		$	198		$	—	$	130	$	198	$	—
(1) As of March 31, 2014 and December 31, 2013, all of the allowance for loan losses of $30 million and $28 million, respectively, related to loans that were not impaired.
	Three Months Ended March 31,
	Average Recorded Investment						Interest Revenue Recognized
	2014			2013			2014		2013
(In millions)
With no related allowance recorded:
CRE—property development	$	130		$	195		$	2	$	4
Total CRE	$	130		$	195		$	2	$	4
As of both March 31, 2014 and December 31, 2013, we held an aggregate of approximately $130 million of CRE loans, presented in the preceding impaired loans and leases table, which were modified in troubled debt restructurings. No impairment loss was recognized as a result of restructuring the loans, as the discounted cash flows of the modified loans exceeded the carrying amount of the original loans as of the modification date. No loans were modified in troubled debt restructurings in the three months ended March 31, 2014 or the year ended December 31, 2013.
The following table presents activity in the allowance for loan losses for the periods indicated:
	Three Months Ended March 31,
	2014								2013
(In millions)	Institutional			Commercial			Total Loans and Leases		Institutional		Commercial		Total Loans and Leases
				Real Estate							Real Estate
Allowance for loan losses:
Beginning balance	$	28		$	—		$	28	$	22	$	—	$	22
Provisions	2			—			2		—		—		—
Ending balance	$	30		$	—		$	30	$	22	$	—	$	22
The provision recorded in the three months ended March 31, 2014 was associated with our exposure to senior secured bank loans. These loans are held in connection with our participation in loan syndications in the non-investment-grade lending market.
Loans and leases are reviewed on a regular basis, and any provisions for loan losses that are recorded reflect management's estimate of the amount necessary to maintain the allowance for loan losses at a level considered appropriate to absorb estimated incurred losses in the loan-and-lease portfolio.

Goodwill_and_Other_Intangible_

Goodwill and Other Intangible Assets	3 Months Ended
	Mar. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill and Other Intangible Assets	'
	Goodwill and Other Intangible Assets
	The following table presents changes in the carrying amount of goodwill during the periods indicated:
		Three Months Ended March 31,
		2014									2013
	(In millions)	Investment			Investment			Total			Investment			Investment			Total
		Servicing			Management						Servicing			Management
	Goodwill:
	Beginning balance	$	5,999		$	37		$	6,036		$	5,941		$	36		$	5,977
	Foreign currency translation, net	2			—			2			(64		)	(1		)	(65		)
	Ending balance	$	6,001		$	37		$	6,038		$	5,877		$	35		$	5,912
	The following table presents changes in the net carrying amount of other intangible assets during the periods indicated:
		Three Months Ended March 31,
		2014									2013
	(In millions)	Investment			Investment			Total			Investment			Investment			Total
		Servicing			Management						Servicing			Management
	Other intangible assets:
	Beginning balance	$	2,321		$	39		$	2,360		$	2,492		$	47		$	2,539
	Amortization	(52		)	(2		)	(54		)	(51		)	(2		)	(53		)
	Foreign currency translation, net	—			—			—			(32		)	(2		)	(34		)
	Ending balance	$	2,269		$	37		$	2,306		$	2,409		$	43		$	2,452
	The following table presents the gross carrying amount, accumulated amortization and net carrying amount of other intangible assets by type as of the dates indicated:
		March 31, 2014									December 31, 2013
	(In millions)	Gross			Accumulated			Net			Gross			Accumulated			Net
		Carrying			Amortization			Carrying			Carrying			Amortization			Carrying
		Amount						Amount			Amount						Amount
	Client relationships	$	2,702		$	(1,011	)	$	1,691		$	2,706		$	(975	)	$	1,731
	Core deposits	717			(200		)	517			717			(191		)	526
	Other	230			(132		)	98			234			(131		)	103
	Total	$	3,649		$	(1,343	)	$	2,306		$	3,657		$	(1,297	)	$	2,360

Other_Assets

Other Assets	3 Months Ended
	Mar. 31, 2014
Other Assets [Abstract]	'
Other Assets	'
	Other Assets
	The following table presents the components of other assets as of the dates indicated:
	(In millions)	March 31, 2014		December 31, 2013
	Collateral deposits, net	$	13,518	$	13,706
	Unrealized gains on derivative financial instruments, net	3,469		5,476
	Bank-owned life insurance	2,359		2,343
	Investments in joint ventures and other unconsolidated entities	1,712		1,644
	Accounts receivable	687		950
	Prepaid expenses	359		286
	Income taxes receivable	339		337
	Receivable for securities settlement	334		195
	Deferred tax assets, net of valuation allowance	249		263
	Receivable for securities sold	191		—
	Deposits with clearing organizations	183		177
	Other(1)	589		613
	Total	$	23,989	$	25,990
	(1)	Included other real estate owned of approximately $60 million and $59 million as of March 31, 2014 and December 31, 2013, respectively.

Contingencies

Contingencies	3 Months Ended
	Mar. 31, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Contingencies	'
	Contingencies
	Legal and Regulatory Matters:
	In the ordinary course of business, we and our subsidiaries are involved in disputes, litigation, and governmental or regulatory inquiries and investigations, both pending and threatened. These matters, if resolved adversely against us or settled, may result in monetary damages, fines and penalties or require changes in our business practices. The resolution or settlement of these matters is inherently difficult to predict. Based on our assessment of these pending matters, we do not believe that the amount of any judgment, settlement or other action arising from any pending matter is likely to have a material adverse effect on our consolidated financial condition.  However, an adverse outcome in certain of the matters described below could have a material adverse effect on our consolidated results of operations for the period in which such matter is resolved, or an accrual is determined to be required on our consolidated financial condition, or on our reputation.
	We evaluate our needs for accruals of loss contingencies related to legal proceedings on a case-by-case basis. When we have a liability that we deem probable and that we deem can be reasonably estimated as of the date of our consolidated financial statements, we accrue for our estimate of the loss. We also consider a loss probable and establish an accrual when we make or intend to make an offer of settlement. Once established, an accrual is subject to subsequent adjustment as a result of additional information. The resolution of proceedings and the reasonably estimable loss (or range thereof) are inherently difficult to predict, especially in the early stages of proceedings. Even if a loss is probable, due to many complex factors, such as speed of discovery and the timing of court decisions or rulings, a loss or range of loss might not be reasonably estimated until the later stages of the proceeding.
	As of March 31, 2014, our aggregate accruals for legal loss contingencies and regulatory matters totaled approximately $111 million. To the extent that we have established accruals in our consolidated statement of condition for probable loss contingencies, such accruals may not be sufficient to cover our ultimate financial exposure associated with any settlements or judgments. We may be subject to proceedings in the future that, if adversely resolved, would have a material adverse effect on our businesses or on our future consolidated financial statements. Except where otherwise noted below, we have not established accruals with respect to the claims discussed and do not believe that potential exposure is probable and can be reasonably estimated.
	The following discussion provides information with respect to significant legal and regulatory matters.
	SSgA
	We have previously reported on two related ERISA class actions by investors in unregistered SSgA-managed collective trust funds and common trust funds which challenge the division of our securities lending-related revenue between those funds and State Street in its role as lending agent. In January 2014, we filed a motion to approve a $10 million class settlement of the collective trust fund litigation. A final fairness hearing has been scheduled for May 2014. The common trust fund class action was dismissed in March 2014.
	Securities Finance
	Two related participants in our agency securities lending program have brought suit against us challenging actions taken by us in response to their withdrawal from the program. We believe that certain withdrawals by these participants were inconsistent with the redemption policy applicable to the agency lending collateral pools and, consequently, redeemed their remaining interests through an in-kind distribution that reflected the assets these participants would have received had they acted in accordance with the collateral pools' redemption policy. In taking these actions, we believe that we acted in the best interests of all participants in the collateral pools. The two participants have asserted damages of $120 million, an amount that plaintiffs attribute to alleged deficiencies in the methodology that State Street used to construct the in-kind distribution and alleged errors in the pricing of the securities that plaintiffs received on or about August 2009. While management does not believe that such difference is an appropriate measure of damages, we have been informed that the participants liquidated these securities in June 2013, and we estimate the loss on those sales to be approximately $11 million. We had $10 million accrued as of March 31, 2014 in connection with this matter.
	Foreign Exchange
	We offer our custody clients and their investment managers the option to route foreign exchange transactions to our foreign exchange desk through our asset servicing operation. We record as revenue an amount approximately equal to the difference between the rates we set for those trades and indicative interbank market rates at the time of settlement of the trade. As discussed more fully below, claims have been asserted on behalf of certain current and former custody clients, and future claims may be asserted, alleging that our indirect foreign exchange rates (including the differences between those rates and indicative interbank market rates at the time we executed the trades) were not adequately disclosed or were otherwise improper, and seeking to recover, among other things, the full amount of the revenue we obtained from our indirect foreign exchange trading with them.
	In October 2009, the Attorney General of the State of California commenced an action under the California False Claims Act and California Business and Professional Code related to services State Street provides to California state pension plans. The California Attorney General asserts that the pricing of certain foreign exchange transactions for these pension plans was governed by the custody contracts for these plans and that our pricing was not consistent with the terms of those contracts and related disclosures to the plans, and that, as a result, State Street made false claims and engaged in unfair competition. The Attorney General asserts actual damages of approximately $100 million for periods from 2001 to 2009 and seeks additional penalties, including treble damages. This action is in the discovery phase.
	We provide custody and principal foreign exchange services to government pension plans in other jurisdictions. Since the commencement of the litigation in California, attorneys general and other government authorities from a number of jurisdictions, as well as U.S. Attorney's offices, the U.S. Department of Labor and the SEC, have requested information or issued subpoenas in connection with inquiries into the pricing of our foreign exchange services. We continue to respond to such inquiries and subpoenas.
	We offer indirect foreign exchange services such as those we offer to the California state pension plans to a broad range of custody clients in the U.S. and internationally. We have responded and are responding to information requests from a number of clients concerning our indirect foreign exchange rates. In February 2011, a putative class action was filed in federal court in Boston seeking unspecified damages, including treble damages, on behalf of all custodial clients that executed certain foreign exchange transactions with State Street from 1998 to 2009. The putative class action alleges, among other things, that the rates at which State Street executed foreign currency trades constituted an unfair and deceptive practice under Massachusetts law and a breach of the duty of loyalty.
	Two other putative class actions are currently pending in federal court in Boston alleging various violations of ERISA on behalf of all ERISA plans custodied with us that executed indirect foreign exchange transactions with State Street from 1998 onward. The complaints allege that State Street caused class members to pay unfair and unreasonable rates for indirect foreign exchange transactions with State Street. The complaints seek unspecified damages, disgorgement of profits, and other equitable relief.
	We have not established an accrual with respect to any of the pending legal proceedings related to our indirect foreign exchange services. We cannot provide any assurance as to the outcome of the pending proceedings, or whether other proceedings might be commenced against us by clients or government authorities. We expect that plaintiffs will seek to recover their share of all or a portion of the revenue that we have recorded from providing indirect foreign exchange services.
	The following table summarizes our estimated total revenue worldwide from indirect foreign exchange trading services for the periods indicated:
	(In millions)	Revenue from indirect foreign exchange trading
	2008	$	462
	2009	369
	2010	336
	2011	331
	2012	248
	2013	285
	Three Months Ended March 31, 2014	63
	We believe that the amount of our revenue from such services has been of a similar or lesser order of magnitude for many years prior to 2008. Our revenue calculations related to indirect foreign exchange trading services reflect a judgment concerning the relationship between the rates we charge for indirect foreign exchange execution and indicative interbank market rates near in time to execution. Our revenue from foreign exchange trading generally depends on the difference between the rates we set for indirect trades and indicative interbank market rates on the date trades settle.
	We cannot predict the outcome of any pending matters or whether a court, in the event of an adverse resolution, would consider our revenue to be the appropriate measure of damages.
	Shareholder Litigation
	Three shareholder-related complaints are currently pending in federal court in Boston. One complaint purports to be a class action on behalf of State Street shareholders. The two other complaints purport to be class actions on behalf of participants and beneficiaries in the State Street Salary Savings Program who invested in the program's State Street common stock investment option. The complaints allege various violations of the federal securities laws, common law and ERISA in connection with our public disclosures concerning our investment securities portfolio, our asset-backed commercial paper conduit program, and our foreign exchange trading business. A fourth complaint, a purported shareholder derivative action on behalf of State Street, was dismissed in September 2013. As of March 31, 2014, we had an accrual, net of anticipated insurance recovery, of $13 million in connection with this matter.
	Transition Management
	In January 2014, we entered into a settlement with the U.K. Financial Conduct Authority pursuant to which we paid a fine of £22.9 million (approximately $37.8 million), as a result of our having charged six clients of our U.K. transition management business during 2010 and 2011 amounts in excess of the contractual terms. The SEC and the U.S. Attorney are conducting separate investigations into this matter. As of March 31, 2014, we had remaining accruals of approximately $3 million for indemnification costs associated with this matter.
	Investment Servicing
	State Street is named as a defendant in related complaints by investment management clients of TAG Virgin Islands, Inc., or TAG, who hold or held custodial accounts with State Street. The complaints, collectively, allege various claims in connection with certain assets managed by TAG. In 2013, we entered into settlements with certain of the TAG account holders. We had $4.6 million accrued as of March 31, 2014 with respect to claims that have not been settled.
	Income Taxes:
	In determining our provision for income taxes, we make certain judgments and interpretations with respect to tax laws in jurisdictions in which we have business operations. Because of the complex nature of these laws, in the normal course of our business, we are subject to challenges from U.S. and non-U.S. income tax authorities regarding the amount of income taxes due. These challenges may result in adjustments to the timing or amount of taxable income or deductions or the allocation of taxable income among tax jurisdictions. We recognize a tax benefit when it is more likely than not that our position will result in a tax deduction or credit. Unrecognized tax benefits totaled approximately $163 million and $164 million as of March 31, 2014 and December 31, 2013, respectively.
	The Internal Revenue Service, or IRS, is currently reviewing our U.S. income tax returns for the tax years 2010 and 2011. Management believes that we have sufficiently accrued liabilities as of March 31, 2014 for tax exposures, including, but not limited to, exposures related to the review by the IRS of the tax years 2010 and 2011.

Commitments_and_Guarantees

Commitments and Guarantees	3 Months Ended
	Mar. 31, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Guarantees	'
	Commitments and Guarantees
	Commitments:
	We had unfunded off-balance sheet commitments to extend credit totaling $21.77 billion and $21.30 billion as of March 31, 2014 and December 31, 2013, respectively. The potential losses associated with these commitments equal the gross contractual amounts, and do not consider the value of any collateral. Approximately 77% of our unfunded commitments to extend credit expire within one year from the date of issue. Since many of these commitments are expected to expire or renew without being drawn upon, the gross contractual amounts do not necessarily represent our future cash requirements.
	Guarantees:
	Off-balance sheet guarantees are composed of indemnified securities financing, stable value protection, unfunded commitments to purchase assets, and standby letters of credit. The potential losses associated with these guarantees equal the gross contractual amounts, and do not consider the value of any collateral. The following table presents the aggregate gross contractual amounts of our off-balance sheet guarantees as of the dates indicated. Amounts presented do not reflect participations to independent third parties.
	(In millions)	March 31, 2014		December 31, 2013
	Indemnified securities financing	$	346,789	$	320,078
	Stable value protection	24,484		24,906
	Asset purchase agreements	4,304		4,685
	Standby letters of credit	4,870		4,612
	Indemnified Securities Financing
	On behalf of our clients, we lend their securities, as agent, to brokers and other institutions. In most circumstances, we indemnify our clients for the fair market value of those securities against a failure of the borrower to return such securities. We require the borrowers to maintain collateral in an amount equal to or in excess of 100% of the fair market value of the securities borrowed. Securities on loan and the collateral are revalued daily to determine if additional collateral is necessary or if excess collateral is required to be returned to the borrower. Collateral received in connection with our securities lending services is held by us as agent and is not recorded in our consolidated statement of condition.
	The cash collateral held by us as agent is invested on behalf of our clients. In certain cases, the cash collateral is invested in third-party repurchase agreements, for which we indemnify the client against loss of the principal invested. We require the counterparty to the indemnified repurchase agreement to provide collateral in an amount equal to or in excess of 100% of the amount of the repurchase agreement. In our role as agent, the indemnified repurchase agreements and the related collateral held by us are not recorded in our consolidated statement of condition.
	The following table summarizes the fair values of indemnified securities financing and related collateral, as well as collateral invested in indemnified repurchase agreements, as of the dates indicated:
	(In millions)	March 31, 2014		December 31, 2013
	Aggregate fair value of indemnified securities financing	$	346,789	$	320,078
	Aggregate fair value of cash and securities held by us, as agent, as collateral for indemnified securities financing	358,240		331,732
	Aggregate fair value of collateral for indemnified securities financing invested in indemnified repurchase agreements	94,423		85,374
	Aggregate fair value of cash and securities held by us or our agents as collateral for investments in indemnified repurchase agreements	99,935		91,097
	In certain cases, we participate in securities finance transactions as a principal. As a principal, we borrow securities from the lending client and then lend such securities to the subsequent borrower, either a State Street client or a broker/dealer. Collateral provided and received in connection with such transactions is recorded in other assets and accrued expenses and other liabilities, respectively, in our consolidated statement of condition. As of March 31, 2014 and December 31, 2013, we had approximately $11.32 billion and $11.29 billion, respectively, of collateral provided and approximately $6.29 billion and $6.62 billion, respectively, of collateral received from clients in connection with our participation in principal securities finance transactions.
	Stable Value Protection
	In the normal course of our business, we offer products that provide book-value protection, primarily to plan participants in stable value funds managed by non-affiliated investment managers of post-retirement defined contribution benefit plans, particularly 401(k) plans. The book-value protection is provided on portfolios of intermediate investment grade fixed-income securities, and is intended to provide safety and stable growth of principal invested. The protection is intended to cover any shortfall in the event that a significant number of plan participants withdraw funds when book value exceeds market value and the liquidation of the assets is not sufficient to redeem the participants. The investment parameters of the underlying portfolios, combined with structural protections, are designed to provide cushion and guard against payments even under extreme stress scenarios.
	These contingencies are individually accounted for as derivative financial instruments. The notional amounts of the stable value contracts are presented as “derivatives not designated as hedging instruments” in the table of aggregate notional amounts of derivative financial instruments provided in note 11. We have not made a payment under these contingencies that we consider material to our consolidated financial condition, and management believes that the probability of payment under these contingencies in the future, that we would consider material to our consolidated financial condition, is remote.

Variable_Interest_Entities

Variable Interest Entities	3 Months Ended
	Mar. 31, 2014
Variable Interest Entities [Abstract]	'
Variable Interest Entities	'
	Variable Interest Entities
	Asset-Backed Investment Securities:
	We invest in various forms of asset-backed securities, which we carry in our investment securities portfolio. These asset-backed securities meet the GAAP definition of asset securitization entities, which are considered to be variable interest entities, or VIEs, as defined by GAAP. We are not considered to be the primary beneficiary of these VIEs, as defined by GAAP, since we do not have control over their activities. Additional information about our asset-backed securities is provided in note 3.
	Tax-Exempt Investment Program:
	In the normal course of our business, we structure and sell certificated interests in pools of tax-exempt investment-grade assets, principally to our mutual fund clients. We structure these pools as partnership trusts, and the assets and liabilities of the trusts are recorded in our consolidated statement of condition as investment securities available for sale and other short-term borrowings. We may also provide liquidity and re-marketing services to the trusts. As of March 31, 2014 and December 31, 2013, we carried investment securities available for sale, composed of securities related to state and political subdivisions, with a fair value of $2.33 billion as of each date, and other short-term borrowings of $1.93 billion and $1.95 billion, respectively, in our consolidated statement of condition in connection with these trusts.
	We transfer assets to the trusts from our investment securities portfolio at adjusted book value, and the trusts finance the acquisition of these assets by selling certificated interests issued by the trusts to third-party investors and to State Street as residual holder. These transfers do not meet the de-recognition criteria defined by GAAP, and therefore, are recorded in our consolidated financial statements. The trusts had a weighted-average life of approximately 6.3 years as of March 31, 2014, compared to approximately 6.5 years as of December 31, 2013.
	Under separate legal agreements, we provide standby bond-purchase agreements to these trusts and, with respect to certain securities, letters of credit. Our commitments to the trusts under these standby bond-purchase agreements and letters of credit totaled $1.96 billion and $684 million, respectively, as of March 31, 2014, none of which was utilized as of that date. In the event that our obligations under these agreements are triggered, no material impact to our consolidated results of operations or financial condition is expected to occur, because the securities are already recorded at fair value in our consolidated statement of condition.
	Interests in Sponsored Investment Funds:
	In the normal course of business, we manage various types of sponsored investment funds through SSgA. The services we provide to these sponsored investment funds generate management fee revenue. From time to time, we may invest cash in the funds, which we refer to as seed capital, in order for the funds to establish a performance history for newly-launched strategies. These funds may be considered VIEs.
	As of March 31, 2014, we were an investor in a sponsored investment fund, considered to be a VIE, which was initially launched on December 31, 2013. Given the extent of our exposure to the variability of the net assets of the fund, we were deemed to be the fund’s primary beneficiary, and as a result we include the fund in our consolidated financial statements. The fund's activities consist primarily of active trading in various equity, fixed-income, currency, commodity and futures markets. Such activities are included in our consolidated financial statements.
	As of March 31, 2014, the aggregate assets and liabilities of this consolidated sponsored investment fund totaled $60 million and $10 million, respectively. As of December 31, 2013, the fund’s assets consisted solely of $50 million in cash.
	As of March 31, 2014 our potential maximum total exposure associated with the consolidated sponsored investment fund totaled $50 million and represented the value of our economic ownership interest in the fund. In the aggregate, we expect any financial losses that we realize over time from these seed investments to be limited to the actual fair value of the amount invested in the consolidated fund, which is based on the fair value of the underlying investment securities held by the funds. However, in the event of a fund wind-down, gross gains and losses of the fund may be recognized for financial accounting purposes in different periods during the time the fund is consolidated but not wholly owned. Although we expect the actual economic loss to be limited to the amount invested, our losses in any period could exceed the value of our economic interests in the fund and could exceed the value of our initial seed capital investment.
	Our conclusion to consolidate a sponsored investment fund may vary from period to period, most commonly as a result of fluctuation in our ownership interest as a result of changes in the number of fund shares held by either us or by third parties. Given that the funds follow specialized investment company accounting rules which prescribe fair value, a de-consolidation generally would not result in gains or losses for us.
	The net assets of any consolidated fund are solely available to settle the liabilities of the fund and to settle any investors’ ownership redemption requests, including any seed capital invested in the fund by State Street. We are not contractually required to provide financial or any other support to any of our sponsored investment funds. In addition, neither creditors nor equity investors in the sponsored investment funds have any recourse to State Street’s general credit.
	As of March 31, 2014 and December 31, 2013, we managed certain sponsored investment funds, considered VIEs, in which we held a variable interest but for which we were not deemed to be the primary beneficiary. Our potential maximum loss exposure related to these unconsolidated funds totaled $24 million and $18 million as of March 31, 2014 and December 31, 2013, respectively, and represented the carrying value of our seed capital investment, which is recorded in either investment securities available for sale or other assets in our consolidated statement of condition. The amount of loss we may recognize during any period is limited to the carrying amount of our seed capital investment in the unconsolidated fund.

Shareholders_Equity

Shareholders' Equity	3 Months Ended
	Mar. 31, 2014
Stockholders' Equity Note [Abstract]	'
Shareholders' Equity	'
	Shareholders’ Equity
	Preferred Stock:
	In February 2014, we issued 30 million depositary shares, each representing a 1/4,000th ownership interest in a share of State Street’s fixed-to-floating-rate non-cumulative perpetual preferred stock, Series D, without par value, with a liquidation preference of $100,000 per share (equivalent to $25 per depositary share), in a public offering. The aggregate proceeds from the offering, net of underwriting discounts, commissions and other issuance costs, were approximately $742 million.
	On March 15, 2024, or any dividend payment date thereafter, the Series D preferred stock and corresponding depositary shares may be redeemed by us, in whole or in part, at a redemption price equal to $100,000 per share (equivalent to $25 per depositary share) plus any declared and unpaid dividends, without accumulation of any undeclared dividends. The Series D preferred stock and corresponding depositary shares may be redeemed at our option in whole, but not in part, prior to March 15, 2024, upon the occurrence of a regulatory capital treatment event, as defined in the certificate of designation with respect to the Series D preferred stock, at a redemption price equal to $100,000 per share (equivalent to $25 per depositary share) plus any declared and unpaid dividends, without accumulation of any undeclared dividends.
	In the three months ended March 31, 2014, we declared aggregate dividends on our non-cumulative perpetual preferred stock, Series C (represented by depositary shares, each representing a 1/4,000th ownership interest in a share of State Street's non-cumulative perpetual preferred stock, Series C) of $1,313 per share, or approximately $0.33 per depositary share, totaling approximately $6 million.
	Dividends on shares of both our Series C and Series D preferred stock are not mandatory and are not cumulative. If declared, dividends will be payable on the liquidation preference of $100,000 per share quarterly in arrears on March 15, June 15, September 15 or December 15 of each year at an annual rate of 5.25% and 5.90%, respectively. If we issue additional shares of our Series C or Series D preferred stock after the original issue date, dividend rights with respect to such shares will commence from the original issue date of such additional shares. Dividends on our Series C and Series D preferred stock will not be declared to the extent that such declaration would cause us to fail to comply with applicable laws and regulations, including federal regulatory capital guidelines.
	On September 15, 2017, or any dividend payment date thereafter, the Series C preferred stock and corresponding depositary shares may be redeemed by us, in whole or in part, at a redemption price equal to $100,000 per share (equivalent to $25 per depositary share) plus any declared and unpaid dividends, without accumulation of any undeclared dividends. The Series C preferred stock and corresponding depositary shares may be redeemed at our option, in whole or in part, prior to September 15, 2017, upon the occurrence of a regulatory capital treatment event, as defined in the certificate of designation with respect to the Series C preferred stock, at a redemption price equal to $100,000 per share (equivalent to $25 per depositary share) plus any declared and unpaid dividends, without accumulation of any undeclared dividends.
	Common Stock:
	In March 2014, our Board of Directors approved a new common stock purchase program authorizing the purchase of up to $1.70 billion of our common stock through March 31, 2015. No shares were purchased by us under this program in the three months ended March 31, 2014.
	In the three months ended March 31, 2014, we purchased approximately 6.1 million shares of our common stock at an average cost of $69.14 per share and an aggregate cost of approximately $420 million, under a previous program approved by the Board in March 2013. As of March 31, 2014, no shares remained available for purchase under the March 2013 program. Shares acquired in connection with our common stock purchase programs which remained unissued as of March 31, 2014 were recorded as treasury stock in our consolidated statement of condition as of March 31, 2014.
	In both the three months ended March 31, 2014 and 2013, we declared aggregate common stock dividends of $0.26 per share, totaling approximately $112 million and $118 million, respectively.
	Accumulated Other Comprehensive Income (Loss):
	The following table presents the after-tax components of AOCI as of the dates indicated:
	(In millions)	March 31, 2014			December 31, 2013
	Net unrealized gains on cash flow hedges	$	154		$	161
	Net unrealized gains (losses) on available-for-sale securities portfolio	194			(56		)
	Net unrealized losses related to reclassified available-for-sale securities	(61		)	(72		)
	Net unrealized gains (losses) on available-for-sale securities	133			(128		)
	Net unrealized losses on available-for-sale securities designated in fair value hedges	(107		)	(97		)
	Other-than-temporary impairment on available-for-sale securities related to factors other than credit	2			4
	Net unrealized losses on hedges of net investments in non-U.S. subsidiaries	(14		)	(14		)
	Other-than-temporary impairment on held-to-maturity securities related to factors other than credit	(39		)	(47		)
	Net unrealized losses on retirement plans	(197		)	(203		)
	Foreign currency translation	256			229
	Total	$	188		$	(95	)
	In the three months ended March 31, 2014, we realized net gains of $15 million, or $9 million net of related taxes as presented in the tables that follow, from sales of available-for-sale securities. Unrealized pre-tax gains of $5 million were included in AOCI as of December 31, 2013, net of deferred taxes of $3 million, related to these sales. In the
	three months ended March 31, 2013, we realized net gains of $5 million, or $3 million net of related taxes as presented in the tables that follow, from sales of available-for-sale securities. Unrealized pre-tax losses of $49 million were included in AOCI as of December 31, 2012, net of deferred taxes of $20 million, related to these sales.
	The following tables presents changes in AOCI by component, net of related taxes, for the periods indicated:
		Three Months Ended March 31, 2014
	(In millions)	Net Unrealized Gains (Losses) on Cash Flow Hedges			Net Unrealized Gains (Losses) on Available-for-Sale Securities			Net Unrealized Losses on Hedges of Net Investments in Non-U.S. Subsidiaries			Other-Than-Temporary Impairment on Held-to-Maturity Securities			Net Unrealized Losses on Retirement Plans			Foreign Currency Translation			Total
	Beginning balance	$	161		$	(221	)	$	(14	)	$	(47	)	$	(203	)	$	229		$	(95	)
	Other comprehensive income (loss) before reclassifications	(8		)	258			—			8			1			27			286
	Amounts reclassified out of AOCI	1			(9		)	—			—			5			—			(3		)
	Other comprehensive income (loss)	(7		)	249			—			8			6			27			283
	Ending balance	$	154		$	28		$	(14	)	$	(39	)	$	(197	)	$	256		$	188
		Three Months Ended March 31, 2013
	(In millions)	Net Unrealized Gains (Losses) on Cash Flow Hedges			Net Unrealized Gains (Losses) on Available-for-Sale Securities			Net Unrealized Losses on Hedges of Net Investments in Non-U.S. Subsidiaries			Other-Than-Temporary Impairment on Held-to-Maturity Securities			Net Unrealized Losses on Retirement Plans			Foreign Currency Translation			Total
	Beginning balance	$	69		$	519		$	(14	)	$	(65	)	$	(283	)	$	134		$	360
	Other comprehensive income (loss) before reclassifications	63			69			—			4			(2		)	(248		)	(114		)
	Amounts reclassified out of AOCI	1			(3		)	—			2			5			—			5
	Other comprehensive income (loss)	64			66			—			6			3			(248		)	(109		)
	Ending balance	$	133		$	585		$	(14	)	$	(59	)	$	(280	)	$	(114	)	$	251
	The following table presents after-tax reclassifications out of AOCI for the periods indicated:
		Three Months Ended March 31,
		2014			2013
	(In millions)	Amounts Reclassified out of AOCI						Affected Line Item in Consolidated Statement of Income
	Cash flow hedges:
	Interest-rate contracts	$	1		$	1		Net interest revenue
	Available-for-sale securities:
	Net realized gains from sales of available-for-sale securities, net of related taxes of ($6) and ($2), respectively	(9		)	(3		)	Net gains (losses) from sales of available-for-sale securities
	Held-to-maturity securities:
	Other-than-temporary impairment on held-to-maturity securities related to factors other than credit, net of related tax benefit of $1	—			2			Losses reclassified (from) to other comprehensive income
	Retirement plans:
	Amortization of actuarial losses, net of related tax benefits of $3 and $3, respectively	5			5			Compensation and employee benefits expenses
	Total reclassifications out of AOCI	$	(3	)	$	5

Derivative_Financial_Instrumen

Derivative Financial Instruments	3 Months Ended
	Mar. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Derivative Financial Instruments	'
	Derivative Financial Instruments
	We use derivative financial instruments to support our clients' needs and to manage our interest-rate and currency risk. In undertaking these activities, we assume positions in both the foreign exchange and interest-rate markets by buying and
	selling cash instruments and using derivative financial instruments, including foreign exchange forward contracts, foreign exchange and interest-rate options and interest-rate swaps, interest-rate forward contracts and interest-rate futures. Our derivative positions include derivative contracts held by a consolidated sponsored investment fund (refer to note 9).
	Interest-rate contracts involve an agreement with a counterparty to exchange cash flows based on the movement of an underlying interest-rate index. An interest-rate swap agreement involves the exchange of a series of interest payments, at either a fixed or variable rate, based on the notional amount without the exchange of the underlying principal amount. An interest-rate option contract provides the purchaser, for a premium, the right, but not the obligation, to receive an interest rate based upon a predetermined notional amount during a specified period. An interest-rate futures contract is a commitment to buy or sell, at a future date, a financial instrument at a contracted price; it may be settled in cash or through the delivery of the contracted instrument.
	Foreign exchange contracts involve an agreement to exchange one currency for another currency at an agreed-upon rate and settlement date. Foreign exchange contracts generally consist of foreign exchange forward and spot contracts, option contracts and cross-currency swaps. Future cash requirements, if any, related to foreign exchange contracts are represented by the gross amount of currencies to be exchanged under each contract unless we and the counterparty have agreed to pay or to receive the net contractual settlement amount on the settlement date.
	Derivative financial instruments involve the management of interest-rate and foreign currency risk, and involve, to varying degrees, market risk and credit and counterparty risk (risk related to repayment). Market risk is defined by U.S. banking regulators as the risk of loss that could result from broad market movements, such as changes in the general level of interest rates, credit spreads, foreign exchange rates or commodity prices. We use a variety of risk management tools and methodologies to measure, monitor and manage the market risk associated with our trading activities, which trading activities include our use of derivative financial instruments. One such risk-management measure is Value-at-Risk, or VaR. VaR is an estimate of potential loss for a given period within a stated statistical confidence interval. We use a risk-measurement system to measure VaR daily. We have adopted standards for measuring VaR, and we maintain regulatory capital for market risk in accordance with currently applicable regulatory market risk requirements.
	Derivative financial instruments are also subject to credit and counterparty risk, which is defined as the risk of financial loss if a borrower or counterparty is either unable or unwilling to repay borrowings or settle a transaction in accordance with the underlying contractual terms. We manage credit and counterparty risk by performing credit reviews, maintaining individual counterparty limits, entering into netting arrangements and requiring the receipt of collateral. Collateral requirements are determined after a review of the creditworthiness of each counterparty, and these requirements are monitored and adjusted daily. Collateral is generally held in the form of cash or highly liquid U.S. government securities. We may be required to provide collateral to the counterparty in connection with our entry into derivative financial instruments. Cash collateral received from and provided to counterparties in connection with derivative financial instruments is recorded in accrued expenses and other liabilities and other assets, respectively, in our consolidated statement of condition. As of March 31, 2014 and December 31, 2013, we had recorded approximately $1.74 billion and $2.58 billion, respectively, of cash collateral received from counterparties and approximately $2.46 billion and $3.36 billion, respectively, of cash collateral provided to counterparties in connection with derivative financial instruments in our consolidated statement of condition.
	We enter into master netting agreements with many of our derivative counterparties, and we have elected to net derivative assets and liabilities, including cash collateral received or deposited, which are subject to those agreements. Certain of these agreements contain credit risk-related contingent features in which the counterparty has the right to declare State Street in default and accelerate cash settlement of our net derivative liabilities with the counterparty in the event that our credit rating falls below specified levels. The aggregate fair value of all derivative instruments with credit risk-related contingent features that were in a net liability position as of March 31, 2014 totaled approximately $422 million, against which we had provided no underlying collateral, due to timing differences with respect to the mark-to-market valuation of the collateral. If State Street’s credit rating were downgraded below levels specified in the agreements, the maximum additional amount of payments related to termination events that could have been required pursuant to these contingent features as of March 31, 2014 was approximately $422 million. Such accelerated settlement would not affect our consolidated results of operations.
	Derivatives Not Designated as Hedging Instruments:
	In connection with our trading activities, we use derivative financial instruments in our role as a financial intermediary and as both a manager and servicer of financial assets, in order to accommodate our clients' investment and risk management needs. In addition, we use derivative financial instruments for risk management purposes as economic hedges, which are not formally designated as accounting hedges, in order to contribute to our overall corporate earnings and liquidity. These activities are designed to generate trading services revenue and to manage volatility in our net interest revenue. The level of market risk that we assume is a function of our overall objectives and liquidity needs, our clients' requirements and market volatility.
	With respect to cross-border investing, our clients often enter into foreign exchange forward contracts to convert currency for international investments and to manage the currency risk in their international investment portfolios. As an active participant in the foreign exchange markets, we provide foreign exchange forward contracts and options in support of these client needs, and also act as a dealer in the currency markets. As part of our trading activities, we assume positions in both the foreign exchange and interest-rate markets by buying and selling cash instruments and using derivative financial instruments, including foreign exchange forward contracts, foreign exchange and interest-rate options and interest-rate swaps, interest-rate forward contracts, and interest-rate futures. In the aggregate, we seek to match positions closely with the objective of minimizing related currency and interest-rate risk.
	We offer products that provide book-value protection primarily to plan participants in stable value funds managed by non-affiliated investment managers of post-retirement defined contribution benefit plans, particularly 401(k) plans. We account for the associated contingencies, more fully described in note 7, individually as derivative financial instruments. These contracts are valued quarterly and unrealized losses, if any, are recorded in other expenses in our consolidated statement of income.
	Derivatives Designated as Hedging Instruments:
	In connection with our asset-and-liability management activities, we use derivative financial instruments to manage our interest-rate risk. Interest-rate risk, defined as the sensitivity of income or financial condition to variations in interest rates, is a significant non-trading market risk to which our assets and liabilities are exposed. We manage our interest-rate risk by identifying, quantifying and hedging our exposures, using fixed-rate portfolio securities and a variety of derivative financial instruments, most frequently interest-rate swaps and options (for example, interest-rate caps and floors). Interest-rate swap agreements alter the interest-rate characteristics of specific balance sheet assets or liabilities. When appropriate, forward-rate agreements, options on swaps, and exchange-traded futures and options are also used. Our hedging relationships are formally designated, and qualify for hedge accounting, as fair value or cash flow hedges.
	Fair value hedges
	Derivatives designated as fair value hedges are utilized to mitigate the risk of changes in the fair values of recognized assets and liabilities. Differences between the gains and losses on fair value hedges and the gains and losses on the asset or liability attributable to the hedged risk represent hedge ineffectiveness. We use interest-rate or foreign exchange contracts in this manner to manage our exposure to changes in the fair value of hedged items caused by changes in interest rates or foreign exchange rates.
	We have entered into interest-rate swap agreements to modify our interest revenue from certain available-for-sale investment securities from a fixed rate to a floating rate. The hedged securities had a weighted-average life of approximately 6.3 years as of March 31, 2014, compared to 6.5 years as of December 31, 2013. These securities are hedged with interest-rate swap contracts of similar maturity, repricing and fixed-rate coupons. The interest-rate swap contracts convert the interest revenue from a fixed rate to a floating rate indexed to LIBOR, thereby mitigating our exposure to fluctuations in the fair value of the securities attributable to changes in the benchmark interest rate.
	We have entered into interest-rate swap agreements to modify our interest expense on two senior notes and one subordinated note from fixed rates to floating rates. The senior notes mature in 2018 and 2023 and pay fixed interest at annual rates of 1.35% and 3.70%, respectively. The subordinated note matures in 2023 and pays fixed interest at a 3.10% annual rate. The senior and subordinated notes are hedged with interest-rate swap contracts with notional amounts, maturities and fixed-rate coupon terms that align with the hedged notes. The interest-rate swap contracts convert the fixed-rate coupons to floating rates indexed to LIBOR, thereby mitigating our exposure to fluctuations in the fair values of the senior and subordinated notes stemming from changes in the benchmark interest rates.
	We have entered into forward foreign exchange contracts to hedge the change in fair value attributable to foreign exchange movements in the funding of non-functional currency-denominated investment securities. These forward contracts convert the foreign currency risk to U.S. dollars, thereby mitigating our exposure to fluctuations in the fair value of the securities attributable to changes in foreign exchange rates. Generally, no ineffectiveness is recorded in earnings, since the notional amount of the hedging instruments is aligned with the carrying value of the hedged securities. The forward points on the hedging instruments are considered to be a hedging cost, and accordingly are excluded from the evaluation of hedge effectiveness and recorded in net interest revenue.
	Cash flow hedges
	Derivatives categorized as cash flow hedges are utilized to offset the variability of cash flows to be received from or paid on a floating-rate asset or liability. Ineffectiveness of cash flow hedges is defined as the extent to which the changes in fair value of the derivative exceed the variability of cash flows of the forecast transaction.
	We have entered into an interest-rate swap agreement to modify our interest revenue from an available-for-sale debt security from a floating rate to a fixed rate. The hedged security had a remaining life of approximately 7 months as of March 31, 2014, compared to approximately 10 months as of December 31, 2013. The security is hedged with an interest-rate swap contract of similar maturity, repricing and other characteristics. The interest-rate swap contract converts the interest revenue from a floating rate to a fixed rate, thereby mitigating our exposure to fluctuations in the cash flows of the security attributable to changes in the benchmark interest rate.
	We have entered into foreign exchange contracts to hedge the change in cash flows attributable to foreign exchange movements in the funding of non-functional currency-denominated investment securities. These foreign exchange contracts convert the foreign currency risk to U.S. dollars, thereby mitigating our exposure to fluctuations in the cash flows of the securities attributable to changes in foreign exchange rates. Generally, no ineffectiveness is recorded in earnings, since the critical terms of the hedging instruments and the hedged securities are aligned.
	For cash flow hedges, any changes in the fair value of the derivative financial instruments remain in AOCI, and are generally recorded in our consolidated statement of income in future periods when earnings are affected by the variability of the hedged cash flow.
	The following table presents the aggregate contractual, or notional, amounts of derivative financial instruments entered into in connection with our trading and asset-and-liability management activities as of the dates indicated:
	(In millions)	March 31,				December 31,
		2014				2013
	Derivatives not designated as hedging instruments:
	Interest-rate contracts:
	Swap agreements and forwards	$	878			$	1,023
	Options and caps purchased	20				27
	Options and caps written	20				27
	Futures	3,731				3,282
	Foreign exchange contracts:
	Forward, swap and spot	1,232,146				1,124,355
	Options purchased	1,484				1,666
	Options written	1,140				1,423
	Futures	14				—
	Credit derivative contracts:
	Credit swap agreements	141				141
	Total return swap agreements(1)	180				—
	Commodity and equity contracts:
	Commodity(1)	11,363				2
	Equity(1)	18				1
	Other:
	Stable value contracts	24,484				24,906
	Derivatives designated as hedging instruments:
	Interest-rate contracts:
	Swap agreements	5,222				5,221
	Foreign exchange contracts:
	Forward and swap	2,866				2,783
	(1) Primarily composed of positions held by a consolidated sponsored investment fund, more fully described in note 9.
	In connection with our asset-and-liability management activities, we have entered into interest-rate contracts designated as fair value and cash flow hedges to manage our interest-rate risk. The following table presents the aggregate notional amounts of these interest-rate contracts and the related assets or liabilities being hedged as of the dates indicated:
		March 31, 2014												December 31, 2013
	(In millions)	Fair				Cash				Total				Fair				Cash				Total
		Value				Flow								Value				Flow
		Hedges				Hedges								Hedges				Hedges
	Investment securities available for sale	$	2,589			$	133			$	2,722			$	2,589			$	132			$	2,721
	Long-term debt(1)	2,500				—				2,500				2,500				—				2,500
	Total	$	5,089			$	133			$	5,222			$	5,089			$	132			$	5,221
	(1) As of March 31, 2014, these fair value hedges increased the carrying value of long-term debt presented in our consolidated statement of condition by $3 million. As of December 31, 2013, these fair value hedges decreased the carrying value of long-term debt presented in our consolidated statement of condition by $35 million.
	The following table presents the contractual and weighted-average interest rates for long-term debt, which include the effects of the fair value hedges presented in the table above, for the periods indicated:
		Three Months Ended March 31,
	2014						2013
	Contractual			Rate Including			Contractual			Rate Including
	Rates			Impact of Hedges			Rates			Impact of Hedges
Long-term debt	3.39	%		2.6	%		3.77	%		3.03	%
The following tables present the fair value of derivative financial instruments, excluding the impact of master netting agreements, recorded in our
consolidated statement of condition as of the dates indicated. The impact of master netting agreements is disclosed in note 2.
	Asset Derivatives
	Balance Sheet		Fair Value
	Location
(In millions)			March 31, 2014				December 31, 2013
Derivatives not designated as hedging instruments:
Foreign exchange contracts	Other assets		$	8,012			$	11,552
Interest-rate contracts	Other assets		21				29
Other derivative contracts	Other assets		2				1
Total			$	8,035			$	11,582
Derivatives designated as hedging instruments:
Foreign exchange contracts	Other assets		$	306			$	359
Interest-rate contracts	Other assets		35				36
Total			$	341			$	395
	Liability Derivatives
	Balance Sheet		Fair Value
	Location
(In millions)			March 31, 2014				December 31, 2013
Derivatives not designated as hedging instruments:
Foreign exchange contracts	Other liabilities		$	7,771			$	11,428
Interest-rate contracts	Other liabilities		21				29
Other derivative contracts	Other liabilities		10				9
Total			$	7,802			$	11,466
Derivatives designated as hedging instruments:
Interest-rate contracts	Other liabilities		$	248			$	302
Foreign exchange contracts	Other liabilities		71				43
Total			$	319			$	345
The following tables present the impact of our use of derivative financial instruments on our consolidated statement of income for the periods indicated:
	Location of Gain (Loss) on		Amount of Gain (Loss) on Derivative Recognized in
	Derivative in Consolidated		Consolidated Statement
	Statement of Income		of Income
			Three Months Ended March 31,
(In millions)			2014				2013
Derivatives not designated as hedging instruments:
Foreign exchange contracts	Trading services revenue		$	134			$	145
Interest-rate contracts	Trading services revenue		—				1
Other derivative contracts	Processing fees and other revenue		(1		)		—
Total			$	133			$	146
	Location of Gain (Loss) on Derivative in Consolidated Statement of Income		Amount of Gain								Hedged Item in Fair Value Hedging Relationship		Location of Gain (Loss) on Hedged Item in Consolidated Statement of Income		Amount of Gain
			(Loss) on Derivative												(Loss) on Hedged
			Recognized in												Item Recognized in
			Consolidated												Consolidated
			Statement of Income												Statement of Income
(In millions)			Three Months Ended March 31,												Three Months Ended March 31,
Derivatives designated as fair value hedges:			2014				2013								2014				2013
Foreign exchange contracts	Processing fees and		$	42			$	4			Investment securities		Processing fees and		$	(42	)		$	(4	)
	other revenue												other revenue
Interest-rate contracts	Processing fees and		(12		)		1				Available-for-sale securities		Processing fees and		12				(2		)
	other revenue												other revenue
Interest-rate contracts	Processing fees and		49				(15		)		Long-term debt		Processing fees and		(45		)		16
	other revenue												other revenue
Total			$	79			$	(10	)						$	(75	)		$	10
Differences between the gains (losses) on the derivative and the gains (losses) on the hedged item,
excluding any amounts recorded in net interest revenue, represent hedge ineffectiveness.
	Amount of Gain								Location of Gain (Loss) Reclassified from OCI to Consolidated Statement of Income		Amount of Gain								Location of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income		Amount of Gain
	(Loss) on Derivative										(Loss) Reclassified										(Loss) on Derivative
	Recognized in Other										from OCI to										Recognized in
	Comprehensive										Consolidated										Consolidated
	Income										Statement of Income										Statement of Income
	Three Months Ended March 31,										Three Months Ended March 31,										Three Months Ended March 31,
(In millions)	2014				2013						2014				2013						2014		2013
Derivatives designated as cash flow hedges:
Interest-rate contracts	$	(1	)		$	12			Net interest revenue		$	(1	)		$	(1	)		Net interest revenue		$	1	$	1
Foreign exchange contracts	(12		)		105				Net interest revenue		—				—				Net interest revenue		1		3
Total	$	(13	)		$	117					$	(1	)		$	(1	)				$	2	$	4

Offsetting_Arrangements

Offsetting Arrangements	3 Months Ended
	Mar. 31, 2014
Offsetting [Abstract]	'
Offsetting Arrangements	'
	Offsetting Arrangements
	We manage credit and counterparty risk by entering into enforceable netting agreements and other collateral arrangements with counterparties to derivative contracts and secured financing transactions, including resale and repurchase agreements, and principal securities borrowing and lending agreements. These netting agreements mitigate our counterparty credit risk by providing for a single net settlement with a counterparty of all financial transactions covered by the agreement in an event of default as defined under such agreement. In limited cases, a netting agreement may also provide for the periodic netting of settlement payments with respect to multiple different transaction types in the normal course of business.
	Certain of our derivative contracts are executed under either standardized netting agreements or, for exchange-traded derivatives, the relevant contracts for a particular exchange which contain enforceable netting provisions. In certain cases, we may have cross-product netting arrangements which allow for netting and set-off of a variety of types of derivatives with a single counterparty. A derivative netting arrangement creates an enforceable right of set-off that becomes effective, and effects the realization or settlement of individual financial assets and liabilities, only following a specified event of default. Collateral requirements associated with our derivative contracts are determined after a review of the creditworthiness of each counterparty, and the requirements are monitored and adjusted daily, typically based on net exposure by counterparty. Collateral is generally in the form of cash or highly liquid U.S. government securities.
	In connection with secured financing transactions, we enter into netting agreements and other collateral arrangements with counterparties, which provide for the right to liquidate collateral in the event of default. Collateral is generally required in
	the form of cash, equity securities or fixed-income securities. Default events may include the failure to make payments or deliver securities timely, material adverse changes in financial condition or insolvency, the breach of minimum regulatory capital requirements, or loss of license, charter or other legal authorization necessary to perform under the contract.
	In order for an arrangement to be eligible for netting, we must have a reasonable basis to conclude that such netting arrangements are legally enforceable. The analysis of the legal enforceability of an arrangement differs by jurisdiction, depending on the laws of that jurisdiction. In many jurisdictions, specific legislation exists that provides for the enforceability in bankruptcy of close-out netting under a netting agreement, typically by way of specific exception from more general prohibitions on the exercise of creditor rights.
	When we have a basis to conclude that a legally enforceable netting arrangement exists between us and the derivative counterparty and the relevant transaction is the type of transaction that is recorded in our consolidated statement of condition, we offset derivative assets and liabilities, and the related collateral received and provided, in our consolidated statement of condition. We also offset assets and liabilities related to secured financing transactions with the same counterparty or clearinghouse which have the same maturity date and are settled in the normal course of business on a net basis.
	Collateral that we receive in the form of securities in connection with secured financing transactions and derivative contracts can be transferred or re-pledged as collateral in many instances to enter into repurchase agreements or securities finance or derivative transactions. The securities collateral received in connection with our securities finance activities is recorded at fair value in other assets in our consolidated statement of condition, with a related liability to return the collateral, if we have the right to transfer or re-pledge the collateral. As of March 31, 2014 and December 31, 2013, the fair value of securities received as collateral where we are permitted to transfer or re-pledge the securities totaled $4.60 billion and $5.64 billion, respectively, and the fair value of the portion that had been transferred or re-pledged as of the same date was $1.53 billion and $1.77 billion, respectively.
	The following tables present information about the offsetting of assets related to derivative contracts and secured financing transactions, as of the dates indicated:
	Assets:	31-Mar-14								31-Dec-13
	(In millions)	Gross Amounts of Recognized Assets(1)		Gross Amounts Offset in Statement of Condition(2)			Net Amounts of Assets Presented in Statement of Condition			Gross Amounts of Recognized Assets(1)		Gross Amounts Offset in Statement of Condition(2)			Net Amounts of Assets Presented in Statement of Condition
	Derivatives:
	Interest-rate contracts	$	56	$	(45	)	$	11		$	65	$	(59	)	$	6
	Foreign exchange contracts	8,318		(3,489		)	4,829			11,911		(4,514		)	7,397
	Other derivative contracts	2		(1		)	1			1		—			1
	Cash collateral netting	—		(1,372		)	(1,372		)	—		(1,928		)	(1,928		)
	Total derivatives	$	8,376	$	(4,907	)	$	3,469		$	11,977	$	(6,501	)	$	5,476
	Other financial instruments:
	Resale agreements and securities borrowing(3)	$	47,715	$	(30,307	)	$	17,408		$	48,221	$	(30,700	)	$	17,521
	Total derivatives and other financial instruments	$	56,091	$	(35,214	)	$	20,877		$	60,198	$	(37,201	)	$	22,997
	(1) Amounts include all transactions regardless of whether or not they are subject to an enforceable netting arrangement.
	(2) Amounts subject to netting arrangements which have been determined to be legally enforceable.
	(3) Included in the $17,408 million as of March 31, 2014 was $6,087 million of resale agreements and $11,321 million of collateral provided related to securities borrowing. Included in the $17,521 million as of December 31, 2013 was $6,230 million of resale agreements and $11,291 million of collateral provided related to securities borrowing. Resale agreements and collateral provided related to securities borrowing were recorded in securities purchased under resale agreements and other assets, respectively, in our consolidated statement of condition. Refer to note 7 for additional information with respect to principal securities finance transactions.
		31-Mar-14										31-Dec-13
				Gross Amounts Not Offset in Statement of Condition(1)											Gross Amounts Not Offset in Statement of Condition(1)
	(In millions)	Net Amount of Assets Presented in Statement of Condition		Counterparty Netting			Collateral Received			Net Amount(2)		Net Amount of Assets Presented in Statement of Condition			Counterparty Netting			Collateral Received			Net Amount(2)
	Derivatives	$	3,469	$	—		$	(187	)	$	3,282	$	5,476		$	—		$	(181	)	$	5,295
	Resale agreements and securities borrowing	17,408		(113		)	(15,099		)	2,196		17,521			(131		)	(14,983		)	2,407
	Total	$	20,877	$	(113	)	$	(15,286	)	$	5,478	$	22,997		$	(131	)	$	(15,164	)	$	7,702
	(1) Amounts subject to netting arrangements which have been determined to be legally enforceable.
	(2) Includes amounts secured by collateral not determined to be subject to enforceable netting arrangements.
	The following tables present information about the offsetting of liabilities related to derivative contracts and secured financing transactions, as of the dates indicated:
	Liabilities:	31-Mar-14								31-Dec-13
	(In millions)	Gross Amounts of Recognized Liabilities(1)		Gross Amounts Offset in Statement of Condition(2)			Net Amounts of Liabilities Presented in Statement of Condition			Gross Amounts of Recognized Liabilities(1)		Gross Amounts Offset in Statement of Condition(2)			Net Amounts of Liabilities Presented in Statement of Condition
	Derivatives:
	Interest-rate contracts	$	269	$	(45	)	$	224		$	331	$	(59	)	$	272
	Foreign exchange contracts	7,842		(3,489		)	4,353			11,471		(4,514		)	6,957
	Other derivative contracts	10		(1		)	9			9		—			9
	Cash collateral netting	—		(274		)	(274		)	—		(979		)	(979		)
	Total derivatives	$	8,121	$	(3,809	)	$	4,312		$	11,811	$	(5,552	)	$	6,259
	Other financial instruments:
	Repurchase agreements and securities lending(3)	$	45,545	$	(30,307	)	$	15,238		$	45,273	$	(30,700	)	$	14,573
	Total derivatives and other financial instruments	$	53,666	$	(34,116	)	$	19,550		$	57,084	$	(36,252	)	$	20,832
	(1) Amounts include all transactions regardless of whether or not they are subject to an enforceable netting arrangement.
	(2) Amounts subject to netting arrangements which have been determined to be legally enforceable.
	(3) Included in the $15,238 million as of March 31, 2014 was $8,953 million of repurchase agreements and $6,285 million of collateral received related to securities lending. Included in the $14,573 million as of December 31, 2013 was $7,953 million of repurchase agreements and $6,620 million of collateral received related to securities lending. Repurchase agreements and collateral received related to securities lending were recorded in securities sold under repurchase agreements and accrued expenses and other liabilities, respectively, in our consolidated statement of condition. Refer to note 7 for additional information with respect to principal securities finance transactions.
		31-Mar-14										31-Dec-13
				Gross Amounts Not Offset in Statement of Condition(1)											Gross Amounts Not Offset in Statement of Condition(1)
	(In millions)	Net Amount of Liabilities Presented in Statement of Condition		Counterparty Netting			Collateral Provided			Net Amount(2)		Net Amount of Liabilities Presented in Statement of Condition			Counterparty Netting			Collateral Provided			Net Amount(2)
	Derivatives	$	4,312	$	—		$	—		$	4,312	$	6,259		$	—		$	(6	)	$	6,253
	Repurchase agreements and securities lending	15,238		(113		)	(13,015		)	2,110		14,573			(131		)	(13,036		)	1,406
	Total	$	19,550	$	(113	)	$	(13,015	)	$	6,422	$	20,832		$	(131	)	$	(13,042	)	$	7,659
	(1) Amounts subject to netting arrangements which have been determined to be legally enforceable.
	(2) Includes amounts secured by collateral not determined to be subject to enforceable netting arrangements.

Net_Interest_Revenue

Net Interest Revenue	3 Months Ended
	Mar. 31, 2014
Net Interest Revenue [Abstract]	'
Net Interest Revenue	'
	Net Interest Revenue
	The following table presents the components of interest revenue and interest expense, and related net interest revenue, for the periods indicated:
		Three Months Ended March 31,
	(In millions)	2014		2013
	Interest revenue:
	Deposits with banks	$	34	$	31
	Investment securities:
	U.S. Treasury and federal agencies	163		194
	State and political subdivisions	71		51
	Other investments	319		341
	Securities purchased under resale agreements	9		13
	Loans and leases	58		56
	Other interest-earning assets	1		1
	Total interest revenue	655		687
	Interest expense:
	Deposits	15		34
	Short-term borrowings	15		16
	Long-term debt	63		56
	Other interest-bearing liabilities	7		5
	Total interest expense	100		111
	Net interest revenue	$	555	$	576

Expenses

Expenses	3 Months Ended
	Mar. 31, 2014
Other Expenses [Abstract]	'
Expenses	'
	Expenses
	Severance Costs:
	In the three months ended March 31, 2014, we recorded $72 million of severance costs. These severance costs were the result of staff reductions associated with the realignment of our cost base, and were recorded in compensation and employee benefits expenses in our consolidated statement of income.
	Acquisition and Restructuring Costs:
	The following table presents net acquisition and restructuring costs recorded in the periods indicated:
		Three Months Ended March 31,
	(In millions)	2014			2013
	Acquisition costs	$	21		$	15
	Restructuring charges, net	12			(1		)
	Total acquisition and restructuring costs	$	33		$	14
	Acquisition Costs
	Acquisition costs recorded in the three months ended March 31, 2014 and 2013 were related to previously disclosed acquisitions.
	Restructuring Charges
	Information with respect to our Business Operations and Information Technology Transformation program and our 2012 expense control measures, including charges, employee reductions and aggregate activity in the related accruals, is provided in the two sections that follow.
	Business Operations and Information Technology Transformation Program
	In November 2010, we announced a global multi-year Business Operations and Information Technology Transformation program. The program includes operational, information technology and targeted cost initiatives, including plans related to reductions in both staff and occupancy costs. To date, we have recorded aggregate restructuring charges of $390 million in our consolidated statement of income, composed of $156 million in 2010, $133 million in 2011, $67 million in 2012, $25 million in 2013 and $9 million in the three months ended March 31, 2014.
	The charges related to the program included costs related to severance, benefits and outplacement services, as well as costs which resulted from actions taken to reduce our occupancy costs through the consolidation of leases and properties. The charges also included costs related to information technology, including transition fees associated with the expansion of our use of third-party service providers associated with components of our information technology infrastructure and application maintenance and support.
	In 2010, in connection with the program, we initiated the involuntary termination of 1,400 employees, or approximately 5% of our global workforce, which we completed by the end of 2011. In addition, in connection with our announcement in 2011 of the expansion of our use of third-party service providers associated with our information technology infrastructure and application maintenance and support, as well as the continued execution of the business operations transformation component of the program, we identified 1,436 additional involuntary terminations. As of March 31, 2014, we eliminated 1,375 of these positions.
	Expense Control Measures
	In December 2012, in connection with expense control measures designed to better align our expenses to our business strategy and related outlook for 2013, we identified additional targeted staff reductions. As a result of these actions, we have recorded aggregate pre-tax restructuring charges of $133 million in 2012, $3 million in 2013 and $3 million in the three months ended March 31, 2014 in our consolidated statement of income. Employee-related costs included severance, benefits and outplacement services. Costs for asset and other write-offs were primarily related to contract terminations. We originally identified involuntary terminations of 960 employees (630 positions after replacements).  As of March 31, 2014, we substantially completed these reductions.
	Aggregate Restructuring-Related Accrual Activity
	The following table presents aggregate activity associated with accruals that resulted from the charges associated with the Business Operations and Information Technology Transformation program and expense control measures:
	(In millions)	Employee-			Real Estate Consolidation			Asset and Other Write-Offs			Total
		Related
		Costs
	Balance as of December 31, 2013	$	50		$	49		$	7		$	106
	Additional accruals for Business Operations and Information Technology Transformation program	6			3			—			9
	Additional accruals for 2012 expense control measures	—			—			3			3
	Payments and adjustments	(17		)	(12		)	(2		)	(31		)
	Balance as of March 31, 2014	$	39		$	40		$	8		$	87

Earnings_Per_Common_Share

Earnings Per Common Share	3 Months Ended
	Mar. 31, 2014
Earnings Per Share [Abstract]	'
Earnings Per Common Share	'
	Earnings Per Common Share
	The following table presents the computation of basic and diluted earnings per common share for the periods indicated:
		Three Months Ended March 31,
	(Dollars in millions, except per share amounts)	2014			2013
	Net income	$	363		$	464
	Less:
	Preferred stock dividends	(6		)	(7		)
	Dividends and undistributed earnings allocated to participating securities(1)	(1		)	(2		)
	Net income available to common shareholders	$	356		$	455
	Average common shares outstanding (in thousands):
	Basic average common shares	430,621			454,315
	Effect of dilutive securities: common stock options and common stock awards	8,194			8,436
	Diluted average common shares	438,815			462,751
	Anti-dilutive securities(2)	1,504			2,488
	Earnings per Common Share:
	Basic	$	0.83		$	1
	Diluted(3)	0.81			0.98
	(1) Represented the portion of net income available to common equity allocated to participating securities, composed of fully vested deferred director stock and unvested restricted stock that contain non-forfeitable rights to dividends during the vesting period on a basis equivalent to dividends paid to common shareholders.
	(2) Represented common stock options and other equity-based awards outstanding but not included in the computation of diluted average shares, because their effect was anti-dilutive.
	(3) Calculations reflect allocation of earnings to participating securities using the two-class method, as this computation is more dilutive than the treasury stock method.

Line_of_Business_Information

Line of Business Information	3 Months Ended
	Mar. 31, 2014
Segment Reporting [Abstract]	'
Line of Business Information	'
	Line of Business Information
	We have two lines of business: Investment Servicing and Investment Management. Given our services and management organization, the results of operations for these lines of business are not necessarily comparable with those of other companies, including companies in the financial services industry. Information about our two lines of business, as well as revenues, expenses and capital allocation methodologies associated with these lines of business, is provided in note 25 to the consolidated financial statements included in our 2013 Form 10-K.
	The following table provides a summary of our line-of-business results for the periods indicated. The “Other” column for three months ended March 31, 2014 included $72 million of severance costs associated with staff reductions; $33 million of acquisition and restructuring costs; and $6 million of net provisions for litigation exposure and other costs. The “Other” column for three months ended March 31, 2013 included $14 million of net acquisition and restructuring costs. The amounts in the “Other” columns were not allocated to State Street's business lines. Results for the three months ended March 31, 2013 reflect reclassifications, for comparative purposes, related to management changes in methodologies associated with allocations of revenue and expenses reflected in line-of-business results for 2014.
		Three Months Ended March 31,
		Investment						Investment						Other						Total
		Servicing						Management
		2014			2013			2014			2013			2014			2013			2014			2013
	(Dollars in millions,
	except where otherwise noted)
	Fee revenue:
	Servicing fees	$	1,238		$	1,175		$	—		$	—		$	—		$	—		$	1,238		$	1,175
	Management fees	—			—			292			263			—			—			292			263
	Trading services	227			257			12			24			—			—			239			281
	Securities finance	85			78			—			—			—			—			85			78
	Processing fees and other	69			55			1			5			—			—			70			60
	Total fee revenue	1,619			1,565			305			292			—			—			1,924			1,857
	Net interest revenue	538			557			17			19			—			—			555			576
	Gains (losses) related to investment securities, net	6			2			—			—			—			—			6			2
	Total revenue	2,163			2,124			322			311			—			—			2,485			2,435
	Provision for loan losses	2			—			—			—			—			—			2			—
	Total expenses	1,673			1,590			244			222			111			14			2,028			1,826
	Income before income tax expense	$	488		$	534		$	78		$	89		$	(111	)	$	(14	)	$	455		$	609
	Pre-tax margin	23		%	25		%	24		%	29		%							18		%	25		%
	Average assets (in billions)	$	212.2		$	204.4		$	3.4		$	3.9								$	215.6		$	208.3

NonUS_Activities

Non-U.S. Activities	3 Months Ended
	Mar. 31, 2014
Segments, Geographical Areas [Abstract]	'
Non-U.S. Activities	'
	Non-U.S. Activities
	We generally define our non-U.S. activities as those revenue-producing business activities that arise from clients domiciled outside the U.S. Due to the integrated nature of our business, precise segregation of our U.S. and non-U.S. activities is not possible. Subjective estimates and other judgments are applied to quantify the financial results and assets related to our non-U.S. activities, including our application of funds transfer pricing, our asset-and-liability management policies and our allocation of certain indirect corporate expenses. Interest expense allocations are based on our internal funds transfer pricing methodology.
	The following table presents our non-U.S. financial results for the periods indicated.
		Three Months Ended March 31,
	(In millions)	2014		2013
	Total fee revenue	$	788	$	765
	Net interest revenue	325		273
	Gains (losses) related to investment securities, net	6		(3		)
	Total revenue	1,119		1,035
	Expenses	839		753
	Income before income taxes	280		282
	Income tax expense	65		69
	Net income	$	215	$	213
	The following table presents the significant components of our non-U.S. assets as of the dates indicated, based on the domicile of the underlying counterparties:
	(In millions)	March 31, 2014		December 31, 2013
	Interest-bearing deposits with banks	$	10,281	$	9,584
	Investment securities	31,790		31,522
	Other assets	17,552		16,778
	Total non-U.S. assets	$	59,623	$	57,884

Basis_of_Presentation_Policies

Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
Recent Accounting Developments	'
	Recent Accounting Developments:
	In April 2014, the FASB issued an amendment to GAAP that revises the criteria for the treatment and disclosure of discontinued operations. The amendment allows entities to have significant continuing involvement and continuing cash flows with the discontinued operation, but requires additional disclosure for discontinued operations and disclosure for disposals deemed to be material that do not meet the definition of a discontinued operation. The presentation and disclosure requirements are effective, for State Street, beginning on January 1, 2015, and are required to be applied prospectively to discontinued operations occurring after that date.
	In January 2014, the FASB issued an amendment to GAAP that allows an investor in an affordable housing project, if the project meets certain defined conditions, to amortize the cost of their investment in proportion to the tax credits and other tax benefits they receive, and reflect it as part of income tax expense rather than as revenue from operations. The amendment is effective, for State Street, for interim and annual periods beginning after December 15, 2014, with early adoption permitted, and must be applied retrospectively. At this time, we have not chosen to early-adopt the amendment. Our adoption of the amendment is not expected to have a material effect on our consolidated financial statements.
Asset-Backed Securitization Trusts	'
	We invest in various forms of asset-backed securities, which we carry in our investment securities portfolio. These asset-backed securities meet the GAAP definition of asset securitization entities, which are considered to be variable interest entities, or VIEs, as defined by GAAP. We are not considered to be the primary beneficiary of these VIEs, as defined by GAAP, since we do not have control over their activities. Additional information about our asset-backed securities is provided in note 3.
Tax-Exempt Investment Program	'
	Tax-Exempt Investment Program:
	In the normal course of our business, we structure and sell certificated interests in pools of tax-exempt investment-grade assets, principally to our mutual fund clients. We structure these pools as partnership trusts, and the assets and liabilities of the trusts are recorded in our consolidated statement of condition as investment securities available for sale and other short-term borrowings. We may also provide liquidity and re-marketing services to the trusts. As of March 31, 2014 and December 31, 2013, we carried investment securities available for sale, composed of securities related to state and political subdivisions, with a fair value of $2.33 billion as of each date, and other short-term borrowings of $1.93 billion and $1.95 billion, respectively, in our consolidated statement of condition in connection with these trusts.
	We transfer assets to the trusts from our investment securities portfolio at adjusted book value, and the trusts finance the acquisition of these assets by selling certificated interests issued by the trusts to third-party investors and to State Street as residual holder. These transfers do not meet the de-recognition criteria defined by GAAP, and therefore, are recorded in our consolidated financial statements. The trusts had a weighted-average life of approximately 6.3 years as of March 31, 2014, compared to approximately 6.5 years as of December 31, 2013.
	Under separate legal agreements, we provide standby bond-purchase agreements to these trusts and, with respect to certain securities, letters of credit. Our commitments to the trusts under these standby bond-purchase agreements and letters of credit totaled $1.96 billion and $684 million, respectively, as of March 31, 2014, none of which was utilized as of that date. In the event that our obligations under these agreements are triggered, no material impact to our consolidated results of operations or financial condition is expected to occur, because the securities are already recorded at fair value in our consolidated statement of condition.

Fair_Value_Tables

Fair Value (Tables)	3 Months Ended
	Mar. 31, 2014
Fair Value Disclosures [Abstract]	'
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	'
	The following tables present information with respect to our financial assets and liabilities carried at fair value in our consolidated statement of condition on a recurring basis as of the dates indicated. No transfers of financial assets or liabilities between levels 1 and 2 occurred during the three months ended March 31, 2014 or the year ended December 31, 2013.
		Fair-Value Measurements on a Recurring Basis
		as of March 31, 2014
	(In millions)	Quoted Market			Pricing Methods			Pricing Methods				Impact of Netting(1)			Total Net
		Prices in Active			with Significant			with Significant							Carrying Value
		Markets			Observable			Unobservable							in Consolidated
		(Level 1)			Market Inputs			Market Inputs							Statement of
					(Level 2)			(Level 3)							Condition
	Assets:
	Trading account assets:
	U.S. government securities	$	20		$	—		$	—						$	20
	Non-U.S. government securities	401			—			—							401
	Other	60			408			—							468
	Total trading account assets	481			408			—							889
	Investment securities available for sale:
	U.S. Treasury and federal agencies:
	Direct obligations	1,280			683			—							1,963
	Mortgage-backed securities	—			22,992			100							23,092
	Asset-backed securities:
	Student loans	—			13,947			333							14,280
	Credit cards	—			7,237			—							7,237
	Sub-prime	—			1,155			—							1,155
	Other	—			576			4,304							4,880
	Total asset-backed securities	—			22,915			4,637							27,552
	Non-U.S. debt securities:
	Mortgage-backed securities	—			11,196			—							11,196
	Asset-backed securities	—			4,382			612							4,994
	Government securities	—			3,692			—							3,692
	Other	—			4,522			462							4,984
	Total non-U.S. debt securities	—			23,792			1,074							24,866
	State and political subdivisions	—			10,402			42							10,444
	Collateralized mortgage obligations	—			5,060			202							5,262
	Other U.S. debt securities	—			4,938			8							4,946
	U.S. equity securities	—			36			—							36
	Non-U.S. equity securities	—			1			—							1
	U.S. money-market mutual funds	—			993			—							993
	Non-U.S. money-market mutual funds	—			7			—							7
	Total investment securities available for sale	1,280			91,819			6,063							99,162
	Other assets:
	Derivative instruments:
	Foreign exchange contracts	—			8,312			6				$	(4,850	)	3,468
	Interest-rate contracts	—			56			—				(56		)	—
	Other derivative contracts	—			2			—				(1		)	1
	Total derivative instruments	—			8,370			6				(4,907		)	3,469
	Other	100			—			—				—			100
	Total assets carried at fair value	$	1,861		$	100,597		$	6,069			$	(4,907	)	$	103,620
	Liabilities:
	Accrued expenses and other liabilities:
	Derivative instruments:
	Foreign exchange contracts	$	—		$	7,834		$	8			$	(3,752	)	$	4,090
	Interest-rate contracts	—			269			—				(56		)	213
	Other derivative contracts	—			1			9				(1		)	9
	Total derivative instruments	—			8,104			17				(3,809		)	4,312
	Other	100			—			—				—			100
	Total liabilities carried at fair value	$	100		$	8,104		$	17			$	(3,809	)	$	4,412
	(1) Represents counterparty netting against level-2 financial assets and liabilities, where a legally enforceable master netting agreement exists between State Street and the counterparty. Netting also reflects asset and liability reductions of $1.37 billion and $274 million, respectively, for cash collateral received from and provided to derivative counterparties.
		Fair-Value Measurements on a Recurring Basis
		as of December 31, 2013
	(In millions)	Quoted Market			Pricing Methods			Pricing Methods				Impact of Netting(1)			Total Net
		Prices in Active			with Significant			with Significant							Carrying Value
		Markets			Observable			Unobservable							in Consolidated
		(Level 1)			Market Inputs			Market Inputs							Statement of
					(Level 2)			(Level 3)							Condition
Assets:
Trading account assets:
U.S. government securities	$	20		$	—		$	—						$	20
Non-U.S. government securities	399			—			—							399
Other	67			357			—							424
Total trading account assets	486			357			—							843
Investment securities available for sale:
U.S. Treasury and federal agencies:
Direct obligations	—			709			—							709
Mortgage-backed securities	—			22,847			716							23,563
Asset-backed securities:
Student loans	—			14,119			423							14,542
Credit cards	—			8,186			24							8,210
Sub-prime	—			1,203			—							1,203
Other	—			532			4,532							5,064
Total asset-backed securities	—			24,040			4,979							29,019
Non-U.S. debt securities:
Mortgage-backed securities	—			10,654			375							11,029
Asset-backed securities	—			4,592			798							5,390
Government securities	—			3,761			—							3,761
Other	—			4,263			464							4,727
Total non-U.S. debt securities	—			23,270			1,637							24,907
State and political subdivisions	—			10,220			43							10,263
Collateralized mortgage obligations	—			5,107			162							5,269
Other U.S. debt securities	—			4,972			8							4,980
U.S. equity securities	—			34			—							34
Non-U.S. equity securities	—			1			—							1
U.S. money-market mutual funds	—			422			—							422
Non-U.S. money-market mutual funds	—			7			—							7
Total investment securities available for sale	—			91,629			7,545							99,174
Other assets:
Derivatives instruments:
Foreign exchange contracts	—			11,892			19				$	(6,442	)	5,469
Interest-rate contracts	—			65			—				(59		)	6
Other derivative contracts	—			1			—				—			1
Total derivative instruments	—			11,958			19				(6,501		)	5,476
Other	97			—			—				—			97
Total assets carried at fair value	$	583		$	103,944		$	7,564			$	(6,501	)	$	105,590
Liabilities:
Accrued expenses and other liabilities:
Derivative instruments:
Foreign exchange contracts	$	—		$	11,454		$	17			$	(5,458	)	$	6,013
Interest-rate contracts	—			331			—				(94		)	237
Other derivative contracts	—			—			9				—			9
Total derivative instruments	—			11,785			26				(5,552		)	6,259
Other	97			—			—				—			97
Total liabilities carried at fair value	$	97		$	11,785		$	26			$	(5,552	)	$	6,356
(1) Represents counterparty netting against level-2 financial assets and liabilities, where a legally enforceable master netting agreement exists between State Street and the counterparty. Netting also reflects asset and liability reductions of $1.93 billion and $979 million, respectively, for cash collateral received from and provided to derivative counterparties.
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation	'
		Fair-Value Measurements Using Significant Unobservable Inputs
		Three Months Ended March 31, 2014
		Fair			Total Realized and							Purchases			Issuances			Sales			Settlements			Transfers		Transfers			Fair		Change in
		Value as of			Unrealized Gains (Losses)																			into		out of			Value as of		Unrealized
		December 31,																						Level 3		Level 3			March 31,		Gains
		2013																											2014		(Losses)
																															Related to
																															Financial
																															Instruments
																															Held as of
																															March 31,
	(In millions)				Recorded			Recorded																							2014
					in			in Other
					Revenue			Comprehensive
								Income
	Assets:
	Investment securities available for sale:
	U.S. Treasury and federal agencies, mortgage-backed securities	$	716		$	—		$	—			$	—		$	—		$	—		$	(5	)	$	—	$	(611	)	$	100
	Asset-backed securities:
	Student loans	423			1			1				—			—			—			(13		)	—		(79		)	333
	Credit cards	24			—			—				—			—			—			(24		)	—		—			—
	Other	4,532			15			(4		)		6			—			—			(245		)	—		—			4,304
	Total asset-backed securities	4,979			16			(3		)		6			—			—			(282		)	—		(79		)	4,637
	Non-U.S. debt securities:
	Mortgage-backed securities	375			—			—				—			—			—			—			—		(375		)	—
	Asset-backed securities	798			2			(1		)		—			—			—			(63		)	—		(124		)	612
	Other	464			—			(1		)		—			—			(1		)	—			—		—			462
	Total non-U.S. debt securities	1,637			2			(2		)		—			—			(1		)	(63		)	—		(499		)	1,074
	State and political subdivisions	43			—			—				—			—			—			(1		)	—		—			42
	Collateralized mortgage obligations	162			—			—				80			—			(6		)	(6		)	—		(28		)	202
	Other U.S. debt securities	8			—			—				—			—			—			—			—		—			8
	Total investment securities available for sale	7,545			18			(5		)		86			—			(7		)	(357		)	—		(1,217		)	6,063
	Other assets:
	Derivative instruments:
	Derivative instruments, Foreign exchange contracts	19			(11		)	—				7			—			—			(9		)	—		—			6		$	(7	)
	Total derivative instruments	19			(11		)	—				7			—			—			(9		)	—		—			6		(7		)
	Total assets carried at fair value	$	7,564		$	7		$	(5	)		$	93		$	—		$	(7	)	$	(366	)	$	—	$	(1,217	)	$	6,069	$	(7	)
		Fair-Value Measurements Using Significant Unobservable Inputs
		Three Months Ended March 31, 2013
		Fair			Total Realized and							Purchases			Issuances			Sales			Settlements			Transfers		Transfers			Fair		Change in
		Value as of December 31,			Unrealized Gains (Losses)																			into		out of			Value as of		Unrealized
		2012																						Level 3		Level 3			March 31,		Gains
																													2013		(Losses)
																															Related to
																															Financial
																															Instruments
																															Held as of
																															31-Mar
	(In millions)				Recorded			Recorded																							2013
					in			in Other
					Revenue			Comprehensive
								Income
	Assets:
	Investment securities available for sale:
	U.S. Treasury and federal agencies:
	Mortgage-backed securities	$	825		$	—		$	—			$	—		$	—		$	—		$	(27	)	$	—	$	—		$	798
	Asset-backed securities:
	Student loans	588			—			7				—			—			(26		)	(8		)	—		(100		)	461
	Credit cards	67			—			—				—			—			—			(43		)	—		—			24
	Other	3,994			13			21				180			—			(10		)	(326		)	—		—			3,872
	Total asset-backed securities	4,649			13			28				180			—			(36		)	(377		)	—		(100		)	4,357
	Non-U.S. debt securities:
	Mortgage-backed securities	555			—			—				—			—			—			(17		)	—		(207		)	331
Asset-backed securities	524			2			3				51			—			—			(33		)	—		(77		)	470
Other	140			—			—				179			—			—			(3		)	—		(40		)	276
Total non-U.S. debt securities	1,219			2			3				230			—			—			(53		)	—		(324		)	1,077
State and political subdivisions	48			—			1				—			—			—			(2		)	—		—			47
Collateralized mortgage obligations	117			—			—				—			—			—			(9		)	—		—			108
Other U.S. debt securities	9			—			—				—			—			—			—			—		—			9
Total investment securities available for sale	6,867			15			32				410			—			(36		)	(468		)	—		(424		)	6,396
Other assets:
Derivative instruments:
Foreign exchange contracts	113			95			—				53			—			—			(89		)	—		—			172		$	53
Total derivative instruments	113			95			—				53			—			—			(89		)	—		—			172		53
Total assets carried at fair value	$	6,980		$	110		$	32			$	463		$	—		$	(36	)	$	(557	)	$	—	$	(424	)	$	6,568	$	53
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation	'
		Fair-Value Measurements Using Significant Unobservable Inputs
		Three Months Ended March 31, 2014
		Fair			Total Realized and							Purchases			Issuances			Sales			Settlements			Transfers		Transfers			Fair		Change in
		Value as of			Unrealized (Gains) Losses																			into		out of			Value as of		Unrealized
		December 31,																						Level 3		Level 3			March 31,		(Gains)
		2013																											2014		Losses
																															Related to
																															Financial
																															Instruments
																															Held as of
																															March 31,
	(In millions)				Recorded			Recorded																							2014
					in			in Other
					Revenue			Comprehensive
								Income
	Liabilities:
	Accrued expenses and other liabilities:
	Derivative instruments:
	Foreign exchange contracts	$	17		$	(10	)	$	—			$	—		$	7		$	—		$	(6	)	$	—	$	—		$	8	$	(5	)
	Other	9			—			—				—			—			—			—			—		—			9		—
	Total derivative instruments	26			(10		)	—				—			7			—			(6		)	—		—			17		(5		)
	Total liabilities carried at fair value	$	26		$	(10	)	$	—			$	—		$	7		$	—		$	(6	)	$	—	$	—		$	17	$	(5	)
		Fair-Value Measurements Using Significant Unobservable Inputs
		Three Months Ended March 31, 2013
		Fair			Total Realized and							Purchases			Issuances			Sales			Settlements			Transfers		Transfers			Fair		Change in
		Value as of December 31,			Unrealized (Gains) Losses																			into		out of			Value as of		Unrealized
		2012																						Level 3		Level 3			March 31,		(Gains)
																													2013		Losses
																															Related to
																															Financial
																															Instruments
																															Held as of
																															March 31,
	(In millions)				Recorded			Recorded																							2013
					in			in Other
					Revenue			Comprehensive
								Income
	Liabilities:
	Accrued expenses and other liabilities:
	Derivative instruments:
	Foreign exchange contracts	$	106		$	61		$	—			$	—		$	50		$	—		$	(64	)	$	—	$	—		$	153	$	39
	Other	9			—			—				—			—			—			—			—		—			9		—
	Total derivative instruments	115			61			—				—			50			—			(64		)	—		—			162		39
	Total liabilities carried at fair value	$	115		$	61		$	—			$	—		$	50		$	—		$	(64	)	$	—	$	—		$	162	$	39
Level 3 Total Realized And Unrealized Gains And Losses Recorded In Revenue	'
	The following table presents total realized and unrealized gains and losses for the periods indicated that were recorded in revenue for our level-3 financial assets and liabilities:
		Three Months Ended March 31,
		Total Realized and						Change in
		Unrealized Gains						Unrealized Gains
		(Losses) Recorded						(Losses) Related to
		in Revenue						Financial
								Instruments Held as of March 31,
	(In millions)	2014			2013			2014				2013
	Fee revenue:
	Trading services	$	(1	)	$	34		$	(2	)		$	14
	Total fee revenue	(1		)	34			(2		)		14
	Net interest revenue	18			15			—				—
	Total revenue	$	17		$	49		$	(2	)		$	14
Fair Value Inputs, Assets and Liabilities, Quantitative Information	'
	The following table presents quantitative information, as of the dates indicated, about the valuation techniques and significant unobservable inputs used in the valuation of our level-3 financial assets and liabilities measured at fair value on a recurring basis for which we use internally-developed pricing models. The significant unobservable inputs for our level-3 financial assets and liabilities whose fair value is measured using pricing information from non-binding broker or dealer quotes are not included in the table, as the specific inputs applied are not provided by the broker/dealer.
			Quantitative Information about Level-3 Fair-Value Measurements
			Fair Value										Weighted-Average
	(Dollars in millions)		As of March 31, 2014			As of December 31, 2013			Valuation Technique		Significant		As of March 31, 2014		As of December 31, 2013
											Unobservable Input
	Significant unobservable inputs readily available to State Street:
	Assets:
	Asset-backed securities, student loans		$	14		$	13		Discounted cash flows		Credit spread		2.9	%	3.5	%
	Asset-backed securities, credit cards		—			24			Discounted cash flows		Credit spread		—		2
	Asset-backed securities, other		87			92			Discounted cash flows		Credit spread		1.3		1.5
	State and political subdivisions		42			43			Discounted cash flows		Credit spread		1.7		1.7
	Derivative instruments, foreign exchange contracts		6			19			Option model		Volatility		8		11.4
	Total		$	149		$	191
	Liabilities:
	Derivative instruments, foreign exchange contracts		$	8		$	17		Option model		Volatility		8		11.2
	Derivative instruments, other(1)		9			9			Discounted cash flows		Participant redemptions		7.4		7.5
	Total		$	17		$	26
	(1) Relates to stable value wrap contracts; refer to the sensitivity discussion following the tables presented below, and to note 7.
Schedule of Availability of Significant Unobservable Inputs by Balance Sheet Classification	'
	The following tables present information with respect to the composition of our level-3 financial assets and
	liabilities, by availability of significant unobservable inputs, as of the dates indicated:
	31-Mar-14		Significant Unobservable Inputs Readily Available to State Street(1)			Significant Unobservable Inputs Not Developed by State Street and Not Readily Available(2)			Total Assets and Liabilities with Significant Unobservable Inputs
	(In millions)
	Assets:
	U.S. Treasury and federal agencies, mortgage-backed securities		$	—		$	100		$	100
	Asset-backed securities, student loans		14			319			333
	Asset-backed securities, other		87			4,217			4,304
	Non-U.S. debt securities, asset-backed securities		—			612			612
	Non-U.S. debt securities, other		—			462			462
	State and political subdivisions		42			—			42
	Collateralized mortgage obligations		—			202			202
	Other U.S.debt securities		—			8			8
	Derivative instruments, foreign exchange contracts		6			—			6
	Total		$	149		$	5,920		$	6,069
	Liabilities:
	Derivative instruments, foreign exchange contracts		$	8		$	—		$	8
	Derivative instruments, other		9			—			9
	Total		$	17		$	—		$	17
	(1) Information with respect to these model-priced financial assets and liabilities is provided above in a separate table.
	(2) Fair value for these financial assets is measured using non-binding broker or dealer quotes.
	31-Dec-13		Significant Unobservable Inputs Readily Available to State Street(1)			Significant Unobservable Inputs Not Developed by State Street and Not Readily Available(2)			Total Assets and Liabilities with Significant Unobservable Inputs
	(In millions)
	Assets:
	U.S. Treasury and federal agencies, mortgage-backed securities		$	—		$	716		$	716
	Asset-backed securities, student loans		13			410			423
	Asset-backed securities, credit cards		24			—			24
	Asset-backed securities, other		92			4,440			4,532
	Non-U.S. debt securities, mortgage-backed securities		—			375			375
	Non-U.S. debt securities, asset-backed securities		—			798			798
	Non-U.S. debt securities, other		—			464			464
	State and political subdivisions		43			—			43
	Collateralized mortgage obligations		—			162			162
	Other U.S.debt securities		—			8			8
	Derivative instruments, foreign exchange contracts		19			—			19
	Total		$	191		$	7,373		$	7,564
	Liabilities:
	Derivative instruments, foreign exchange contracts		$	17		$	—		$	17
	Derivative instruments, other		9			—			9
	Total		$	26		$	—		$	26
	(1) Information with respect to these model-priced financial assets and liabilities is provided above in a separate table.
	(2) Fair value for these financial assets is measured using non-binding broker or dealer quotes.
Carrying Value and Estimated Fair Value of Financial Instruments by Fair Value Hierarchy	'
	The following tables present the reported amounts and estimated fair values of the financial instruments defined by GAAP, excluding financial assets and liabilities carried at fair value on a recurring basis, as they would be categorized within the fair-value hierarchy, as of the dates indicated.
									Fair-Value Hierarchy
	31-Mar-14		Reported Amount			Estimated Fair Value			Quoted Market Prices in Active Markets (Level 1)				Pricing Methods with Significant Observable Market Inputs (Level 2)			Pricing Methods with Significant Unobservable Market Inputs (Level 3)
	(In millions)
	Financial Assets:
	Cash and due from banks		$	3,877		$	3,877		$	3,877			$	—		$	—
	Interest-bearing deposits with banks		75,796			75,796			—				75,796			—
	Securities purchased under resale agreements		6,087			6,087			—				6,087			—
	Investment securities held to maturity		18,342			18,326			—				18,326			—
	Net loans (excluding leases)		14,994			15,002			—				14,530			472
	Financial Liabilities:
	Deposits:
	Noninterest-bearing		$	72,800		$	72,800		$	—			$	72,800		$	—
	Interest-bearing - U.S.		15,327			15,327			—				15,327			—
	Interest-bearing - non-U.S.		106,521			106,521			—				106,521			—
	Securities sold under repurchase agreements		8,953			8,953			—				8,953			—
	Federal funds purchased		18			18			—				18			—
	Other short-term borrowings		3,811			3,811			—				3,811			—
	Long-term debt		9,503			9,809			—				8,927			882
									Fair-Value Hierarchy
	31-Dec-13		Reported Amount			Estimated Fair Value			Quoted Market Prices in Active Markets (Level 1)				Pricing Methods with Significant Observable Market Inputs (Level 2)			Pricing Methods with Significant Unobservable Market Inputs (Level 3)
	(In millions)
	Financial Assets:
	Cash and due from banks		$	3,220		$	3,220		$	3,220			$	—		$	—
	Interest-bearing deposits with banks		64,257			64,257			—				64,257			—
	Securities purchased under resale agreements		6,230			6,230			—				6,230			—
	Investment securities held to maturity		17,740			17,560			—				17,560			—
	Net loans (excluding leases)		12,363			12,355			—				11,908			447
	Financial Liabilities:
	Deposits:
	Noninterest-bearing		$	65,614		$	65,614		$	—			$	65,614		$	—
	Interest-bearing - U.S.		13,392			13,392			—				13,392			—
	Interest-bearing - non-U.S.		103,262			103,262			—				103,262			—
	Securities sold under repurchase agreements		7,953			7,953			—				7,953			—
	Federal funds purchased		19			19			—				19			—
	Other short-term borrowings		3,780			3,780			—				3,780			—
	Long-term debt		9,699			9,909			—				9,056			853

Investment_Securities_Tables

Investment Securities (Tables)	3 Months Ended
	Mar. 31, 2014
Investments, Debt and Equity Securities [Abstract]	'
Schedule of Marketable Securities	'
	The following table presents the amortized cost and fair value, and associated unrealized gains and losses, of investment securities as of the dates indicated:
		March 31, 2014										December 31, 2013
		Amortized			Gross					Fair		Amortized		Gross				Fair
		Cost			Unrealized					Value		Cost		Unrealized				Value
	(In millions)				Gains			Losses						Gains		Losses
	Available for sale:
	U.S. Treasury and federal agencies:
	Direct obligations	$	1,959		$	10		$	6	$	1,963	$	702	$	9	$	2	$	709
	Mortgage-backed securities	23,176			206			290		23,092		23,744		211		392		23,563
	Asset-backed securities:
	Student loans(1)	14,355			128			203		14,280		14,718		92		268		14,542
	Credit cards	7,253			21			37		7,237		8,230		21		41		8,210
	Sub-prime	1,234			3			82		1,155		1,291		3		91		1,203
	Other	4,767			133			20		4,880		4,949		138		23		5,064
	Total asset-backed securities	27,609			285			342		27,552		29,188		254		423		29,019
	Non-U.S. debt securities:
	Mortgage-backed securities	10,978			225			7		11,196		10,808		230		9		11,029
	Asset-backed securities	4,973			23			2		4,994		5,369		23		2		5,390
	Government securities	3,689			3			—		3,692		3,759		2		—		3,761
	Other	4,931			62			9		4,984		4,679		59		11		4,727
	Total non-U.S. debt securities	24,571			313			18		24,866		24,615		314		22		24,907
	State and political subdivisions	10,345			216			117		10,444		10,301		160		198		10,263
	Collateralized mortgage obligations	5,253			67			58		5,262		5,275		70		76		5,269
	Other U.S. debt securities	4,827			139			20		4,946		4,876		138		34		4,980
	U.S. equity securities	29			7			—		36		28		6		—		34
	Non-U.S. equity securities	1			—			—		1		1		—		—		1
	U.S. money-market mutual funds	993			—			—		993		422		—		—		422
	Non-U.S. money-market mutual funds	7			—			—		7		7		—		—		7
	Total	$	98,770		$	1,243		$	851	$	99,162	$	99,159	$	1,162	$	1,147	$	99,174
	Held to maturity:
	U.S. Treasury and federal agencies:
	Direct obligations	$	5,096		$	—		$	328	$	4,768	$	5,041	$	—	$	448	$	4,593
	Mortgage-backed securities	81			6			—		87		91		6		—		97
	Asset-backed securities:
	Student loans(1)	1,889			5			2		1,892		1,627		—		10		1,617
	Credit cards	897			3			—		900		762		1		—		763
	Other	738			1			1		738		782		1		2		781
	Total asset-backed securities	3,524			9			3		3,530		3,171		2		12		3,161
	Non-U.S. debt securities:
	Mortgage-backed securities	4,323			172			29		4,466		4,211		150		48		4,313
	Asset-backed securities	2,399			19			—		2,418		2,202		19		—		2,221
	Government securities	2			—			—		2		2		—		—		2
	Other	192			—			—		192		192		—		—		192
	Total non-U.S. debt securities	6,916			191			29		7,078		6,607		169		48		6,728
	State and political subdivisions	16			—			—		16		24		1		—		25
	Collateralized mortgage obligations	2,709			163			25		2,847		2,806		176		26		2,956
	Total	$	18,342		$	369		$	385	$	18,326	$	17,740	$	354	$	534	$	17,560
	(1) Substantially composed of securities guaranteed by the federal government with respect to at least 97% of defaulted principal and
	accrued interest on the underlying loans.
Schedule of Gross Pre-tax Unrealized Losses on Investment Securities	'
	The following tables present the aggregate fair values of investment securities that have been in a continuous unrealized loss position for less than 12 months, and those that have been in a continuous unrealized loss position for 12 months or longer, as of the dates indicated:
		Less than 12 months						12 months or longer				Total
	March 31, 2014	Fair			Gross			Fair		Gross		Fair		Gross
		Value			Unrealized			Value		Unrealized		Value		Unrealized
	(In millions)				Losses					Losses				Losses
	Available for sale:
	U.S. Treasury and federal agencies:
	Direct obligations	$	1,433		$	5		$	130	$	1	$	1,563	$	6
	Mortgage-backed securities	9,475			197			3,161		93		12,636		290
	Asset-backed securities:
	Student loans	606			5			7,271		198		7,877		203
	Credit cards	3,311			26			214		11		3,525		37
	Sub-prime	—			—			1,106		82		1,106		82
	Other	1,997			10			418		10		2,415		20
	Total asset-backed securities	5,914			41			9,009		301		14,923		342
	Non-U.S. debt securities:
	Mortgage-backed securities	819			2			326		5		1,145		7
	Asset-backed securities	280			1			71		1		351		2
	Other	1,652			6			149		3		1,801		9
	Total non-U.S. debt securities	2,751			9			546		9		3,297		18
	State and political subdivisions	1,850			49			1,311		68		3,161		117
	Collateralized mortgage obligations	1,444			34			551		24		1,995		58
	Other U.S. debt securities	783			13			60		7		843		20
	Total	$	23,650		$	348		$	14,768	$	503	$	38,418	$	851
	Held to maturity:
	U.S. Treasury and federal agencies:
	Direct obligations	$	4,751		$	328		$	—	$	—	$	4,751	$	328
	Asset-backed securities:
	Student loans	297			1			176		1		473		2
	Other	129			1			—		—		129		1
	Total asset-backed securities	426			2			176		1		602		3
	Non-U.S. mortgage-backed securities	906			2			825		27		1,731		29
	Collateralized mortgage obligations	595			11			407		14		1,002		25
	Total	$	6,678		$	343		$	1,408	$	42	$	8,086	$	385
		Less than 12 months						12 months or longer				Total
	December 31, 2013	Fair			Gross			Fair		Gross		Fair		Gross
		Value			Unrealized			Value		Unrealized		Value		Unrealized
	(In millions)				Losses					Losses				Losses
	Available for sale:
	U.S. Treasury and federal agencies:
	Direct obligations	$	182		$	1		$	113	$	1	$	295	$	2
	Mortgage-backed securities	10,562			316			2,389		76		12,951		392
	Asset-backed securities:
	Student loans	1,930			16			7,252		252		9,182		268
	Credit cards	3,714			30			161		11		3,875		41
	Sub-prime	—			—			1,150		91		1,150		91
	Other	1,896			12			439		11		2,335		23
	Total asset-backed securities	7,540			58			9,002		365		16,542		423
	Non-U.S. debt securities:
	Mortgage-backed securities	868			2			258		7		1,126		9
	Asset-backed securities	551			1			16		1		567		2
	Other	1,655			9			150		2		1,805		11
	Total non-U.S. debt securities	3,074			12			424		10		3,498		22
	State and political subdivisions	3,242			113			1,268		85		4,510		198
	Collateralized mortgage obligations	1,581			55			510		21		2,091		76
	Other U.S. debt securities	1,039			25			58		9		1,097		34
	Total	$	27,220		$	580		$	13,764	$	567	$	40,984	$	1,147
	Held to maturity:
	U.S. Treasury and federal agencies:
	Direct obligations	$	4,571		$	448		$	—	$	—	$	4,571	$	448
	Asset-backed securities:
	Student Loans	1,352			10			—		—		1,352		10
	Other	297			1			29		1		326		2
Total asset-backed securities	1,649			11			29		1		1,678		12
Non-U.S. mortgage-backed securities	834			3			878		45		1,712		48
Collateralized mortgage obligations	759			18			161		8		920		26
Total	$	7,813		$	480		$	1,068	$	54	$	8,881	$	534
Investments Classified by Contractual Maturity Date	'
	The following table presents contractual maturities of debt investment securities as of March 31, 2014:
	(In millions)	Under 1			1 to 5			6 to 10		Over 10
		Year			Years			Years		Years
	Available for sale:
	U.S. Treasury and federal agencies:
	Direct obligations	$	2		$	526		$	835	$	600
	Mortgage-backed securities	183			2,387			5,276		15,246
	Asset-backed securities:
	Student loans	647			6,608			4,216		2,809
	Credit cards	2,187			3,057			1,993		—
	Sub-prime	7			20			1		1,127
	Other	469			1,314			1,381		1,716
	Total asset-backed securities	3,310			10,999			7,591		5,652
	Non-U.S. debt securities:
	Mortgage-backed securities	1,698			5,562			247		3,689
	Asset-backed securities	355			3,906			599		134
	Government securities	2,537			1,155			—		—
	Other	1,658			2,625			701		—
	Total non-U.S. debt securities	6,248			13,248			1,547		3,823
	State and political subdivisions	672			3,122			4,049		2,601
	Collateralized mortgage obligations	453			1,458			1,059		2,292
	Other U.S. debt securities	437			3,761			715		33
	Total	$	11,305		$	35,501		$	21,072	$	30,247
	Held to maturity:
	U.S. Treasury and federal agencies:
	Direct obligations	$	—		$	—		$	5,000	$	96
	Mortgage-backed securities	—			19			16		46
	Asset-backed securities
	Student loans	19			192			383		1,295
	Credit cards	—			335			562		—
	Other	23			447			263		5
	Total asset-backed securities	42			974			1,208		1,300
	Non-U.S. debt securities:
	Mortgage-backed securities	23			1,191			194		2,915
	Asset-backed securities	70			2,085			244		—
	Government securities	2			—			—		—
	Other	166			25			—		1
	Total non-U.S. debt securities	261			3,301			438		2,916
	State and political subdivisions	13			3			—		—
	Collateralized mortgage obligations	238			960			496		1,015
	Total	$	554		$	5,257		$	7,158	$	5,373
Gains and Losses Related to Investment Securities	'
	The following table presents gross realized gains and gross realized losses from sales of available-for-sale securities and the components of net impairment losses, included in net gains and losses related to investment securities, for the periods indicated:
		Three Months Ended March 31,
	(In millions)	2014			2013
	Gross realized gains from sales of available-for-sale securities	$	15		$	57
	Gross realized losses from sales of available-for-sale securities	—			(52		)
	Net impairment losses:
	Gross losses from other-than-temporary impairment	(1		)	—
	Losses reclassified (from) to other comprehensive income	(8		)	(3		)
	Net impairment losses(1)	(9		)	(3		)
	Gains related to investment securities, net	$	6		$	2
	(1) Net impairment losses, recognized in our consolidated statement of income, were composed of the following:
	Impairment associated with expected credit losses	$	(9	)	$	—
	Impairment associated with adverse changes in timing of expected future cash flows	—			(3		)
	Net impairment losses	$	(9	)	$	(3	)
Schedule of Credit-Related Loss Activity Recognized in Earnings	'
	The following table presents activity with respect to net impairment losses for the periods indicated:
		Three Months Ended March 31,
	(In millions)	2014			2013
	Beginning balance	$	122		$	124
	Plus losses for which other-than-temporary impairment was previously recognized	9			3
	Less previously recognized losses related to securities sold or matured	(1		)	—
	Less losses related to securities intended or required to be sold	(6		)	—
	Ending balance	$	124		$	127

Loans_and_Leases_Tables

Loans and Leases (Tables)	3 Months Ended
	Mar. 31, 2014
Loans and Leases Receivable Disclosure [Abstract]	'
Net Loans	'
	The following table presents our recorded investment in loans and leases, by segment and class, as of the dates indicated:
	(In millions)	March 31, 2014			December 31, 2013
	Institutional:
	Investment funds:
	U.S.	$	10,000		$	8,695
	Non-U.S.	2,310			1,718
	Commercial and financial:
	U.S.	1,895			1,372
	Non-U.S.	363			154
	Purchased receivables:
	U.S.	202			217
	Non-U.S.	20			26
	Lease financing:
	U.S.	337			339
	Non-U.S.	753			756
	Total institutional	15,880			13,277
	Commercial real estate:
	U.S.	234			209
	Total loans and leases	16,114			13,486
	Allowance for loan losses	(30		)	(28		)
	Loans and leases, net of allowance for loan losses	$	16,084		$	13,458
Schedule of Components of Leveraged Lease Investments	'
Recorded Investment in Each Class of Total Loans and Leases by Credit Quality Indicator	'
	The following tables present our recorded investment in each class of loans and leases by credit quality indicator as of the dates indicated:
		Institutional										Commercial Real Estate
	March 31, 2014	Investment			Commercial and Financial			Purchased		Lease		Property Development		Other		Total
		Funds						Receivables		Financing						Loans and
	(In millions)															Leases
	Investment grade(1)	$	12,073		$	961		$	222	$	1,037	$	—	$	29	$	14,322
	Speculative(2)	237			1,281			—		53		205		—		1,776
	Special mention(3)	—			16			—		—		—		—		16
	Total	$	12,310		$	2,258		$	222	$	1,090	$	205	$	29	$	16,114
		Institutional										Commercial Real Estate
	December 31, 2013	Investment			Commercial and Financial			Purchased		Lease		Property Development		Other		Total
		Funds						Receivables		Financing						Loans and
	(In millions)															Leases
	Investment grade(1)	$	10,282		$	740		$	243	$	1,068	$	—	$	29	$	12,362
	Speculative(2)	131			770			—		27		180		—		1,108
	Special mention(3)	—			16			—		—		—		—		16
	Total	$	10,413		$	1,526		$	243	$	1,095	$	180	$	29	$	13,486
	(1) Investment-grade loans and leases consist of counterparties with strong credit quality and low expected credit risk and probability of default. Ratings apply to counterparties with a strong capacity to support the timely repayment of any financial commitment.
	(2) Speculative loans and leases consist of counterparties that face ongoing uncertainties or exposure to business, financial, or economic downturns. However, these counterparties may have financial flexibility or access to financial alternatives, which allow for financial commitments to be met.
	(3) Special mention loans and leases consist of counterparties with potential weaknesses that, if uncorrected, may result in deterioration of repayment prospects.
Schedule of Loans and Leases Receivable by Impairment Methodology	'
	The following table presents our recorded investment in loans and leases, disaggregated based on our impairment methodology, as of the dates indicated:
		March 31, 2014								December 31, 2013
	(In millions)	Institutional			Commercial Real Estate			Total Loans and Leases		Institutional		Commercial Real Estate		Total Loans and Leases
	Loans and leases:
	Individually evaluated for impairment	$	—		$	130		$	130	$	26	$	180	$	206
	Collectively evaluated for impairment(1)	15,880			104			15,984		13,251		29		13,280
	Total	$	15,880		$	234		$	16,114	$	13,277	$	209	$	13,486
	(1) As of March 31, 2014 and December 31, 2013, all of the allowance for loan losses of $30 million and $28 million, respectively, related to institutional loans collectively evaluated for impairment.
Impaired Loans	'
	The following tables present information related to our recorded investment in impaired loans and leases as of the dates, or for the periods, indicated:
		March 31, 2014								December 31, 2013
	(In millions)	Recorded Investment			Unpaid			Related Allowance(1)		Recorded Investment		Unpaid		Related Allowance(1)
					Principal							Principal
					Balance							Balance
	With no related allowance recorded:
	CRE—property development	$	130		$	143		$	—	$	130	$	143	$	—
	CRE—property development—acquired credit-impaired	—			34			—		—		34		—
	CRE—other—acquired credit-impaired	—			21			—		—		21		—
	Total CRE	$	130		$	198		$	—	$	130	$	198	$	—
	(1) As of March 31, 2014 and December 31, 2013, all of the allowance for loan losses of $30 million and $28 million, respectively, related to loans that were not impaired.
		Three Months Ended March 31,
		Average Recorded Investment						Interest Revenue Recognized
		2014			2013			2014		2013
	(In millions)
	With no related allowance recorded:
	CRE—property development	$	130		$	195		$	2	$	4
	Total CRE	$	130		$	195		$	2	$	4
Schedule of Activity in the Allowance for Loan Losses	'
	The following table presents activity in the allowance for loan losses for the periods indicated:
		Three Months Ended March 31,
		2014								2013
	(In millions)	Institutional			Commercial			Total Loans and Leases		Institutional		Commercial		Total Loans and Leases
					Real Estate							Real Estate
	Allowance for loan losses:
	Beginning balance	$	28		$	—		$	28	$	22	$	—	$	22
	Provisions	2			—			2		—		—		—
	Ending balance	$	30		$	—		$	30	$	22	$	—	$	22

Goodwill_and_Other_Intangible_1

Goodwill and Other Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Changes In The Carrying Amount Of Goodwill	'
		Three Months Ended March 31,
		2014									2013
	(In millions)	Investment			Investment			Total			Investment			Investment			Total
		Servicing			Management						Servicing			Management
	Goodwill:
	Beginning balance	$	5,999		$	37		$	6,036		$	5,941		$	36		$	5,977
	Foreign currency translation, net	2			—			2			(64		)	(1		)	(65		)
	Ending balance	$	6,001		$	37		$	6,038		$	5,877		$	35		$	5,912
Changes In The Carrying Amount Of Other Intangible Assets	'
	The following table presents changes in the net carrying amount of other intangible assets during the periods indicated:
		Three Months Ended March 31,
		2014									2013
	(In millions)	Investment			Investment			Total			Investment			Investment			Total
		Servicing			Management						Servicing			Management
	Other intangible assets:
	Beginning balance	$	2,321		$	39		$	2,360		$	2,492		$	47		$	2,539
	Amortization	(52		)	(2		)	(54		)	(51		)	(2		)	(53		)
	Foreign currency translation, net	—			—			—			(32		)	(2		)	(34		)
	Ending balance	$	2,269		$	37		$	2,306		$	2,409		$	43		$	2,452
Schedule of Finite-Lived Intangible Assets	'
		March 31, 2014									December 31, 2013
	(In millions)	Gross			Accumulated			Net			Gross			Accumulated			Net
		Carrying			Amortization			Carrying			Carrying			Amortization			Carrying
		Amount						Amount			Amount						Amount
	Client relationships	$	2,702		$	(1,011	)	$	1,691		$	2,706		$	(975	)	$	1,731
	Core deposits	717			(200		)	517			717			(191		)	526
	Other	230			(132		)	98			234			(131		)	103
	Total	$	3,649		$	(1,343	)	$	2,306		$	3,657		$	(1,297	)	$	2,360

Other_Assets_Tables

Other Assets (Tables)	3 Months Ended
	Mar. 31, 2014
Other Assets [Abstract]	'
Components of Other Assets	'
	The following table presents the components of other assets as of the dates indicated:
	(In millions)	March 31, 2014		December 31, 2013
	Collateral deposits, net	$	13,518	$	13,706
	Unrealized gains on derivative financial instruments, net	3,469		5,476
	Bank-owned life insurance	2,359		2,343
	Investments in joint ventures and other unconsolidated entities	1,712		1,644
	Accounts receivable	687		950
	Prepaid expenses	359		286
	Income taxes receivable	339		337
	Receivable for securities settlement	334		195
	Deferred tax assets, net of valuation allowance	249		263
	Receivable for securities sold	191		—
	Deposits with clearing organizations	183		177
	Other(1)	589		613
	Total	$	23,989	$	25,990
	(1)	Included other real estate owned of approximately $60 million and $59 million as of March 31, 2014 and December 31, 2013, respectively.

Contingencies_Tables

Contingencies (Tables)	3 Months Ended
	Mar. 31, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Schedule of Total Worldwide Revenue from Foreign Exchanges	'
	The following table summarizes our estimated total revenue worldwide from indirect foreign exchange trading services for the periods indicated:
	(In millions)	Revenue from indirect foreign exchange trading
	2008	$	462
	2009	369
	2010	336
	2011	331
	2012	248
	2013	285
	Three Months Ended March 31, 2014	63

Commitments_and_Guarantees_Tab

Commitments and Guarantees (Tables)	3 Months Ended
	Mar. 31, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Schedule of Guarantor Obligations	'
	The following table presents the aggregate gross contractual amounts of our off-balance sheet guarantees as of the dates indicated. Amounts presented do not reflect participations to independent third parties.
	(In millions)	March 31, 2014		December 31, 2013
	Indemnified securities financing	$	346,789	$	320,078
	Stable value protection	24,484		24,906
	Asset purchase agreements	4,304		4,685
	Standby letters of credit	4,870		4,612
Schedule of Repurchase Agreements	'
	The following table summarizes the fair values of indemnified securities financing and related collateral, as well as collateral invested in indemnified repurchase agreements, as of the dates indicated:
	(In millions)	March 31, 2014		December 31, 2013
	Aggregate fair value of indemnified securities financing	$	346,789	$	320,078
	Aggregate fair value of cash and securities held by us, as agent, as collateral for indemnified securities financing	358,240		331,732
	Aggregate fair value of collateral for indemnified securities financing invested in indemnified repurchase agreements	94,423		85,374
	Aggregate fair value of cash and securities held by us or our agents as collateral for investments in indemnified repurchase agreements	99,935		91,097

Shareholders_Equity_Tables

Shareholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2014
Stockholders' Equity Note [Abstract]	'
Schedule of Accumulated Other Comprehensive Income (Loss)	'
	The following tables presents changes in AOCI by component, net of related taxes, for the periods indicated:
		Three Months Ended March 31, 2014
	(In millions)	Net Unrealized Gains (Losses) on Cash Flow Hedges			Net Unrealized Gains (Losses) on Available-for-Sale Securities			Net Unrealized Losses on Hedges of Net Investments in Non-U.S. Subsidiaries			Other-Than-Temporary Impairment on Held-to-Maturity Securities			Net Unrealized Losses on Retirement Plans			Foreign Currency Translation			Total
	Beginning balance	$	161		$	(221	)	$	(14	)	$	(47	)	$	(203	)	$	229		$	(95	)
	Other comprehensive income (loss) before reclassifications	(8		)	258			—			8			1			27			286
	Amounts reclassified out of AOCI	1			(9		)	—			—			5			—			(3		)
	Other comprehensive income (loss)	(7		)	249			—			8			6			27			283
	Ending balance	$	154		$	28		$	(14	)	$	(39	)	$	(197	)	$	256		$	188
		Three Months Ended March 31, 2013
	(In millions)	Net Unrealized Gains (Losses) on Cash Flow Hedges			Net Unrealized Gains (Losses) on Available-for-Sale Securities			Net Unrealized Losses on Hedges of Net Investments in Non-U.S. Subsidiaries			Other-Than-Temporary Impairment on Held-to-Maturity Securities			Net Unrealized Losses on Retirement Plans			Foreign Currency Translation			Total
	Beginning balance	$	69		$	519		$	(14	)	$	(65	)	$	(283	)	$	134		$	360
	Other comprehensive income (loss) before reclassifications	63			69			—			4			(2		)	(248		)	(114		)
	Amounts reclassified out of AOCI	1			(3		)	—			2			5			—			5
	Other comprehensive income (loss)	64			66			—			6			3			(248		)	(109		)
	Ending balance	$	133		$	585		$	(14	)	$	(59	)	$	(280	)	$	(114	)	$	251
	The following table presents the after-tax components of AOCI as of the dates indicated:
	(In millions)	March 31, 2014			December 31, 2013
	Net unrealized gains on cash flow hedges	$	154		$	161
	Net unrealized gains (losses) on available-for-sale securities portfolio	194			(56		)
	Net unrealized losses related to reclassified available-for-sale securities	(61		)	(72		)
	Net unrealized gains (losses) on available-for-sale securities	133			(128		)
	Net unrealized losses on available-for-sale securities designated in fair value hedges	(107		)	(97		)
	Other-than-temporary impairment on available-for-sale securities related to factors other than credit	2			4
	Net unrealized losses on hedges of net investments in non-U.S. subsidiaries	(14		)	(14		)
	Other-than-temporary impairment on held-to-maturity securities related to factors other than credit	(39		)	(47		)
	Net unrealized losses on retirement plans	(197		)	(203		)
	Foreign currency translation	256			229
	Total	$	188		$	(95	)
Schedule of Reclassifications Out of AOCI	'
	The following table presents after-tax reclassifications out of AOCI for the periods indicated:
		Three Months Ended March 31,
		2014			2013
	(In millions)	Amounts Reclassified out of AOCI						Affected Line Item in Consolidated Statement of Income
	Cash flow hedges:
	Interest-rate contracts	$	1		$	1		Net interest revenue
	Available-for-sale securities:
	Net realized gains from sales of available-for-sale securities, net of related taxes of ($6) and ($2), respectively	(9		)	(3		)	Net gains (losses) from sales of available-for-sale securities
	Held-to-maturity securities:
	Other-than-temporary impairment on held-to-maturity securities related to factors other than credit, net of related tax benefit of $1	—			2			Losses reclassified (from) to other comprehensive income
	Retirement plans:
	Amortization of actuarial losses, net of related tax benefits of $3 and $3, respectively	5			5			Compensation and employee benefits expenses
	Total reclassifications out of AOCI	$	(3	)	$	5

Derivative_Financial_Instrumen1

Derivative Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Schedule of Outstanding Hedges: (Notional Amount)	'
	For cash flow hedges, any changes in the fair value of the derivative financial instruments remain in AOCI, and are generally recorded in our consolidated statement of income in future periods when earnings are affected by the var
Notional Amount of Interest Rate Swap Agreements Designated as Fair Value and Cash Flow Hedges	'
	The following table presents the aggregate notional amounts of these interest-rate contracts and the related assets or liabilities being hedged as of the dates indicated:
		March 31, 2014												December 31, 2013
	(In millions)	Fair				Cash				Total				Fair				Cash				Total
		Value				Flow								Value				Flow
		Hedges				Hedges								Hedges				Hedges
	Investment securities available for sale	$	2,589			$	133			$	2,722			$	2,589			$	132			$	2,721
	Long-term debt(1)	2,500				—				2,500				2,500				—				2,500
	Total	$	5,089			$	133			$	5,222			$	5,089			$	132			$	5,221
	(1) As of March 31, 2014, these fair value hedges increased the carrying value of long-term debt presented in our consolidated statement of condition by $3 million. As of December 31, 2013, these fair value hedges decreased the carrying value of long-term debt presented in our consolidated statement of condition by $35 million.
Contractual and Weighted-Average Interest Rates, Which Include the Effects of Hedges Related to Financial Instruments	'
	The following table presents the contractual and weighted-average interest rates for long-term debt, which include the effects of the fair value hedges presented in the table above, for the periods indicated:
		Three Months Ended March 31,
		2014						2013
		Contractual			Rate Including			Contractual			Rate Including
		Rates			Impact of Hedges			Rates			Impact of Hedges
	Long-term debt	3.39	%		2.6	%		3.77	%		3.03	%
Schedule of the Fair Values of Derivative Financial Instruments	'
	The following tables present the fair value of derivative financial instruments, excluding the impact of master netting agreements, recorded in our
	consolidated statement of condition as of the dates indicated. The impact of master netting agreements is disclosed in note 2.
		Asset Derivatives
		Balance Sheet		Fair Value
		Location
	(In millions)			March 31, 2014				December 31, 2013
	Derivatives not designated as hedging instruments:
	Foreign exchange contracts	Other assets		$	8,012			$	11,552
	Interest-rate contracts	Other assets		21				29
	Other derivative contracts	Other assets		2				1
	Total			$	8,035			$	11,582
	Derivatives designated as hedging instruments:
	Foreign exchange contracts	Other assets		$	306			$	359
	Interest-rate contracts	Other assets		35				36
	Total			$	341			$	395
		Liability Derivatives
		Balance Sheet		Fair Value
		Location
	(In millions)			March 31, 2014				December 31, 2013
	Derivatives not designated as hedging instruments:
	Foreign exchange contracts	Other liabilities		$	7,771			$	11,428
	Interest-rate contracts	Other liabilities		21				29
	Other derivative contracts	Other liabilities		10				9
	Total			$	7,802			$	11,466
	Derivatives designated as hedging instruments:
	Interest-rate contracts	Other liabilities		$	248			$	302
	Foreign exchange contracts	Other liabilities		71				43
	Total			$	319			$	345
Impact of Derivatives on Consolidated Statement of Income	'
	The following tables present the impact of our use of derivative financial instruments on our consolidated statement of income for the periods indicated:
		Location of Gain (Loss) on		Amount of Gain (Loss) on Derivative Recognized in
		Derivative in Consolidated		Consolidated Statement
		Statement of Income		of Income
				Three Months Ended March 31,
	(In millions)			2014				2013
	Derivatives not designated as hedging instruments:
	Foreign exchange contracts	Trading services revenue		$	134			$	145
	Interest-rate contracts	Trading services revenue		—				1
	Other derivative contracts	Processing fees and other revenue		(1		)		—
	Total			$	133			$	146
Schedule of Differences Between the Gains (Losses) on the Derivative and the Gains (Losses) on the Hedged Item	'
		Location of Gain (Loss) on Derivative in Consolidated Statement of Income		Amount of Gain								Hedged Item in Fair Value Hedging Relationship		Location of Gain (Loss) on Hedged Item in Consolidated Statement of Income		Amount of Gain
				(Loss) on Derivative												(Loss) on Hedged
				Recognized in												Item Recognized in
				Consolidated												Consolidated
				Statement of Income												Statement of Income
	(In millions)			Three Months Ended March 31,												Three Months Ended March 31,
	Derivatives designated as fair value hedges:			2014				2013								2014				2013
	Foreign exchange contracts	Processing fees and		$	42			$	4			Investment securities		Processing fees and		$	(42	)		$	(4	)
		other revenue												other revenue
	Interest-rate contracts	Processing fees and		(12		)		1				Available-for-sale securities		Processing fees and		12				(2		)
		other revenue												other revenue
	Interest-rate contracts	Processing fees and		49				(15		)		Long-term debt		Processing fees and		(45		)		16
		other revenue												other revenue
	Total			$	79			$	(10	)						$	(75	)		$	10
	Differences between the gains (losses) on the derivative and the gains (losses) on the hedged item,
	excluding any amounts recorded in net interest revenue, represent hedge ineffectiveness.
		Amount of Gain								Location of Gain (Loss) Reclassified from OCI to Consolidated Statement of Income		Amount of Gain								Location of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income		Amount of Gain
		(Loss) on Derivative										(Loss) Reclassified										(Loss) on Derivative
		Recognized in Other										from OCI to										Recognized in
		Comprehensive										Consolidated										Consolidated
		Income										Statement of Income										Statement of Income
		Three Months Ended March 31,										Three Months Ended March 31,										Three Months Ended March 31,
	(In millions)	2014				2013						2014				2013						2014		2013
	Derivatives designated as cash flow hedges:
	Interest-rate contracts	$	(1	)		$	12			Net interest revenue		$	(1	)		$	(1	)		Net interest revenue		$	1	$	1
	Foreign exchange contracts	(12		)		105				Net interest revenue		—				—				Net interest revenue		1		3
	Total	$	(13	)		$	117					$	(1	)		$	(1	)				$	2	$	4

Offsetting_Arrangements_Tables

Offsetting Arrangements (Tables)	3 Months Ended
	Mar. 31, 2014
Offsetting [Abstract]	'
Offsetting Assets	'
	The following tables present information about the offsetting of assets related to derivative contracts and secured financing transactions, as of the dates indicated:
	Assets:	31-Mar-14								31-Dec-13
	(In millions)	Gross Amounts of Recognized Assets(1)		Gross Amounts Offset in Statement of Condition(2)			Net Amounts of Assets Presented in Statement of Condition			Gross Amounts of Recognized Assets(1)		Gross Amounts Offset in Statement of Condition(2)			Net Amounts of Assets Presented in Statement of Condition
	Derivatives:
	Interest-rate contracts	$	56	$	(45	)	$	11		$	65	$	(59	)	$	6
	Foreign exchange contracts	8,318		(3,489		)	4,829			11,911		(4,514		)	7,397
	Other derivative contracts	2		(1		)	1			1		—			1
	Cash collateral netting	—		(1,372		)	(1,372		)	—		(1,928		)	(1,928		)
	Total derivatives	$	8,376	$	(4,907	)	$	3,469		$	11,977	$	(6,501	)	$	5,476
	Other financial instruments:
	Resale agreements and securities borrowing(3)	$	47,715	$	(30,307	)	$	17,408		$	48,221	$	(30,700	)	$	17,521
	Total derivatives and other financial instruments	$	56,091	$	(35,214	)	$	20,877		$	60,198	$	(37,201	)	$	22,997
	(1) Amounts include all transactions regardless of whether or not they are subject to an enforceable netting arrangement.
	(2) Amounts subject to netting arrangements which have been determined to be legally enforceable.
	(3) Included in the $17,408 million as of March 31, 2014 was $6,087 million of resale agreements and $11,321 million of collateral provided related to securities borrowing. Included in the $17,521 million as of December 31, 2013 was $6,230 million of resale agreements and $11,291 million of collateral provided related to securities borrowing. Resale agreements and collateral provided related to securities borrowing were recorded in securities purchased under resale agreements and other assets, respectively, in our consolidated statement of condition. Refer to note 7 for additional information with respect to principal securities finance transactions.
		31-Mar-14										31-Dec-13
				Gross Amounts Not Offset in Statement of Condition(1)											Gross Amounts Not Offset in Statement of Condition(1)
	(In millions)	Net Amount of Assets Presented in Statement of Condition		Counterparty Netting			Collateral Received			Net Amount(2)		Net Amount of Assets Presented in Statement of Condition			Counterparty Netting			Collateral Received			Net Amount(2)
	Derivatives	$	3,469	$	—		$	(187	)	$	3,282	$	5,476		$	—		$	(181	)	$	5,295
	Resale agreements and securities borrowing	17,408		(113		)	(15,099		)	2,196		17,521			(131		)	(14,983		)	2,407
	Total	$	20,877	$	(113	)	$	(15,286	)	$	5,478	$	22,997		$	(131	)	$	(15,164	)	$	7,702
	(1) Amounts subject to netting arrangements which have been determined to be legally enforceable.
	(2) Includes amounts secured by collateral not determined to be subject to enforceable netting arrangements.
Offsetting Liabilities	'
	The following tables present information about the offsetting of liabilities related to derivative contracts and secured financing transactions, as of the dates indicated:
	Liabilities:	31-Mar-14								31-Dec-13
	(In millions)	Gross Amounts of Recognized Liabilities(1)		Gross Amounts Offset in Statement of Condition(2)			Net Amounts of Liabilities Presented in Statement of Condition			Gross Amounts of Recognized Liabilities(1)		Gross Amounts Offset in Statement of Condition(2)			Net Amounts of Liabilities Presented in Statement of Condition
	Derivatives:
	Interest-rate contracts	$	269	$	(45	)	$	224		$	331	$	(59	)	$	272
	Foreign exchange contracts	7,842		(3,489		)	4,353			11,471		(4,514		)	6,957
	Other derivative contracts	10		(1		)	9			9		—			9
	Cash collateral netting	—		(274		)	(274		)	—		(979		)	(979		)
	Total derivatives	$	8,121	$	(3,809	)	$	4,312		$	11,811	$	(5,552	)	$	6,259
	Other financial instruments:
	Repurchase agreements and securities lending(3)	$	45,545	$	(30,307	)	$	15,238		$	45,273	$	(30,700	)	$	14,573
	Total derivatives and other financial instruments	$	53,666	$	(34,116	)	$	19,550		$	57,084	$	(36,252	)	$	20,832
	(1) Amounts include all transactions regardless of whether or not they are subject to an enforceable netting arrangement.
	(2) Amounts subject to netting arrangements which have been determined to be legally enforceable.
	(3) Included in the $15,238 million as of March 31, 2014 was $8,953 million of repurchase agreements and $6,285 million of collateral received related to securities lending. Included in the $14,573 million as of December 31, 2013 was $7,953 million of repurchase agreements and $6,620 million of collateral received related to securities lending. Repurchase agreements and collateral received related to securities lending were recorded in securities sold under repurchase agreements and accrued expenses and other liabilities, respectively, in our consolidated statement of condition. Refer to note 7 for additional information with respect to principal securities finance transactions.
		31-Mar-14										31-Dec-13
				Gross Amounts Not Offset in Statement of Condition(1)											Gross Amounts Not Offset in Statement of Condition(1)
	(In millions)	Net Amount of Liabilities Presented in Statement of Condition		Counterparty Netting			Collateral Provided			Net Amount(2)		Net Amount of Liabilities Presented in Statement of Condition			Counterparty Netting			Collateral Provided			Net Amount(2)
	Derivatives	$	4,312	$	—		$	—		$	4,312	$	6,259		$	—		$	(6	)	$	6,253
	Repurchase agreements and securities lending	15,238		(113		)	(13,015		)	2,110		14,573			(131		)	(13,036		)	1,406
	Total	$	19,550	$	(113	)	$	(13,015	)	$	6,422	$	20,832		$	(131	)	$	(13,042	)	$	7,659
	(1) Amounts subject to netting arrangements which have been determined to be legally enforceable.
	(2) Includes amounts secured by collateral not determined to be subject to enforceable netting arrangements.

Net_Interest_Revenue_Tables

Net Interest Revenue (Tables)	3 Months Ended
	Mar. 31, 2014
Net Interest Revenue [Abstract]	'
Components of Interest Revenue and Interest Expense	'
	The following table presents the components of interest revenue and interest expense, and related net interest revenue, for the periods indicated:
		Three Months Ended March 31,
	(In millions)	2014		2013
	Interest revenue:
	Deposits with banks	$	34	$	31
	Investment securities:
	U.S. Treasury and federal agencies	163		194
	State and political subdivisions	71		51
	Other investments	319		341
	Securities purchased under resale agreements	9		13
	Loans and leases	58		56
	Other interest-earning assets	1		1
	Total interest revenue	655		687
	Interest expense:
	Deposits	15		34
	Short-term borrowings	15		16
	Long-term debt	63		56
	Other interest-bearing liabilities	7		5
	Total interest expense	100		111
	Net interest revenue	$	555	$	576

Expenses_Tables

Expenses (Tables)	3 Months Ended
	Mar. 31, 2014
Other Expenses [Abstract]	'
Schedule of Acquisition and Restructuring Costs	'
	The following table presents net acquisition and restructuring costs recorded in the periods indicated:
		Three Months Ended March 31,
	(In millions)	2014			2013
	Acquisition costs	$	21		$	15
	Restructuring charges, net	12			(1		)
	Total acquisition and restructuring costs	$	33		$	14
Costs Related to Acquisition and Restructuring	'
	(In millions)	Employee-			Real Estate Consolidation			Asset and Other Write-Offs			Total
		Related
		Costs
	Balance as of December 31, 2013	$	50		$	49		$	7		$	106
	Additional accruals for Business Operations and Information Technology Transformation program	6			3			—			9
	Additional accruals for 2012 expense control measures	—			—			3			3
	Payments and adjustments	(17		)	(12		)	(2		)	(31		)
	Balance as of March 31, 2014	$	39		$	40		$	8		$	87

Earnings_Per_Common_Share_Tabl

Earnings Per Common Share (Tables)	3 Months Ended
	Mar. 31, 2014
Earnings Per Share [Abstract]	'
Computation of Basic and Diluted Earnings Per Share	'
	The following table presents the computation of basic and diluted earnings per common share for the periods indicated:
		Three Months Ended March 31,
	(Dollars in millions, except per share amounts)	2014			2013
	Net income	$	363		$	464
	Less:
	Preferred stock dividends	(6		)	(7		)
	Dividends and undistributed earnings allocated to participating securities(1)	(1		)	(2		)
	Net income available to common shareholders	$	356		$	455
	Average common shares outstanding (in thousands):
	Basic average common shares	430,621			454,315
	Effect of dilutive securities: common stock options and common stock awards	8,194			8,436
	Diluted average common shares	438,815			462,751
	Anti-dilutive securities(2)	1,504			2,488
	Earnings per Common Share:
	Basic	$	0.83		$	1
	Diluted(3)	0.81			0.98
	(1) Represented the portion of net income available to common equity allocated to participating securities, composed of fully vested deferred director stock and unvested restricted stock that contain non-forfeitable rights to dividends during the vesting period on a basis equivalent to dividends paid to common shareholders.
	(2) Represented common stock options and other equity-based awards outstanding but not included in the computation of diluted average shares, because their effect was anti-dilutive.
	(3) Calculations reflect allocation of earnings to participating securities using the two-class method, as this computation is more dilutive than the treasury stock method.

Line_of_Business_Information_T

Line of Business Information (Tables)	3 Months Ended
	Mar. 31, 2014
Segment Reporting [Abstract]	'
Summary of Line of Business Results	'
		Three Months Ended March 31,
		Investment						Investment						Other						Total
		Servicing						Management
		2014			2013			2014			2013			2014			2013			2014			2013
	(Dollars in millions,
	except where otherwise noted)
	Fee revenue:
	Servicing fees	$	1,238		$	1,175		$	—		$	—		$	—		$	—		$	1,238		$	1,175
	Management fees	—			—			292			263			—			—			292			263
	Trading services	227			257			12			24			—			—			239			281
	Securities finance	85			78			—			—			—			—			85			78
	Processing fees and other	69			55			1			5			—			—			70			60
	Total fee revenue	1,619			1,565			305			292			—			—			1,924			1,857
	Net interest revenue	538			557			17			19			—			—			555			576
	Gains (losses) related to investment securities, net	6			2			—			—			—			—			6			2
	Total revenue	2,163			2,124			322			311			—			—			2,485			2,435
	Provision for loan losses	2			—			—			—			—			—			2			—
	Total expenses	1,673			1,590			244			222			111			14			2,028			1,826
	Income before income tax expense	$	488		$	534		$	78		$	89		$	(111	)	$	(14	)	$	455		$	609
	Pre-tax margin	23		%	25		%	24		%	29		%							18		%	25		%
	Average assets (in billions)	$	212.2		$	204.4		$	3.4		$	3.9								$	215.6		$	208.3

NonUS_Activities_Tables

Non-U.S. Activities (Tables)	3 Months Ended
	Mar. 31, 2014
Segments, Geographical Areas [Abstract]	'
Schedule of Results from Non-U.S. Operations	'
	The following table presents our non-U.S. financial results for the periods indicated.
		Three Months Ended March 31,
	(In millions)	2014		2013
	Total fee revenue	$	788	$	765
	Net interest revenue	325		273
	Gains (losses) related to investment securities, net	6		(3		)
	Total revenue	1,119		1,035
	Expenses	839		753
	Income before income taxes	280		282
	Income tax expense	65		69
	Net income	$	215	$	213
Summary of Non-U.S. Assets	'
	The following table presents the significant components of our non-U.S. assets as of the dates indicated, based on the domicile of the underlying counterparties:
	(In millions)	March 31, 2014		December 31, 2013
	Interest-bearing deposits with banks	$	10,281	$	9,584
	Investment securities	31,790		31,522
	Other assets	17,552		16,778
	Total non-U.S. assets	$	59,623	$	57,884

Basis_of_Presentation_Details

Basis of Presentation (Details)	3 Months Ended
	Mar. 31, 2014
	line_of_business
Accounting Policies [Abstract]	'
Number of lines of business	2

Fair_Value_Narrative_Details

Fair Value (Narrative) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'	'
Fair value measurements with unobservable inputs, percent of total financial assets	6.00%	'
Percent of level 3 portfolio priced using non-binding broker quotes	98.00%	98.00%
Percent of level 3 portfolio priced using internal model pricing	2.00%	2.00%
Assets, level 1 to level 2 transfers	$0	$0
Assets, level 2 to level 1 transfers	0	0
Liabilities, level 1 to level 2 transfers	0	0
Liabilities, level 2 to level 1 transfers	$0	$0

Fair_Value_Schedule_of_Fair_Va

Fair Value (Schedule of Fair Value Measurements on a Recurring Basis) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	$889,000,000		'	$843,000,000
Investment securities available for sale	99,162,000,000		'	99,174,000,000
Reduction in assets from netting and the result of cash collateral deposited with derivative counterparties	1,370,000,000		1,930,000,000	'
Reduction in liabilities from netting and the result of cash collateral received from derivative counterparties	274,000,000		979,000,000	'
Pricing Methods with Significant Unobservable Market Inputs (Level 3)	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Assets, fair value disclosure	6,069,000,000		'	7,564,000,000
Liabilities, fair value disclosure	17,000,000		'	26,000,000
Recurring	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	889,000,000		'	843,000,000
Investment securities available for sale	99,162,000,000		'	99,174,000,000
Derivative assets	3,469,000,000		'	5,476,000,000
Other assets	100,000,000		'	97,000,000
Assets, fair value disclosure	103,620,000,000		'	105,590,000,000
Derivative instruments, liabilities	4,312,000,000		'	6,259,000,000
Other liabilities	100,000,000		'	97,000,000
Liabilities, fair value disclosure	4,412,000,000		'	6,356,000,000
Recurring | Foreign exchange contracts	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	3,468,000,000		'	5,469,000,000
Derivative instruments, liabilities	4,090,000,000		'	6,013,000,000
Recurring | Interest-rate contracts	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	0		'	6,000,000
Derivative instruments, liabilities	213,000,000		'	237,000,000
Recurring | Other	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	1,000,000		'	1,000,000
Derivative instruments, liabilities	9,000,000		'	9,000,000
Recurring | U.S. government securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	20,000,000		'	20,000,000
Recurring | Non-U.S. government securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	401,000,000		'	399,000,000
Recurring | US Treasury and federal agencies, direct obligations	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	1,963,000,000		'	709,000,000
Recurring | US Treasury and federal agencies, mortgage-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	23,092,000,000		'	23,563,000,000
Recurring | Total asset-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	27,552,000,000		'	29,019,000,000
Recurring | Asset-backed securities, student loans	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	14,280,000,000		'	14,542,000,000
Recurring | Asset-backed securities, credit cards	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	7,237,000,000		'	8,210,000,000
Recurring | Asset-backed securities, sub-prime	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	1,155,000,000		'	1,203,000,000
Recurring | Asset-backed securities, other	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	4,880,000,000		'	5,064,000,000
Recurring | Total non-U.S. debt securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	24,866,000,000		'	24,907,000,000
Recurring | Non-U.S. debt securities, mortgage-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	11,196,000,000		'	11,029,000,000
Recurring | Non-U.S. debt securities, asset-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	4,994,000,000		'	5,390,000,000
Recurring | Non-US debt securities, government securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	3,692,000,000		'	3,761,000,000
Recurring | Non-U.S. debt securities, other	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	4,984,000,000		'	4,727,000,000
Recurring | State and political subdivisions	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	10,444,000,000		'	10,263,000,000
Recurring | Collateralized mortgage obligations	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	5,262,000,000		'	5,269,000,000
Recurring | Other U.S.debt securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	468,000,000		'	424,000,000
Investment securities available for sale	4,946,000,000		'	4,980,000,000
Recurring | U.S. equity securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	36,000,000		'	34,000,000
Recurring | Non-U.S. equity securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	1,000,000		'	1,000,000
Recurring | U.S. money-market mutual funds	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	993,000,000		'	422,000,000
Recurring | Non-U.S. money-market mutual funds	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	7,000,000		'	7,000,000
Recurring | Quoted Market Prices in Active Markets (Level 1)	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	481,000,000		'	486,000,000
Investment securities available for sale	1,280,000,000		'	0
Derivative assets	0		'	0
Other assets	100,000,000		'	97,000,000
Assets, fair value disclosure	1,861,000,000		'	583,000,000
Derivative instruments, liabilities	0		'	0
Other liabilities	100,000,000		'	97,000,000
Liabilities, fair value disclosure	100,000,000		'	97,000,000
Recurring | Quoted Market Prices in Active Markets (Level 1) | Foreign exchange contracts	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	0		'	0
Derivative instruments, liabilities	'		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Interest-rate contracts	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	0		'	0
Derivative instruments, liabilities	'		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Other	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	0		'	0
Derivative instruments, liabilities	'		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | U.S. government securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	20,000,000		'	20,000,000
Recurring | Quoted Market Prices in Active Markets (Level 1) | Non-U.S. government securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	401,000,000		'	399,000,000
Recurring | Quoted Market Prices in Active Markets (Level 1) | US Treasury and federal agencies, direct obligations	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	1,280,000,000		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | US Treasury and federal agencies, mortgage-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Total asset-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Asset-backed securities, student loans	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Asset-backed securities, credit cards	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Asset-backed securities, sub-prime	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Asset-backed securities, other	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Total non-U.S. debt securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Non-U.S. debt securities, mortgage-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Non-U.S. debt securities, asset-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Non-US debt securities, government securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Non-U.S. debt securities, other	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | State and political subdivisions	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Collateralized mortgage obligations	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Other U.S.debt securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	60,000,000		'	67,000,000
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | U.S. equity securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Non-U.S. equity securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | U.S. money-market mutual funds	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Quoted Market Prices in Active Markets (Level 1) | Non-U.S. money-market mutual funds	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2)	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	408,000,000		'	357,000,000
Investment securities available for sale	91,819,000,000		'	91,629,000,000
Derivative assets	8,370,000,000		'	11,958,000,000
Other assets	0		'	0
Assets, fair value disclosure	100,597,000,000		'	103,944,000,000
Derivative instruments, liabilities	8,104,000,000		'	11,785,000,000
Other liabilities	0		'	0
Liabilities, fair value disclosure	8,104,000,000		'	11,785,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Foreign exchange contracts	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	8,312,000,000		'	11,892,000,000
Derivative instruments, liabilities	7,834,000,000		'	11,454,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Interest-rate contracts	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	56,000,000		'	65,000,000
Derivative instruments, liabilities	269,000,000		'	331,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Other	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	2,000,000		'	1,000,000
Derivative instruments, liabilities	1,000,000		'	0
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | U.S. government securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	0		'	'
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Non-U.S. government securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	0		'	'
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | US Treasury and federal agencies, direct obligations	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	683,000,000		'	709,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | US Treasury and federal agencies, mortgage-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	22,992,000,000		'	22,847,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Total asset-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	22,915,000,000		'	24,040,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Asset-backed securities, student loans	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	13,947,000,000		'	14,119,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Asset-backed securities, credit cards	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	7,237,000,000		'	8,186,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Asset-backed securities, sub-prime	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	1,155,000,000		'	1,203,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Asset-backed securities, other	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	576,000,000		'	532,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Total non-U.S. debt securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	23,792,000,000		'	23,270,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Non-U.S. debt securities, mortgage-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	11,196,000,000		'	10,654,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Non-U.S. debt securities, asset-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	4,382,000,000		'	4,592,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Non-US debt securities, government securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	3,692,000,000		'	3,761,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Non-U.S. debt securities, other	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	4,522,000,000		'	4,263,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | State and political subdivisions	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	10,402,000,000		'	10,220,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Collateralized mortgage obligations	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	5,060,000,000		'	5,107,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Other U.S.debt securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	408,000,000		'	357,000,000
Investment securities available for sale	4,938,000,000		'	4,972,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | U.S. equity securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	36,000,000		'	34,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Non-U.S. equity securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	1,000,000		'	1,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | U.S. money-market mutual funds	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	993,000,000		'	422,000,000
Recurring | Pricing Methods with Significant Observable Market Inputs (Level 2) | Non-U.S. money-market mutual funds	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	7,000,000		'	7,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3)	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	0		'	'
Investment securities available for sale	6,063,000,000		'	7,545,000,000
Derivative assets	6,000,000		'	19,000,000
Other assets	0		'	0
Assets, fair value disclosure	6,069,000,000		'	7,564,000,000
Derivative instruments, liabilities	17,000,000		'	26,000,000
Other liabilities	0		'	0
Liabilities, fair value disclosure	17,000,000		'	26,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Foreign exchange contracts	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	6,000,000		'	19,000,000
Derivative instruments, liabilities	8,000,000		'	17,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Interest-rate contracts	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	0		'	0
Derivative instruments, liabilities	0		'	0
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Other	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	0		'	0
Derivative instruments, liabilities	9,000,000		'	9,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | U.S. government securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	0		'	'
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Non-U.S. government securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	0		'	'
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | US Treasury and federal agencies, direct obligations	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | US Treasury and federal agencies, mortgage-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	100,000,000		'	716,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Total asset-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	4,637,000,000		'	4,979,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Asset-backed securities, student loans	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	333,000,000		'	423,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Asset-backed securities, credit cards	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	24,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Asset-backed securities, sub-prime	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Asset-backed securities, other	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	4,304,000,000		'	4,532,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Total non-U.S. debt securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	1,074,000,000		'	1,637,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Non-U.S. debt securities, mortgage-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	375,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Non-U.S. debt securities, asset-backed securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	612,000,000		'	798,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Non-US debt securities, government securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Non-U.S. debt securities, other	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	462,000,000		'	464,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | State and political subdivisions	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	42,000,000		'	43,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Collateralized mortgage obligations	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	202,000,000		'	162,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Other U.S.debt securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Trading account assets	0		'	'
Investment securities available for sale	8,000,000		'	8,000,000
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | U.S. equity securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Non-U.S. equity securities	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | U.S. money-market mutual funds	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Non-U.S. money-market mutual funds	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Investment securities available for sale	0		'	0
Recurring | Impact of Netting	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	-4,907,000,000	[1]	'	-6,501,000,000
Other assets	0		'	0	[2]
Assets, fair value disclosure	-4,907,000,000	[1]	'	-6,501,000,000	[2]
Derivative instruments, liabilities	-3,809,000,000	[1]	'	-5,552,000,000
Other liabilities	0		'	0	[2]
Liabilities, fair value disclosure	-3,809,000,000	[1]	'	-5,552,000,000	[2]
Recurring | Impact of Netting | Foreign exchange contracts	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	-4,850,000,000		'	-6,442,000,000	[2]
Derivative instruments, liabilities	-3,752,000,000	[1]	'	-5,458,000,000	[2]
Recurring | Impact of Netting | Interest-rate contracts	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	-56,000,000		'	-59,000,000	[2]
Derivative instruments, liabilities	-56,000,000	[1]	'	-94,000,000	[2]
Recurring | Impact of Netting | Other	'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'	'
Derivative assets	-1,000,000		'	0	[2]
Derivative instruments, liabilities	($1,000,000)		'	$0	[2]
[1]	Represents counterparty netting against level-2 financial assets and liabilities, where a legally enforceable master netting agreement exists between State Street and the counterparty. Netting also reflects asset and liability reductions of $1.37 billion and $274 million, respectively, for cash collateral received from and provided to derivative counterparties.
[2]	Represents counterparty netting against level-2 financial assets and liabilities, where a legally enforceable master netting agreement exists between State Street and the counterparty. Netting also reflects asset and liability reductions of $1.93 billion and $979 million, respectively, for cash collateral received from and provided to derivative counterparties.

Fair_Value_Schedule_of_Fair_Va1

Fair Value (Schedule of Fair Value Measurements, Assets, Using Significant Unobservable Inputs) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	$7,564	$6,980
Recorded in Revenue, Assets	7	110
Recorded in Other Comprehensive Income, Assets	-5	32
Purchases, Assets	93	463
Issuances, Assets	0	0
Sales, Assets	-7	-36
Settlements, Assets	366	557
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	-1,217	-424
Fair value as of end of period	6,069	6,568
Change in Unrealized Gains (Losses) Related to Financial Instruments Held as of period end	-7	53
Derivative instruments, assets	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	19	113
Recorded in Revenue, Assets	-11	95
Recorded in Other Comprehensive Income, Assets	0	0
Purchases, Assets	7	53
Issuances, Assets	0	0
Sales, Assets	0	0
Settlements, Assets	9	89
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	0	0
Fair value as of end of period	6	172
Change in Unrealized Gains (Losses) Related to Financial Instruments Held as of period end	-7	53
Foreign exchange contracts	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	19	113
Recorded in Revenue, Assets	-11	95
Recorded in Other Comprehensive Income, Assets	0	0
Purchases, Assets	7	53
Issuances, Assets	0	0
Sales, Assets	0	0
Settlements, Assets	9	89
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	0	0
Fair value as of end of period	6	172
Change in Unrealized Gains (Losses) Related to Financial Instruments Held as of period end	-7	53
Categories of investments, marketable securities, available-for-sale securities	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	7,545	6,867
Recorded in Revenue, Assets	18	15
Recorded in Other Comprehensive Income, Assets	-5	32
Purchases, Assets	86	410
Issuances, Assets	0	0
Sales, Assets	-7	-36
Settlements, Assets	357	468
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	-1,217	-424
Fair value as of end of period	6,063	6,396
Categories of investments, marketable securities, available-for-sale securities | US Treasury and federal agencies, mortgage-backed securities	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	716	825
Recorded in Revenue, Assets	0	0
Recorded in Other Comprehensive Income, Assets	0	0
Purchases, Assets	0	0
Issuances, Assets	0	0
Sales, Assets	0	0
Settlements, Assets	5	27
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	-611	0
Fair value as of end of period	100	798
Categories of investments, marketable securities, available-for-sale securities | Total asset-backed securities	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	4,979	4,649
Recorded in Revenue, Assets	16	13
Recorded in Other Comprehensive Income, Assets	-3	28
Purchases, Assets	6	180
Issuances, Assets	0	0
Sales, Assets	0	-36
Settlements, Assets	282	-377
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	-79	-100
Fair value as of end of period	4,637	4,357
Categories of investments, marketable securities, available-for-sale securities | Asset-backed securities, student loans	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	423	588
Recorded in Revenue, Assets	1	0
Recorded in Other Comprehensive Income, Assets	1	7
Purchases, Assets	0	0
Issuances, Assets	0	0
Sales, Assets	0	-26
Settlements, Assets	13	8
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	-79	-100
Fair value as of end of period	333	461
Categories of investments, marketable securities, available-for-sale securities | Asset-backed securities, credit cards	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	24	67
Recorded in Revenue, Assets	0	0
Recorded in Other Comprehensive Income, Assets	0	0
Purchases, Assets	0	0
Issuances, Assets	0	0
Sales, Assets	0	0
Settlements, Assets	24	43
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	0	0
Fair value as of end of period	0	24
Categories of investments, marketable securities, available-for-sale securities | Asset-backed securities, other	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	4,532	3,994
Recorded in Revenue, Assets	15	13
Recorded in Other Comprehensive Income, Assets	-4	21
Purchases, Assets	6	180
Issuances, Assets	0	0
Sales, Assets	0	-10
Settlements, Assets	245	326
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	0	0
Fair value as of end of period	4,304	3,872
Categories of investments, marketable securities, available-for-sale securities | Total non-U.S. debt securities	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	1,637	1,219
Recorded in Revenue, Assets	2	2
Recorded in Other Comprehensive Income, Assets	-2	3
Purchases, Assets	0	230
Issuances, Assets	0	0
Sales, Assets	-1	0
Settlements, Assets	63	53
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	-499	-324
Fair value as of end of period	1,074	1,077
Categories of investments, marketable securities, available-for-sale securities | Non-U.S. debt securities, mortgage-backed securities	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	375	555
Recorded in Revenue, Assets	0	0
Recorded in Other Comprehensive Income, Assets	0	0
Purchases, Assets	0	0
Issuances, Assets	0	0
Sales, Assets	0	0
Settlements, Assets	0	17
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	-375	-207
Fair value as of end of period	0	331
Categories of investments, marketable securities, available-for-sale securities | Non-U.S. debt securities, asset-backed securities	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	798	524
Recorded in Revenue, Assets	2	2
Recorded in Other Comprehensive Income, Assets	-1	3
Purchases, Assets	0	51
Issuances, Assets	0	0
Sales, Assets	0	0
Settlements, Assets	63	33
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	-124	-77
Fair value as of end of period	612	470
Categories of investments, marketable securities, available-for-sale securities | Non-U.S. debt securities, other	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	464	140
Recorded in Revenue, Assets	0	0
Recorded in Other Comprehensive Income, Assets	-1	0
Purchases, Assets	0	179
Issuances, Assets	0	0
Sales, Assets	-1	0
Settlements, Assets	0	3
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	0	-40
Fair value as of end of period	462	276
Categories of investments, marketable securities, available-for-sale securities | State and political subdivisions	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	43	48
Recorded in Revenue, Assets	0	0
Recorded in Other Comprehensive Income, Assets	0	1
Purchases, Assets	0	0
Issuances, Assets	0	0
Sales, Assets	0	0
Settlements, Assets	-1	2
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	0	0
Fair value as of end of period	42	47
Categories of investments, marketable securities, available-for-sale securities | Collateralized mortgage obligations	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	162	117
Recorded in Revenue, Assets	0	0
Recorded in Other Comprehensive Income, Assets	0	0
Purchases, Assets	80	0
Issuances, Assets	0	0
Sales, Assets	-6	0
Settlements, Assets	-6	9
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	-28	0
Fair value as of end of period	202	108
Categories of investments, marketable securities, available-for-sale securities | Other U.S.debt securities	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair value as of beginning of period	8	9
Recorded in Revenue, Assets	0	0
Recorded in Other Comprehensive Income, Assets	0	0
Purchases, Assets	0	0
Issuances, Assets	0	0
Sales, Assets	0	0
Settlements, Assets	0	0
Transfers into Level 3, Assets	0	0
Transfers out of Level 3, Assets	0	0
Fair value as of end of period	$8	$9

Fair_Value_Schedule_of_Fair_Va2

Fair Value (Schedule of Fair Value Measurements, Liabilities, Using Significant Unobservable Inputs) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair Value, beginning balance, Liabilities	$26,000,000	$115,000,000
Recorded in Revenue, Liabilities	-10,000,000	61,000,000
Recorded in Other Comprehensive Income, Liabilities	0	0
Purchases, Liabilities	0	0
Issuances, Liabilities	7,000,000	50,000,000
Sales, Liabilities	0	0
Settlements, Liabilities	-6,000,000	-64,000,000
Fair Value, ending balance, Liabilities	17,000,000	162,000,000
Change in Unrealized (Gains) Losses Related to Financial Instruments Held as of end of period	-5,000,000	39,000,000
Derivative instruments, liabilities | Accrued expenses and other liabilities	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair Value, beginning balance, Liabilities	26,000,000	115,000,000
Recorded in Revenue, Liabilities	-10,000,000	61,000,000
Recorded in Other Comprehensive Income, Liabilities	0	'
Purchases, Liabilities	0	'
Issuances, Liabilities	7,000,000	50,000,000
Sales, Liabilities	0	'
Settlements, Liabilities	-6,000,000	-64,000,000
Fair Value, ending balance, Liabilities	17,000,000	162,000,000
Change in Unrealized (Gains) Losses Related to Financial Instruments Held as of end of period	-5,000,000	39,000,000
Foreign exchange contracts | Accrued expenses and other liabilities	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair Value, beginning balance, Liabilities	17,000,000	106,000,000
Recorded in Revenue, Liabilities	-10,000,000	61,000,000
Recorded in Other Comprehensive Income, Liabilities	0	0
Purchases, Liabilities	0	0
Issuances, Liabilities	7,000,000	50,000,000
Sales, Liabilities	0	0
Settlements, Liabilities	-6,000,000	-64,000,000
Fair Value, ending balance, Liabilities	8,000,000	153,000,000
Change in Unrealized (Gains) Losses Related to Financial Instruments Held as of end of period	-5,000,000	39,000,000
Other | Accrued expenses and other liabilities	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'
Fair Value, beginning balance, Liabilities	9,000,000	9,000,000
Recorded in Revenue, Liabilities	0	0
Recorded in Other Comprehensive Income, Liabilities	0	0
Purchases, Liabilities	0	0
Issuances, Liabilities	0	0
Sales, Liabilities	0	0
Settlements, Liabilities	0	0
Fair Value, ending balance, Liabilities	9,000,000	9,000,000
Change in Unrealized (Gains) Losses Related to Financial Instruments Held as of end of period	$0	$0

Fair_Value_Level_3_Total_Reali

Fair Value (Level 3 Total Realized And Unrealized Gains And Losses Recorded In Revenue) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Total Revenue [Member]	'	'
Realized and Unrealized Gains and Losses [Line Items]	'	'
Total Realized and Unrealized Gains (Losses) Recorded in Revenue	$17	$49
Change in Unrealized Gains (Losses) Related to Financial Instruments Held	-2	14
Trading services	'	'
Realized and Unrealized Gains and Losses [Line Items]	'	'
Total Realized and Unrealized Gains (Losses) Recorded in Revenue	-1	34
Change in Unrealized Gains (Losses) Related to Financial Instruments Held	-2	14
Total fee revenue	'	'
Realized and Unrealized Gains and Losses [Line Items]	'	'
Total Realized and Unrealized Gains (Losses) Recorded in Revenue	-1	34
Change in Unrealized Gains (Losses) Related to Financial Instruments Held	-2	14
Net interest revenue	'	'
Realized and Unrealized Gains and Losses [Line Items]	'	'
Total Realized and Unrealized Gains (Losses) Recorded in Revenue	18	15
Change in Unrealized Gains (Losses) Related to Financial Instruments Held	$0	$0

Fair_Value_Fair_Value_Inputs_A

Fair Value (Fair Value Inputs, Assets and Liabilities, Quantitative Information) (Details) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2014		Dec. 31, 2013
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	99,162,000,000		99,174,000,000
Asset-backed securities, student loans	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	14,280,000,000	[1]	14,542,000,000	[1]
Asset-backed securities, credit cards	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	7,237,000,000		8,210,000,000
Asset-backed securities, other	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	4,880,000,000		5,064,000,000
Non-U.S. debt securities, other	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	4,984,000,000		4,727,000,000
State and political subdivisions	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	10,444,000,000		10,263,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3)	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Assets, fair value disclosure	6,069,000,000		7,564,000,000
Liabilities, fair value disclosure	17,000,000		26,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Derivative instruments, liabilities	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Derivative instruments, foreign exchange contracts, liabilities	8,000,000		17,000,000
Derivative instruments, other, liabilities	9,000,000		9,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Derivative instruments, assets	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Derivative instruments, foreign exchange contracts, assets	6,000,000		19,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Asset-backed securities, student loans	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	333,000,000		423,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Asset-backed securities, credit cards	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	'		24,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Asset-backed securities, other	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	4,304,000,000		4,532,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Non-U.S. debt securities, other	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	462,000,000		464,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | State and political subdivisions	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	42,000,000		43,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Discounted cash flows | Derivative instruments, liabilities | Weighted average	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Participant redemptions	7.40%	[2]	7.50%	[2]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Discounted cash flows | Asset-backed securities, student loans | Weighted average	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Credit spread	2.90%		3.50%
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Discounted cash flows | Asset-backed securities, credit cards | Weighted average	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Credit spread	0.00%		2.00%
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Discounted cash flows | Asset-backed securities, other | Weighted average	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Credit spread	1.30%		1.50%
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Discounted cash flows | State and political subdivisions | Weighted average	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Credit spread	1.70%		1.70%
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Option model | Derivative instruments, liabilities | Weighted average	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Volatility	'		11.20%
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Option model | Derivative instruments, assets | Weighted average	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Volatility	8.00%		11.40%
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member]	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Assets, fair value disclosure	149,000,000	[3]	191,000,000	[3]
Liabilities, fair value disclosure	17,000,000	[3]	26,000,000	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Derivative instruments, liabilities	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Derivative instruments, foreign exchange contracts, liabilities	8,000,000	[3]	17,000,000	[3]
Derivative instruments, other, liabilities	9,000,000	[3]	9,000,000	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Derivative instruments, assets	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Derivative instruments, foreign exchange contracts, assets	6,000,000	[3]	19,000,000	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Asset-backed securities, student loans	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	14,000,000	[3]	13,000,000	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Asset-backed securities, credit cards	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	0	[3]	24,000,000	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Asset-backed securities, other	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	87,000,000	[3]	92,000,000	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Non-U.S. debt securities, other	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	0	[3]	0	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | State and political subdivisions	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	42,000,000	[3]	43,000,000	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Discounted cash flows | Derivative instruments, liabilities	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Derivative instruments, other, liabilities	9,000,000	[2]	9,000,000	[2]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Discounted cash flows | Asset-backed securities, student loans	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	'		13,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Discounted cash flows | Asset-backed securities, credit cards	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	'		24,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Discounted cash flows | Asset-backed securities, other	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	'		92,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Discounted cash flows | State and political subdivisions	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Investment securities available for sale	'		43,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Option model | Derivative instruments, liabilities	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Derivative instruments, foreign exchange contracts, liabilities	8,000,000		17,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Option model | Derivative instruments, assets	'		'
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]	'		'
Derivative instruments, foreign exchange contracts, assets	6,000,000		19,000,000
[1]	Substantially composed of securities guaranteed by the federal government with respect to at least 97% of defaulted principal and accrued interest on the underlying loans.
[2]	Relates to stable value wrap contracts; refer to the sensitivity discussion following the tables presented below, and to note 7.
[3]	Information with respect to these model-priced financial assets and liabilities is provided above in a separate table.

Fair_Value_Schedule_of_Availab

Fair Value (Schedule of Availability of Significant Unobservable Inputs by Balance Sheet Classification) (Details) (USD $)	Mar. 31, 2014		Dec. 31, 2013
Assets:	'		'
Investment securities available for sale	$99,162,000,000		$99,174,000,000
Asset-backed securities, student loans	'		'
Assets:	'		'
Investment securities available for sale	14,280,000,000	[1]	14,542,000,000	[1]
Asset-backed securities, credit cards	'		'
Assets:	'		'
Investment securities available for sale	7,237,000,000		8,210,000,000
Asset-backed securities, other	'		'
Assets:	'		'
Investment securities available for sale	4,880,000,000		5,064,000,000
Non-U.S. debt securities, mortgage-backed securities	'		'
Assets:	'		'
Investment securities available for sale	11,196,000,000		11,029,000,000
Non-U.S. debt securities, asset-backed securities	'		'
Assets:	'		'
Investment securities available for sale	4,994,000,000		5,390,000,000
Non-U.S. debt securities, other	'		'
Assets:	'		'
Investment securities available for sale	4,984,000,000		4,727,000,000
State and political subdivisions	'		'
Assets:	'		'
Investment securities available for sale	10,444,000,000		10,263,000,000
Collateralized mortgage obligations	'		'
Assets:	'		'
Investment securities available for sale	5,262,000,000		5,269,000,000
Other U.S.debt securities	'		'
Assets:	'		'
Investment securities available for sale	4,946,000,000		4,980,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3)	'		'
Assets:	'		'
Assets, fair value disclosure	6,069,000,000		7,564,000,000
Liabilities:	'		'
Liabilities, fair value disclosure	17,000,000		26,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Derivative instruments, liabilities	'		'
Liabilities:	'		'
Derivative instruments, foreign exchange contracts, liabilities	8,000,000		17,000,000
Derivative instruments, other, liabilities	9,000,000		9,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Derivative instruments, assets	'		'
Assets:	'		'
Derivative instruments, foreign exchange contracts, assets	6,000,000		19,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | U.S. Treasury and federal agencies, mortgage-backed securities	'		'
Assets:	'		'
Investment securities available for sale	100,000,000		716,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Asset-backed securities, student loans	'		'
Assets:	'		'
Investment securities available for sale	333,000,000		423,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Asset-backed securities, credit cards	'		'
Assets:	'		'
Investment securities available for sale	'		24,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Asset-backed securities, other	'		'
Assets:	'		'
Investment securities available for sale	4,304,000,000		4,532,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Non-U.S. debt securities, mortgage-backed securities	'		'
Assets:	'		'
Investment securities available for sale	'		375,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Non-U.S. debt securities, asset-backed securities	'		'
Assets:	'		'
Investment securities available for sale	612,000,000		798,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Non-U.S. debt securities, other	'		'
Assets:	'		'
Investment securities available for sale	462,000,000		464,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | State and political subdivisions	'		'
Assets:	'		'
Investment securities available for sale	42,000,000		43,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Collateralized mortgage obligations	'		'
Assets:	'		'
Investment securities available for sale	202,000,000		162,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Other U.S.debt securities	'		'
Assets:	'		'
Investment securities available for sale	8,000,000		8,000,000
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member]	'		'
Assets:	'		'
Assets, fair value disclosure	149,000,000	[2]	191,000,000	[2]
Liabilities:	'		'
Liabilities, fair value disclosure	17,000,000	[2]	26,000,000	[2]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Derivative instruments, liabilities	'		'
Liabilities:	'		'
Derivative instruments, foreign exchange contracts, liabilities	8,000,000	[2]	17,000,000	[2]
Derivative instruments, other, liabilities	9,000,000	[2]	9,000,000	[2]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Derivative instruments, assets	'		'
Assets:	'		'
Derivative instruments, foreign exchange contracts, assets	6,000,000	[2]	19,000,000	[2]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | U.S. Treasury and federal agencies, mortgage-backed securities	'		'
Assets:	'		'
Investment securities available for sale	0	[2]	0	[2]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Asset-backed securities, student loans	'		'
Assets:	'		'
Investment securities available for sale	14,000,000	[2]	13,000,000	[2]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Asset-backed securities, credit cards	'		'
Assets:	'		'
Investment securities available for sale	0	[2]	24,000,000	[2]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Asset-backed securities, other	'		'
Assets:	'		'
Investment securities available for sale	87,000,000	[2]	92,000,000	[2]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Non-U.S. debt securities, mortgage-backed securities	'		'
Assets:	'		'
Investment securities available for sale	'		0	[2]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Non-U.S. debt securities, asset-backed securities	'		'
Assets:	'		'
Investment securities available for sale	0	[2]	0	[2]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Non-U.S. debt securities, other	'		'
Assets:	'		'
Investment securities available for sale	0	[2]	0	[2]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | State and political subdivisions	'		'
Assets:	'		'
Investment securities available for sale	42,000,000	[2]	43,000,000	[2]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Collateralized mortgage obligations	'		'
Assets:	'		'
Investment securities available for sale	0	[2]	0	[2]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Readily Available [Member] | Other U.S.debt securities	'		'
Assets:	'		'
Investment securities available for sale	0	[2]	0	[2]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Not Readily Available [Member]	'		'
Assets:	'		'
Assets, fair value disclosure	5,920,000,000	[3]	7,373,000,000	[3]
Liabilities:	'		'
Liabilities, fair value disclosure	0	[3]	0	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Not Readily Available [Member] | Derivative instruments, liabilities	'		'
Liabilities:	'		'
Derivative instruments, foreign exchange contracts, liabilities	0	[3]	0	[3]
Derivative instruments, other, liabilities	0	[3]	0	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Not Readily Available [Member] | Derivative instruments, assets	'		'
Assets:	'		'
Derivative instruments, foreign exchange contracts, assets	0	[3]	0	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Not Readily Available [Member] | U.S. Treasury and federal agencies, mortgage-backed securities	'		'
Assets:	'		'
Investment securities available for sale	100,000,000	[3]	716,000,000	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Not Readily Available [Member] | Asset-backed securities, student loans	'		'
Assets:	'		'
Investment securities available for sale	319,000,000	[3]	410,000,000	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Not Readily Available [Member] | Asset-backed securities, credit cards	'		'
Assets:	'		'
Investment securities available for sale	'		0	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Not Readily Available [Member] | Asset-backed securities, other	'		'
Assets:	'		'
Investment securities available for sale	4,217,000,000	[3]	4,440,000,000	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Not Readily Available [Member] | Non-U.S. debt securities, mortgage-backed securities	'		'
Assets:	'		'
Investment securities available for sale	'		375,000,000	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Not Readily Available [Member] | Non-U.S. debt securities, asset-backed securities	'		'
Assets:	'		'
Investment securities available for sale	612,000,000	[3]	798,000,000	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Not Readily Available [Member] | Non-U.S. debt securities, other	'		'
Assets:	'		'
Investment securities available for sale	462,000,000	[3]	464,000,000	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Not Readily Available [Member] | State and political subdivisions	'		'
Assets:	'		'
Investment securities available for sale	0	[3]	0	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Not Readily Available [Member] | Collateralized mortgage obligations	'		'
Assets:	'		'
Investment securities available for sale	202,000,000	[3]	162,000,000	[3]
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Significant Unobservable Inputs Not Readily Available [Member] | Other U.S.debt securities	'		'
Assets:	'		'
Investment securities available for sale	$8,000,000	[3]	$8,000,000	[3]
[1]	Substantially composed of securities guaranteed by the federal government with respect to at least 97% of defaulted principal and accrued interest on the underlying loans.
[2]	Information with respect to these model-priced financial assets and liabilities is provided above in a separate table.
[3]	Fair value for these financial assets is measured using non-binding broker or dealer quotes.

Fair_Value_Carrying_Value_and_

Fair Value (Carrying Value and Estimated Fair Value of Financial Instruments) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Financial Assets:	'	'	'	'
Cash and due from banks	$3,877	$3,220	$4,708	$2,590
Interest-bearing deposits with banks	75,796	64,257	'	'
Securities purchased under resale agreements	6,087	6,230	'	'
Investment securities held to maturity	18,342	17,740	'	'
Financial Liabilities:	'	'	'	'
Noninterest-bearing	72,800	65,614	'	'
Interest-bearingbU.S.	15,327	13,392	'	'
Interest-bearingbnon-U.S.	106,521	103,262	'	'
Securities sold under repurchase agreements	8,953	7,953	'	'
Federal funds purchased	18	19	'	'
Other short-term borrowings	3,811	3,780	'	'
Long-term debt	9,503	9,699	'	'
Reported Amount	'	'	'	'
Financial Assets:	'	'	'	'
Cash and due from banks	3,877	3,220	'	'
Interest-bearing deposits with banks	75,796	64,257	'	'
Securities purchased under resale agreements	6,087	6,230	'	'
Investment securities held to maturity	18,342	17,740	'	'
Net loans (excluding leases)	14,994	12,363	'	'
Financial Liabilities:	'	'	'	'
Noninterest-bearing	72,800	65,614	'	'
Interest-bearingbU.S.	15,327	13,392	'	'
Interest-bearingbnon-U.S.	106,521	103,262	'	'
Securities sold under repurchase agreements	8,953	7,953	'	'
Federal funds purchased	18	19	'	'
Other short-term borrowings	3,811	3,780	'	'
Long-term debt	9,503	9,699	'	'
Estimated Fair Value	'	'	'	'
Financial Assets:	'	'	'	'
Cash and due from banks	3,877	3,220	'	'
Interest-bearing deposits with banks	75,796	64,257	'	'
Securities purchased under resale agreements	6,087	6,230	'	'
Investment securities held to maturity	18,326	17,560	'	'
Net loans (excluding leases)	15,002	12,355	'	'
Financial Liabilities:	'	'	'	'
Noninterest-bearing	72,800	65,614	'	'
Interest-bearingbU.S.	15,327	13,392	'	'
Interest-bearingbnon-U.S.	106,521	103,262	'	'
Securities sold under repurchase agreements	8,953	7,953	'	'
Federal funds purchased	18	19	'	'
Other short-term borrowings	3,811	3,780	'	'
Long-term debt	9,809	9,909	'	'
Quoted Market Prices in Active Markets (Level 1) | Estimated Fair Value	'	'	'	'
Financial Assets:	'	'	'	'
Cash and due from banks	3,877	3,220	'	'
Interest-bearing deposits with banks	0	0	'	'
Securities purchased under resale agreements	0	0	'	'
Investment securities held to maturity	0	0	'	'
Net loans (excluding leases)	0	0	'	'
Financial Liabilities:	'	'	'	'
Noninterest-bearing	0	0	'	'
Interest-bearingbU.S.	0	0	'	'
Interest-bearingbnon-U.S.	0	0	'	'
Securities sold under repurchase agreements	0	0	'	'
Federal funds purchased	0	0	'	'
Other short-term borrowings	0	0	'	'
Long-term debt	0	0	'	'
Pricing Methods with Significant Observable Market Inputs (Level 2) | Estimated Fair Value	'	'	'	'
Financial Assets:	'	'	'	'
Cash and due from banks	0	0	'	'
Interest-bearing deposits with banks	75,796	64,257	'	'
Securities purchased under resale agreements	6,087	6,230	'	'
Investment securities held to maturity	18,326	17,560	'	'
Net loans (excluding leases)	'	11,908	'	'
Financial Liabilities:	'	'	'	'
Noninterest-bearing	72,800	65,614	'	'
Interest-bearingbU.S.	15,327	13,392	'	'
Interest-bearingbnon-U.S.	106,521	103,262	'	'
Securities sold under repurchase agreements	8,953	7,953	'	'
Federal funds purchased	18	19	'	'
Other short-term borrowings	3,811	3,780	'	'
Long-term debt	8,927	9,056	'	'
Pricing Methods with Significant Unobservable Market Inputs (Level 3) | Estimated Fair Value	'	'	'	'
Financial Assets:	'	'	'	'
Cash and due from banks	0	0	'	'
Interest-bearing deposits with banks	0	0	'	'
Securities purchased under resale agreements	0	0	'	'
Investment securities held to maturity	0	0	'	'
Net loans (excluding leases)	472	447	'	'
Financial Liabilities:	'	'	'	'
Noninterest-bearing	0	0	'	'
Interest-bearingbU.S.	0	0	'	'
Interest-bearingbnon-U.S.	0	0	'	'
Securities sold under repurchase agreements	0	0	'	'
Federal funds purchased	0	0	'	'
Other short-term borrowings	0	0	'	'
Long-term debt	$882	$853	'	'

Investment_Securities_Narrativ

Investment Securities (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
	security
	country
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'	'	'
Pledged Financial Instruments, Not Separately Reported, Securities	$47,670,000,000	'	$46,990,000,000
Other-than-temporary impairment recorded	9,000,000	3,000,000	'
Number of peripheral european countries	4	'	'
Impairment associated with adverse changes in timing of expected future cash flows	0	3,000,000	'
Gross pre-tax unrealized losses on securities	1,240,000,000	'	'
Number of available for sale and held to maturity securities in gross pre-tax unrealized loss position	2,122	'	'
Minimum	'	'	'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'	'	'
Percentage change in additional house price declines	10.00%	'	'
Maximum	'	'	'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'	'	'
Percentage change in additional house price declines	19.00%	'	'
Federal Family Education Loan Program	'	'	'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'	'	'
Federal government credit support guarantee, percentage minimum	97.00%	'	'
Other-than-temporary impairment recorded	0	'	'
Collective credit support, percentage minimum	100.00%	'	'
Average remaining term	'4 years 9 months 18 days	'	'
Maximum concentration risk on credit instruments (less than)	800,000,000	'	'
U.S. agency residential mortgage-backed securities	'	'	'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'	'	'
Other-than-temporary impairment recorded	0	0	'
Non-U.S. debt securities, mortgage-backed securities	'	'	'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'	'	'
Other-than-temporary impairment recorded	'	3,000,000	'
Non-U.S. debt securities, mortgage-backed securities | European Periphery	'	'	'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'	'	'
Total exposure to asset backed securities	647,000,000	'	'
Aggregate pre-tax gross unrealized gain (loss) on available for sale securities	91,000,000	'	'
Available for sale, gross unrealized gains	96,000,000	'	'
Available for sale, gross unrealized losses	-5,000,000	'	'
Non-U.S. debt securities, mortgage-backed securities | Spain	'	'	'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'	'	'
Total exposure to asset backed securities	204,000,000	'	'
Non-U.S. debt securities, mortgage-backed securities | Italy	'	'	'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'	'	'
Total exposure to asset backed securities	243,000,000	'	'
Non-U.S. debt securities, mortgage-backed securities | Ireland	'	'	'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'	'	'
Total exposure to asset backed securities	120,000,000	'	'
Non-U.S. debt securities, mortgage-backed securities | Portugal	'	'	'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'	'	'
Total exposure to asset backed securities	80,000,000	'	'
Asset-backed securities, student loans	'	'	'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'	'	'
Other-than-temporary impairment recorded	0	0	'
Direct sovereign debt	'	'	'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'	'	'
Total exposure to asset backed securities	0	'	'
State and political subdivisions	'	'	'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'	'	'
Other-than-temporary impairment recorded	0	0	'
Collateralized mortgage obligations	'	'	'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'	'	'
Other-than-temporary impairment recorded	$9,000,000	$0	'

Investment_Securities_Schedule

Investment Securities (Schedule of Marketable Securities) (Details) (USD $)	Mar. 31, 2014		Dec. 31, 2013
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	$98,770,000,000		$99,159,000,000
Available for sale, gross unrealized gains	1,243,000,000		1,162,000,000
Available for sale, gross unrealized losses	851,000,000		1,147,000,000
Available for sale, fair value	99,162,000,000		99,174,000,000
Held to maturity, amortized cost	18,342,000,000		17,740,000,000
Held to maturity, gross unrealized gains	369,000,000		354,000,000
Held to maturity, gross unrealized losses	385,000,000		534,000,000
Held to maturity, fair value	18,326,000,000		17,560,000,000
Total asset-backed securities	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	27,609,000,000		29,188,000,000
Available for sale, gross unrealized gains	285,000,000		254,000,000
Available for sale, gross unrealized losses	342,000,000		423,000,000
Available for sale, fair value	27,552,000,000		29,019,000,000
Held to maturity, amortized cost	3,524,000,000		3,171,000,000
Held to maturity, gross unrealized gains	9,000,000		2,000,000
Held to maturity, gross unrealized losses	3,000,000		12,000,000
Held to maturity, fair value	3,530,000,000		3,161,000,000
US Treasury and federal agencies, direct obligations	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	1,959,000,000		702,000,000
Available for sale, gross unrealized gains	10,000,000		9,000,000
Available for sale, gross unrealized losses	6,000,000		2,000,000
Available for sale, fair value	1,963,000,000		709,000,000
Held to maturity, amortized cost	5,096,000,000		5,041,000,000
Held to maturity, gross unrealized gains	0		0
Held to maturity, gross unrealized losses	328,000,000		448,000,000
Held to maturity, fair value	4,768,000,000		4,593,000,000
US Treasury and federal agencies, mortgage-backed securities	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	23,176,000,000		23,744,000,000
Available for sale, gross unrealized gains	206,000,000		211,000,000
Available for sale, gross unrealized losses	290,000,000		392,000,000
Available for sale, fair value	23,092,000,000		23,563,000,000
Held to maturity, amortized cost	81,000,000		91,000,000
Held to maturity, gross unrealized gains	6,000,000		6,000,000
Held to maturity, gross unrealized losses	0		0
Held to maturity, fair value	87,000,000		97,000,000
Asset-backed securities, student loans	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	14,355,000,000	[1]	14,718,000,000	[1]
Available for sale, gross unrealized gains	128,000,000	[1]	92,000,000	[1]
Available for sale, gross unrealized losses	203,000,000	[1]	268,000,000	[1]
Available for sale, fair value	14,280,000,000	[1]	14,542,000,000	[1]
Held to maturity, amortized cost	1,889,000,000	[1]	1,627,000,000	[1]
Held to maturity, gross unrealized gains	5,000,000	[1]	0	[1]
Held to maturity, gross unrealized losses	2,000,000	[1]	10,000,000	[1]
Held to maturity, fair value	1,892,000,000	[1]	1,617,000,000	[1]
Asset-backed securities, credit cards	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	7,253,000,000		8,230,000,000
Available for sale, gross unrealized gains	21,000,000		21,000,000
Available for sale, gross unrealized losses	37,000,000		41,000,000
Available for sale, fair value	7,237,000,000		8,210,000,000
Held to maturity, amortized cost	897,000,000		762,000,000
Held to maturity, gross unrealized gains	3,000,000		1,000,000
Held to maturity, gross unrealized losses	0		0
Held to maturity, fair value	900,000,000		763,000,000
Asset-backed securities, sub-prime	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	1,234,000,000		1,291,000,000
Available for sale, gross unrealized gains	3,000,000		3,000,000
Available for sale, gross unrealized losses	82,000,000		91,000,000
Available for sale, fair value	1,155,000,000		1,203,000,000
Asset-backed securities, other	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	4,767,000,000		4,949,000,000
Available for sale, gross unrealized gains	133,000,000		138,000,000
Available for sale, gross unrealized losses	20,000,000		23,000,000
Available for sale, fair value	4,880,000,000		5,064,000,000
Held to maturity, amortized cost	738,000,000		782,000,000
Held to maturity, gross unrealized gains	1,000,000		1,000,000
Held to maturity, gross unrealized losses	1,000,000		2,000,000
Held to maturity, fair value	738,000,000		781,000,000
Total non-U.S. debt securities	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	24,571,000,000		24,615,000,000
Available for sale, gross unrealized gains	313,000,000		314,000,000
Available for sale, gross unrealized losses	18,000,000		22,000,000
Available for sale, fair value	24,866,000,000		24,907,000,000
Held to maturity, amortized cost	6,916,000,000		6,607,000,000
Held to maturity, gross unrealized gains	191,000,000		169,000,000
Held to maturity, gross unrealized losses	29,000,000		48,000,000
Held to maturity, fair value	7,078,000,000		6,728,000,000
Non-U.S. debt securities, mortgage-backed securities	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	10,978,000,000		10,808,000,000
Available for sale, gross unrealized gains	225,000,000		230,000,000
Available for sale, gross unrealized losses	7,000,000		9,000,000
Available for sale, fair value	11,196,000,000		11,029,000,000
Held to maturity, amortized cost	4,323,000,000		4,211,000,000
Held to maturity, gross unrealized gains	172,000,000		150,000,000
Held to maturity, gross unrealized losses	29,000,000		48,000,000
Held to maturity, fair value	4,466,000,000		4,313,000,000
Non-U.S. debt securities, asset-backed securities	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	4,973,000,000		5,369,000,000
Available for sale, gross unrealized gains	23,000,000		23,000,000
Available for sale, gross unrealized losses	2,000,000		2,000,000
Available for sale, fair value	4,994,000,000		5,390,000,000
Held to maturity, amortized cost	2,399,000,000		2,202,000,000
Held to maturity, gross unrealized gains	19,000,000		19,000,000
Held to maturity, gross unrealized losses	0		0
Held to maturity, fair value	2,418,000,000		2,221,000,000
Non-US debt securities, government securities	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	3,689,000,000		3,759,000,000
Available for sale, gross unrealized gains	3,000,000		2,000,000
Available for sale, gross unrealized losses	0		0
Available for sale, fair value	3,692,000,000		3,761,000,000
Held to maturity, amortized cost	2,000,000		2,000,000
Held to maturity, gross unrealized gains	0		0
Held to maturity, gross unrealized losses	0		0
Held to maturity, fair value	2,000,000		2,000,000
Non-U.S. debt securities, other	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	4,931,000,000		4,679,000,000
Available for sale, gross unrealized gains	62,000,000		59,000,000
Available for sale, gross unrealized losses	9,000,000		11,000,000
Available for sale, fair value	4,984,000,000		4,727,000,000
Held to maturity, amortized cost	192,000,000		192,000,000
Held to maturity, gross unrealized gains	0		0
Held to maturity, gross unrealized losses	0		0
Held to maturity, fair value	192,000,000		192,000,000
State and political subdivisions	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	10,345,000,000		10,301,000,000
Available for sale, gross unrealized gains	216,000,000		160,000,000
Available for sale, gross unrealized losses	117,000,000		198,000,000
Available for sale, fair value	10,444,000,000		10,263,000,000
Held to maturity, amortized cost	16,000,000		24,000,000
Held to maturity, gross unrealized gains	0		1,000,000
Held to maturity, gross unrealized losses	0		0
Held to maturity, fair value	16,000,000		25,000,000
Collateralized mortgage obligations	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	5,253,000,000		5,275,000,000
Available for sale, gross unrealized gains	67,000,000		70,000,000
Available for sale, gross unrealized losses	58,000,000		76,000,000
Available for sale, fair value	5,262,000,000		5,269,000,000
Held to maturity, amortized cost	2,709,000,000		2,806,000,000
Held to maturity, gross unrealized gains	163,000,000		176,000,000
Held to maturity, gross unrealized losses	25,000,000		26,000,000
Held to maturity, fair value	2,847,000,000		2,956,000,000
Other U.S.debt securities	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	4,827,000,000		4,876,000,000
Available for sale, gross unrealized gains	139,000,000		138,000,000
Available for sale, gross unrealized losses	20,000,000		34,000,000
Available for sale, fair value	4,946,000,000		4,980,000,000
U.S. equity securities	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	29,000,000		28,000,000
Available for sale, gross unrealized gains	7,000,000		6,000,000
Available for sale, gross unrealized losses	0		0
Available for sale, fair value	36,000,000		34,000,000
Non-U.S. equity securities	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	1,000,000		1,000,000
Available for sale, gross unrealized gains	0		0
Available for sale, gross unrealized losses	0		0
Available for sale, fair value	1,000,000		1,000,000
U.S. money-market mutual funds	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	993,000,000		422,000,000
Available for sale, gross unrealized gains	0		0
Available for sale, gross unrealized losses	0		0
Available for sale, fair value	993,000,000		422,000,000
Non-U.S. money-market mutual funds	'		'
Available-For-Sale and Held-To-Maturity-Securities [Line Items]	'		'
Available for sale, amortized cost	7,000,000		7,000,000
Available for sale, gross unrealized gains	0		0
Available for sale, gross unrealized losses	0		0
Available for sale, fair value	$7,000,000		$7,000,000
[1]	Substantially composed of securities guaranteed by the federal government with respect to at least 97% of defaulted principal and accrued interest on the underlying loans.

Investment_Securities_Schedule1

Investment Securities (Schedule of Gross Pre-Tax Unrealized Losses on Investment Securities) (Details) (USD $)	3 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]	'	'	'
Available for sale, Fair Value Less than 12 months	$23,650	$27,220	'
Available for sale, Gross Unrealized Losses Less than 12 months	348	580	'
Available for sale, Fair Value 12 months or longer	14,768	13,764	'
Available for sale, Gross Unrealized Losses 12 months or longer	503	567	'
Available for sale, Fair Value Total	38,418	40,984	'
Available for sale, Gross Unrealized Losses Total	851	1,147	'
Held to maturity, Fair Value Less than 12 months	6,678	7,813	'
Held to maturity, Gross Unrealized Losses Less than 12 months	343	480	'
Held to maturity, Fair Value 12 months or longer	1,408	1,068	'
Held to maturity, Gross Unrealized Losses 12 months or longer	42	54	'
Held to maturity, Fair Value Total	8,086	8,881	'
Held to maturity, Gross Unrealized Losses Total	385	534	'
Asset-backed securities	'	'	'
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]	'	'	'
Available for sale, Fair Value Less than 12 months	5,914	7,540	'
Available for sale, Gross Unrealized Losses Less than 12 months	41	58	'
Available for sale, Fair Value 12 months or longer	9,009	9,002	'
Available for sale, Gross Unrealized Losses 12 months or longer	301	365	'
Available for sale, Fair Value Total	14,923	16,542	'
Available for sale, Gross Unrealized Losses Total	342	423	'
Held to maturity, Fair Value Less than 12 months	426	1,649	'
Held to maturity, Gross Unrealized Losses Less than 12 months	2	11	'
Held to maturity, Fair Value 12 months or longer	176	29	'
Held to maturity, Gross Unrealized Losses 12 months or longer	1	1	'
Held to maturity, Fair Value Total	602	1,678	'
Held to maturity, Gross Unrealized Losses Total	3	12	'
US Treasury and federal agencies, direct obligations	'	'	'
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]	'	'	'
Available for sale, Fair Value Less than 12 months	1,433	182	'
Available for sale, Gross Unrealized Losses Less than 12 months	5	1	'
Available for sale, Fair Value 12 months or longer	130	113	'
Available for sale, Gross Unrealized Losses 12 months or longer	1	1	'
Available for sale, Fair Value Total	1,563	295	'
Available for sale, Gross Unrealized Losses Total	6	2	'
Held to maturity, Fair Value Less than 12 months	4,751	4,571	'
Held to maturity, Gross Unrealized Losses Less than 12 months	328	448	'
Held to maturity, Fair Value 12 months or longer	0	0	'
Held to maturity, Gross Unrealized Losses 12 months or longer	0	0	'
Held to maturity, Fair Value Total	4,751	4,571	'
Held to maturity, Gross Unrealized Losses Total	328	448	'
US Treasury and federal agencies, mortgage-backed securities	'	'	'
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]	'	'	'
Available for sale, Fair Value Less than 12 months	9,475	10,562	'
Available for sale, Gross Unrealized Losses Less than 12 months	197	316	'
Available for sale, Fair Value 12 months or longer	3,161	2,389	'
Available for sale, Gross Unrealized Losses 12 months or longer	93	76	'
Available for sale, Fair Value Total	12,636	12,951	'
Available for sale, Gross Unrealized Losses Total	290	392	'
Asset-backed securities, student loans	'	'	'
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]	'	'	'
Available for sale, Fair Value Less than 12 months	606	1,930	'
Available for sale, Gross Unrealized Losses Less than 12 months	5	16	'
Available for sale, Fair Value 12 months or longer	7,271	7,252	'
Available for sale, Gross Unrealized Losses 12 months or longer	198	252	'
Available for sale, Fair Value Total	7,877	9,182	'
Available for sale, Gross Unrealized Losses Total	203	268	'
Held to maturity, Fair Value Less than 12 months	297	'	1,352
Held to maturity, Gross Unrealized Losses Less than 12 months	1	10	'
Held to maturity, Fair Value 12 months or longer	176	'	0
Held to maturity, Gross Unrealized Losses 12 months or longer	1	0	'
Held to maturity, Fair Value Total	473	'	1,352
Held to maturity, Gross Unrealized Losses Total	2	10	'
Asset-backed securities, credit cards	'	'	'
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]	'	'	'
Available for sale, Fair Value Less than 12 months	3,311	3,714	'
Available for sale, Gross Unrealized Losses Less than 12 months	26	30	'
Available for sale, Fair Value 12 months or longer	214	161	'
Available for sale, Gross Unrealized Losses 12 months or longer	11	11	'
Available for sale, Fair Value Total	3,525	3,875	'
Available for sale, Gross Unrealized Losses Total	37	41	'
Held to maturity, Fair Value Less than 12 months	'	'	297
Held to maturity, Gross Unrealized Losses Less than 12 months	'	1	'
Held to maturity, Fair Value 12 months or longer	'	'	29
Held to maturity, Gross Unrealized Losses 12 months or longer	'	1	'
Held to maturity, Fair Value Total	'	'	326
Held to maturity, Gross Unrealized Losses Total	'	2	'
Asset-backed securities, sub-prime	'	'	'
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]	'	'	'
Available for sale, Fair Value Less than 12 months	0	0	'
Available for sale, Gross Unrealized Losses Less than 12 months	0	0	'
Available for sale, Fair Value 12 months or longer	1,106	1,150	'
Available for sale, Gross Unrealized Losses 12 months or longer	82	91	'
Available for sale, Fair Value Total	1,106	1,150	'
Available for sale, Gross Unrealized Losses Total	82	91	'
Asset-backed securities, other	'	'	'
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]	'	'	'
Available for sale, Fair Value Less than 12 months	1,997	1,896	'
Available for sale, Gross Unrealized Losses Less than 12 months	10	12	'
Available for sale, Fair Value 12 months or longer	418	439	'
Available for sale, Gross Unrealized Losses 12 months or longer	10	11	'
Available for sale, Fair Value Total	2,415	2,335	'
Available for sale, Gross Unrealized Losses Total	20	23	'
Held to maturity, Fair Value Less than 12 months	129	'	'
Held to maturity, Gross Unrealized Losses Less than 12 months	1	'	'
Held to maturity, Fair Value 12 months or longer	0	'	'
Held to maturity, Gross Unrealized Losses 12 months or longer	0	'	'
Held to maturity, Fair Value Total	129	'	'
Held to maturity, Gross Unrealized Losses Total	1	'	'
Total non-U.S. debt securities	'	'	'
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]	'	'	'
Available for sale, Fair Value Less than 12 months	2,751	3,074	'
Available for sale, Gross Unrealized Losses Less than 12 months	9	12	'
Available for sale, Fair Value 12 months or longer	546	424	'
Available for sale, Gross Unrealized Losses 12 months or longer	9	10	'
Available for sale, Fair Value Total	3,297	3,498	'
Available for sale, Gross Unrealized Losses Total	18	22	'
Held to maturity, Fair Value Less than 12 months	'	834	'
Held to maturity, Gross Unrealized Losses Less than 12 months	'	3	'
Held to maturity, Fair Value 12 months or longer	'	878	'
Held to maturity, Gross Unrealized Losses 12 months or longer	'	45	'
Held to maturity, Fair Value Total	'	1,712	'
Held to maturity, Gross Unrealized Losses Total	'	48	'
Non-U.S. debt securities, mortgage-backed securities	'	'	'
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]	'	'	'
Available for sale, Fair Value Less than 12 months	819	868	'
Available for sale, Gross Unrealized Losses Less than 12 months	2	2	'
Available for sale, Fair Value 12 months or longer	326	258	'
Available for sale, Gross Unrealized Losses 12 months or longer	5	7	'
Available for sale, Fair Value Total	1,145	1,126	'
Available for sale, Gross Unrealized Losses Total	7	9	'
Held to maturity, Fair Value Less than 12 months	906	'	'
Held to maturity, Gross Unrealized Losses Less than 12 months	2	'	'
Held to maturity, Fair Value 12 months or longer	825	'	'
Held to maturity, Gross Unrealized Losses 12 months or longer	27	'	'
Held to maturity, Fair Value Total	1,731	'	'
Held to maturity, Gross Unrealized Losses Total	29	'	'
Non-U.S. debt securities, asset-backed securities	'	'	'
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]	'	'	'
Available for sale, Fair Value Less than 12 months	280	551	'
Available for sale, Gross Unrealized Losses Less than 12 months	1	1	'
Available for sale, Fair Value 12 months or longer	71	16	'
Available for sale, Gross Unrealized Losses 12 months or longer	1	1	'
Available for sale, Fair Value Total	351	567	'
Available for sale, Gross Unrealized Losses Total	2	2	'
Non-U.S. debt securities, other	'	'	'
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]	'	'	'
Available for sale, Fair Value Less than 12 months	1,652	1,655	'
Available for sale, Gross Unrealized Losses Less than 12 months	6	9	'
Available for sale, Fair Value 12 months or longer	149	150	'
Available for sale, Gross Unrealized Losses 12 months or longer	3	2	'
Available for sale, Fair Value Total	1,801	1,805	'
Available for sale, Gross Unrealized Losses Total	9	11	'
State and political subdivisions	'	'	'
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]	'	'	'
Available for sale, Fair Value Less than 12 months	1,850	3,242	'
Available for sale, Gross Unrealized Losses Less than 12 months	49	113	'
Available for sale, Fair Value 12 months or longer	1,311	1,268	'
Available for sale, Gross Unrealized Losses 12 months or longer	68	85	'
Available for sale, Fair Value Total	3,161	4,510	'
Available for sale, Gross Unrealized Losses Total	117	198	'
Collateralized mortgage obligations	'	'	'
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]	'	'	'
Available for sale, Fair Value Less than 12 months	1,444	1,581	'
Available for sale, Gross Unrealized Losses Less than 12 months	34	55	'
Available for sale, Fair Value 12 months or longer	551	510	'
Available for sale, Gross Unrealized Losses 12 months or longer	24	21	'
Available for sale, Fair Value Total	1,995	2,091	'
Available for sale, Gross Unrealized Losses Total	58	76	'
Held to maturity, Fair Value Less than 12 months	595	759	'
Held to maturity, Gross Unrealized Losses Less than 12 months	11	18	'
Held to maturity, Fair Value 12 months or longer	407	161	'
Held to maturity, Gross Unrealized Losses 12 months or longer	14	8	'
Held to maturity, Fair Value Total	1,002	920	'
Held to maturity, Gross Unrealized Losses Total	25	26	'
Other U.S.debt securities	'	'	'
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]	'	'	'
Available for sale, Fair Value Less than 12 months	783	1,039	'
Available for sale, Gross Unrealized Losses Less than 12 months	13	25	'
Available for sale, Fair Value 12 months or longer	60	58	'
Available for sale, Gross Unrealized Losses 12 months or longer	7	9	'
Available for sale, Fair Value Total	843	1,097	'
Available for sale, Gross Unrealized Losses Total	$20	$34	'

Investment_Securities_Schedule2

Investment Securities (Schedule of Contractual Maturities of Debt Securities) (Details) (USD $)	Mar. 31, 2014
In Millions, unless otherwise specified
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	$11,305
Available for sale, 1 to 5 Years	35,501
Available for sale, 6 to 10 Years	21,072
Available for sale, Over 10 Years	30,247
Held to maturity, Under 1 Year	554
Held to maturity, 1 to 5 Years	5,257
Held to maturity, 6 to 10 Years	7,158
Held to maturity, Over 10 Years	5,373
Total asset-backed securities	'
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	3,310
Available for sale, 1 to 5 Years	10,999
Available for sale, 6 to 10 Years	7,591
Available for sale, Over 10 Years	5,652
Held to maturity, Under 1 Year	42
Held to maturity, 1 to 5 Years	974
Held to maturity, 6 to 10 Years	1,208
Held to maturity, Over 10 Years	1,300
US Treasury and federal agencies, direct obligations	'
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	2
Available for sale, 1 to 5 Years	526
Available for sale, 6 to 10 Years	835
Available for sale, Over 10 Years	600
Held to maturity, Under 1 Year	0
Held to maturity, 1 to 5 Years	0
Held to maturity, 6 to 10 Years	5,000
Held to maturity, Over 10 Years	96
US Treasury and federal agencies, mortgage-backed securities	'
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	183
Available for sale, 1 to 5 Years	2,387
Available for sale, 6 to 10 Years	5,276
Available for sale, Over 10 Years	15,246
Held to maturity, Under 1 Year	0
Held to maturity, 1 to 5 Years	19
Held to maturity, 6 to 10 Years	16
Held to maturity, Over 10 Years	46
Asset-backed securities, student loans	'
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	647
Available for sale, 1 to 5 Years	6,608
Available for sale, 6 to 10 Years	4,216
Available for sale, Over 10 Years	2,809
Held to maturity, Under 1 Year	19
Held to maturity, 1 to 5 Years	192
Held to maturity, 6 to 10 Years	383
Held to maturity, Over 10 Years	1,295
Asset-backed securities, credit cards	'
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	2,187
Available for sale, 1 to 5 Years	3,057
Available for sale, 6 to 10 Years	1,993
Available for sale, Over 10 Years	0
Held to maturity, Under 1 Year	0
Held to maturity, 1 to 5 Years	335
Held to maturity, 6 to 10 Years	562
Held to maturity, Over 10 Years	0
Asset-backed securities, sub-prime	'
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	7
Available for sale, 1 to 5 Years	20
Available for sale, 6 to 10 Years	1
Available for sale, Over 10 Years	1,127
Asset-backed securities, other	'
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	469
Available for sale, 1 to 5 Years	1,314
Available for sale, 6 to 10 Years	1,381
Available for sale, Over 10 Years	1,716
Held to maturity, Under 1 Year	23
Held to maturity, 1 to 5 Years	447
Held to maturity, 6 to 10 Years	263
Held to maturity, Over 10 Years	5
Total non-U.S. debt securities	'
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	6,248
Available for sale, 1 to 5 Years	13,248
Available for sale, 6 to 10 Years	1,547
Available for sale, Over 10 Years	3,823
Held to maturity, Under 1 Year	261
Held to maturity, 1 to 5 Years	3,301
Held to maturity, 6 to 10 Years	438
Held to maturity, Over 10 Years	2,916
Non-U.S. debt securities, mortgage-backed securities	'
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	1,698
Available for sale, 1 to 5 Years	5,562
Available for sale, 6 to 10 Years	247
Available for sale, Over 10 Years	3,689
Held to maturity, Under 1 Year	23
Held to maturity, 1 to 5 Years	1,191
Held to maturity, 6 to 10 Years	194
Held to maturity, Over 10 Years	2,915
Non-U.S. debt securities, asset-backed securities	'
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	355
Available for sale, 1 to 5 Years	3,906
Available for sale, 6 to 10 Years	599
Available for sale, Over 10 Years	134
Held to maturity, Under 1 Year	70
Held to maturity, 1 to 5 Years	2,085
Held to maturity, 6 to 10 Years	244
Held to maturity, Over 10 Years	0
Non-US debt securities, government securities	'
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	2,537
Available for sale, 1 to 5 Years	1,155
Available for sale, 6 to 10 Years	0
Available for sale, Over 10 Years	0
Held to maturity, Under 1 Year	2
Held to maturity, 1 to 5 Years	0
Held to maturity, 6 to 10 Years	0
Held to maturity, Over 10 Years	0
Non-U.S. debt securities, other	'
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	1,658
Available for sale, 1 to 5 Years	2,625
Available for sale, 6 to 10 Years	701
Available for sale, Over 10 Years	0
Held to maturity, Under 1 Year	166
Held to maturity, 1 to 5 Years	25
Held to maturity, 6 to 10 Years	0
Held to maturity, Over 10 Years	1
State and political subdivisions	'
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	672
Available for sale, 1 to 5 Years	3,122
Available for sale, 6 to 10 Years	4,049
Available for sale, Over 10 Years	2,601
Held to maturity, Under 1 Year	13
Held to maturity, 1 to 5 Years	3
Held to maturity, 6 to 10 Years	0
Held to maturity, Over 10 Years	0
Collateralized mortgage obligations	'
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	453
Available for sale, 1 to 5 Years	1,458
Available for sale, 6 to 10 Years	1,059
Available for sale, Over 10 Years	2,292
Held to maturity, Under 1 Year	238
Held to maturity, 1 to 5 Years	960
Held to maturity, 6 to 10 Years	496
Held to maturity, Over 10 Years	1,015
Other U.S.debt securities	'
Contractual Maturities Of Debt Investment Securities [Line Items]	'
Available for sale, Under 1 Year	437
Available for sale, 1 to 5 Years	3,761
Available for sale, 6 to 10 Years	715
Available for sale, Over 10 Years	$33

Investment_Securities_Gains_an

Investment Securities (Gains and Losses Related to Investment Securities) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Investments, Debt and Equity Securities [Abstract]	'	'
Gross realized gains from sales of available-for-sale securities	$15	$57
Gross realized losses from sales of available-for-sale securities	0	-52
Gross losses from other-than-temporary impairment	-1	0
Losses reclassified (from) to other comprehensive income	-8	-3
Gains (losses) related to investment securities, net	6	2
Impairment associated with expected credit losses	-9	0
Impairment associated with adverse changes in timing of expected future cash flows	0	-3
Net impairment losses	($9)	($3)

Investment_Securities_Schedule3

Investment Securities (Schedule of Credit-Related Loss Activity Recognized In Earnings) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]	'	'
Beginning balance	$122	$124
Plus losses for which other-than-temporary impairment was previously recognized	9	3
Less previously recognized losses related to securities sold or matured	-1	0
Less losses related to securities intended or required to be sold	-6	0
Ending balance	$124	$127

Loans_and_Leases_Narrative_Det

Loans and Leases (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Mar. 31, 2014
	loan
Financing Receivable, Recorded Investment [Line Items]	'	'
Loans and leases, allowance for losses	$28,000,000	$30,000,000
Aggregate short-duration advances	2,450,000,000	4,830,000,000
Loans modified in troubled debt restructurings	0	'
Institutional	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Amount of loan losses related to institutional loans collectively evaluated for impairment	28,000,000	30,000,000
Institutional | Senior Secured Bank Loans	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial and financial	724,000,000	1,150,000,000
Commercial and Financial | Senior Secured Bank Loans	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Loans and leases, allowance for losses	'	8,000,000
Commercial Real Estate	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Amount of loan losses related to institutional loans collectively evaluated for impairment	'	28,000,000
Loan modification, recorded investment	130,000,000	130,000,000
Impairment loss recognized	$0	'

Loans_and_Leases_Net_Loans_Det

Loans and Leases (Net Loans) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'
Total loans and leases	$16,114	$13,486
Allowance for loan losses	-30	-28
Loans and leases, net of allowance for loan losses	16,084	13,458
Institutional	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'
Total loans and leases	15,880	13,277
Commercial Real Estate	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'
Total loans and leases	234	209
U.S. | Institutional	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'
Investment funds	10,000	8,695
Commercial and financial	1,895	1,372
Purchased receivables	202	217
Lease financing	337	339
U.S. | Commercial Real Estate	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'
Commercial real estate	234	209
Non-U.S. | Institutional	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'
Investment funds	2,310	1,718
Commercial and financial	363	154
Purchased receivables	20	26
Lease financing	$753	$756

Loans_and_Leases_Recorded_Inve

Loans and Leases (Recorded Investment in Each Class of Total Loans and Leases by Credit Quality Indicator) (Details) (USD $)	Mar. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	$16,114		$13,486
Investment Funds	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	12,310		10,413
Commercial and Financial	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	2,258		1,526
Purchased Receivables	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	222		243
Lease Financing	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	1,090		1,095
Property Development	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	205		180
Other	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	29		29
Investment grade	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	14,322	[1]	12,362	[1]
Investment grade | Investment Funds	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	12,073	[1]	10,282	[1]
Investment grade | Commercial and Financial	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	961	[1]	740	[1]
Investment grade | Purchased Receivables	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	222	[1]	243	[1]
Investment grade | Lease Financing	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	1,037	[1]	1,068	[1]
Investment grade | Property Development	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	0	[1]	0	[1]
Investment grade | Other	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	29	[1]	29	[1]
Speculative	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	1,776	[2]	1,108	[2]
Speculative | Investment Funds	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	237	[2]	131	[2]
Speculative | Commercial and Financial	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	1,281	[2]	770	[2]
Speculative | Purchased Receivables	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	0	[2]	0	[2]
Speculative | Lease Financing	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	53	[2]	27	[2]
Speculative | Property Development	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	205	[2]	180	[2]
Speculative | Other	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	0	[2]	0	[2]
Special mention	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	16	[3]	16	[3]
Special mention | Investment Funds	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	0	[3]	0	[3]
Special mention | Commercial and Financial	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	16	[3]	16	[3]
Special mention | Purchased Receivables	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	0	[3]	0	[3]
Special mention | Lease Financing	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	0	[3]	0	[3]
Special mention | Property Development	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	0	[3]	0	[3]
Special mention | Other	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Total Loans and Leases	$0	[3]	$0	[3]
[1]	Investment-grade loans and leases consist of counterparties with strong credit quality and low expected credit risk and probability of default. Ratings apply to counterparties with a strong capacity to support the timely repayment of any financial commitment.
[2]	Speculative loans and leases consist of counterparties that face ongoing uncertainties or exposure to business, financial, or economic downturns. However, these counterparties may have financial flexibility or access to financial alternatives, which allow for financial commitments to be met.
[3]	Special mention loans and leases consist of counterparties with potential weaknesses that, if uncorrected, may result in deterioration of repayment prospects.

Loans_and_Leases_Schedule_of_A

Loans and Leases (Schedule of Allowance for Loan Losses) (Details) (USD $)	Mar. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Loans and leases, Individually evaluated for impairment	$130		$206
Loans and leases, Collectively evaluated for impairment	15,984	[1]	13,280	[1]
Total loans and leases	16,114		13,486
Institutional	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Loans and leases, Individually evaluated for impairment	0		26
Loans and leases, Collectively evaluated for impairment	15,880	[1]	13,251	[1]
Total loans and leases	15,880		13,277
Commercial Real Estate	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Loans and leases, Individually evaluated for impairment	130		180
Loans and leases, Collectively evaluated for impairment	104	[1]	29	[1]
Total loans and leases	$234		$209
[1]	As of MarchB 31, 2014 and DecemberB 31, 2013, all of the allowance for loan losses of $30 million and $28 million, respectively, related to institutional loans collectively evaluated for impairment.

Loans_and_Leases_Impaired_Loan

Loans and Leases (Impaired Loans) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013	Dec. 31, 2013
CRE - property development	'		'	'
Financing Receivable, Impaired [Line Items]	'		'	'
Recorded investment with no related allowance	$130		'	$130
Unpaid principal balance with no related allowance recorded	143		'	143
Related allowance	0	[1]	'	0	[1]
Average recorded investment	130		195	'
Interest revenue with related allowance recognized	2		4	'
CRE - property development - acquired credit impaired	'		'	'
Financing Receivable, Impaired [Line Items]	'		'	'
Recorded investment with no related allowance	0		'	0
Unpaid principal balance with no related allowance recorded	34		'	34
Related allowance	0	[1]	'	0	[1]
CRE - other - acquired credit impaired	'		'	'
Financing Receivable, Impaired [Line Items]	'		'	'
Recorded investment with no related allowance	0		'	0
Unpaid principal balance with no related allowance recorded	21		'	21
Related allowance	0	[1]	'	0	[1]
Commercial Real Estate	'		'	'
Financing Receivable, Impaired [Line Items]	'		'	'
Recorded investment with no related allowance	130		'	130
Unpaid principal balance with no related allowance recorded	198		'	198
Related allowance	0	[1]	'	0	[1]
Average recorded investment	130		195	'
Interest revenue recognized	$2		$4	'
[1]	As of MarchB 31, 2014 and DecemberB 31, 2013, all of the allowance for loan losses of $30 million and $28 million, respectively, related to loans that were not impaired.

Loans_and_Leases_Schedule_of_A1

Loans and Leases (Schedule of Activity In The Allowance For Loan Losses) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Allowance for Loan and Lease Losses [Roll Forward]	'	'
Beginning balance	$28	$22
Provisions	2	0
Ending balance	30	22
Institutional	'	'
Allowance for Loan and Lease Losses [Roll Forward]	'	'
Beginning balance	28	22
Provisions	2	0
Ending balance	30	22
Commercial Real Estate	'	'
Allowance for Loan and Lease Losses [Roll Forward]	'	'
Beginning balance	0	0
Provisions	0	0
Ending balance	$0	$0

Goodwill_and_Other_Intangible_2

Goodwill and Other Intangible Assets (Changes In The Carrying Amount Of Goodwill) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Goodwill [Roll Forward]	'	'
Beginning balance	$6,036	$5,977
Foreign currency translation, net	2	-65
Ending balance	6,038	5,912
Investment Servicing	'	'
Goodwill [Roll Forward]	'	'
Beginning balance	5,999	5,941
Foreign currency translation, net	2	-64
Ending balance	6,001	5,877
Investment Management	'	'
Goodwill [Roll Forward]	'	'
Beginning balance	37	36
Foreign currency translation, net	0	-1
Ending balance	$37	$35

Goodwill_and_Other_Intangible_3

Goodwill and Other Intangible Assets (Changes In The Carrying Amount Of Other Intangible Assets) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Finite-lived Intangible Assets [Roll Forward]	'	'
Beginning balance	$2,360	$2,539
Amortization	-54	-53
Foreign currency translation, net	0	-34
Ending balance	2,306	2,452
Investment Servicing	'	'
Finite-lived Intangible Assets [Roll Forward]	'	'
Beginning balance	2,321	2,492
Amortization	-52	-51
Foreign currency translation, net	0	-32
Ending balance	2,269	2,409
Investment Management	'	'
Finite-lived Intangible Assets [Roll Forward]	'	'
Beginning balance	39	47
Amortization	-2	-2
Foreign currency translation, net	0	-2
Ending balance	$37	$43

Goodwill_and_Other_Intangible_4

Goodwill and Other Intangible Assets (Gross Carrying Amount, Accumulated Amortization And Net Carrying Amount Of Other Intangible Assets) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Finite-Lived Intangible Assets [Line Items]	'	'	'	'
Gross Carrying Amount	$3,649	$3,657	'	'
Accumulated Amortization	-1,343	-1,297	'	'
Net Carrying Amount	2,306	2,360	2,452	2,539
Client relationships	'	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'	'
Gross Carrying Amount	2,702	2,706	'	'
Accumulated Amortization	-1,011	-975	'	'
Net Carrying Amount	1,691	1,731	'	'
Core deposits	'	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'	'
Gross Carrying Amount	717	717	'	'
Accumulated Amortization	-200	-191	'	'
Net Carrying Amount	517	526	'	'
Other	'	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'	'
Gross Carrying Amount	230	234	'	'
Accumulated Amortization	-132	-131	'	'
Net Carrying Amount	$98	$103	'	'

Other_Assets_Components_of_Oth

Other Assets (Components of Other Assets) (Details) (USD $)	Mar. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Other Assets [Line Items]	'		'
Total	$23,989		$25,990
Real estate acquired through foreclosure	60		59
Reported Amount | Other assets	'		'
Other Assets [Line Items]	'		'
Collateral deposits, net	13,518		13,706
Unrealized gains on derivative financial instruments, net	3,469		5,476
Bank-owned life insurance	2,359		2,343
Investments in joint ventures and other unconsolidated entities	1,712		1,644
Accounts receivable	687		950
Prepaid expenses	359		286
Income taxes receivable	339		337
Receivable for securities settlement	334		195
Deferred tax assets, net of valuation allowance	249		263
Receivable for securities sold	191		0
Deposits with clearing organizations	183		177
Other	589	[1]	613	[1]
Total	$23,989		$25,990
[1]	Included other real estate owned of approximately $60 million and $59 million as of MarchB 31, 2014 and DecemberB 31, 2013, respectively.

Contingencies_Narrative_Detail

Contingencies (Narrative) (Details)

Mar. 31, 2014

Dec. 31, 2013

Aug. 31, 2009

Jan. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Jan. 31, 2014

Jan. 31, 2014

Jan. 31, 2014

Mar. 31, 2014

Aug. 31, 2009

Mar. 31, 2014

Jun. 30, 2013

Mar. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2010

Dec. 31, 2009

Dec. 31, 2008

Dec. 31, 2009

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

In Millions, unless otherwise specified

USD ($)

USD ($)

customer

Transition Management

Transition Management

Transition Management

Transition Management

Transition Management

State Street Global Advisors

State Street Global Advisors

Securities Finance

Securities Finance

Securities Finance

Foreign Exchange

Foreign Exchange

Foreign Exchange

Foreign Exchange

Foreign Exchange

Foreign Exchange

Foreign Exchange

Foreign Exchange

Putative Class Action

Shareholder Litigation

Investment Servicing

claim

USD ($)

Legal Reserve

Regulatory Matter

Regulatory Matter

USD ($)

claim

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

claim

USD ($)

USD ($)

USD ($)

USD ($)

GBP (£)

complaint

shareholder

Loss Contingencies [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Legal reserves

'

'

'

'

'

$111

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of pending claims

'

'

'

'

'

'

'

'

'

2

'

'

'

'

'

'

'

'

'

'

'

2

'

'

Settlement, amount

'

'

'

'

'

'

37.8

22.9

10

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Litigation reserve

'

'

'

'

3

'

'

'

'

'

'

10

'

'

'

'

'

'

'

'

'

'

'

4.6

Number of suits from related participants of agency securities lending program

'

'

2

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Loss contingency, damages sought, value

'

'

'

'

'

'

'

'

'

'

120

'

'

'

'

'

'

'

'

'

'

'

'

'

Realized loss on sales of securities

'

'

'

'

'

'

'

'

'

'

'

'

11

'

'

'

'

'

'

'

'

'

'

'

Actual damages asserted by attorney general

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

100

'

'

'

Estimated indirect foreign exchange revenue

'

'

'

'

'

'

'

'

'

'

'

'

'

63

285

248

331

336

369

462

'

'

'

'

Shareholder related class action complaints pending in Boston Federal Court

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

3

'

Number of class action complaints pending in Boston Federal Court brought on behalf of State Street shareholders

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1

'

Number of class action complaints pending in Boston Federal Court brought on behalf of State Street participants and beneficiaries of State Street Salary Savings Program

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2

'

Litigation reserve net of insurance recovery

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

13

'

Claims settled

'

'

'

6

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unrecognized tax benefits

$163

$164

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Commitments_and_Guarantees_Con

Commitments and Guarantees Contingencies (Details) (USD $)	3 Months Ended
In Billions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Loss Contingencies [Line Items]	'	'
Cash collateral provided for securities lending	$11.32	$11.29
Percent of fair market value that must be maintained in collateral	100.00%	'
Unfunded commitments to extend credit	21.77	21.3
Unfunded commitments to extend credit, short term	77.00%	'
Accrued expenses and other liabilities	'	'
Loss Contingencies [Line Items]	'	'
Cash collateral received in connection to securities finance activities	$6.29	$6.62

Commitments_and_Guarantees_Con1

Commitments and Guarantees (Contractual Amounts of Credit-Related Off-Balance Sheet Financial Instruments) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]	'	'
Indemnified securities financing	$346,789	$320,078
Stable value protection	24,484	24,906
Asset purchase agreements	4,304	4,685
Standby letters of credit	$4,870	$4,612

Commitments_and_Guarantees_Sch

Commitments and Guarantees (Schedule Of Repurchase Agreements) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]	'	'
Aggregate fair value of indemnified securities financing	$346,789	$320,078
Aggregate fair value of cash and securities held by us, as agent, as collateral for indemnified securities financing	358,240	331,732
Aggregate fair value of collateral for indemnified securities financing invested in indemnified repurchase agreements	94,423	85,374
Aggregate fair value of cash and securities held by us or our agents as collateral for investments in indemnified repurchase agreements	$99,935	$91,097

Variable_Interest_Entities_Det

Variable Interest Entities (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Variable Interest Entities [Abstract]	'	'	'
Investment securities related to state and political subdivisions	$2,330,000,000	'	$2,330,000,000
Variable interest entity, other short-term borrowings	1,930,000,000	'	1,950,000,000
Weighted average life of trusts (in years)	'6 years 3 months 15 days	'6 years 6 months	'
Total standby bond-purchase agreement committed to trusts	1,960,000,000	'	'
Letters of credit amounts outstanding	684,000,000	'	'
Standby purchase agreements and letters of credit commitments utilized	0	'	'
Variable Interest Entity [Line Items]	'	'	'
Potential maximum loss exposure of unconsolidated funds	24,000,000	'	18,000,000
Variable Interest Entity, Primary Beneficiary	'	'	'
Variable Interest Entity [Line Items]	'	'	'
Assets	60,000,000	'	50,000,000
Liabilities	$10,000,000	'	'

Shareholders_Equity_Narrative_

Shareholders' Equity (Narrative) (Details) (USD $)

3 Months Ended

12 Months Ended

3 Months Ended

1 Months Ended

3 Months Ended

1 Months Ended

3 Months Ended

Mar. 31, 2014

Mar. 31, 2013

Dec. 31, 2012

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Feb. 28, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

March 2014 Repurchase Program

March 2013 Repurchase Program

March 2013 Repurchase Program

Depositary Shares

Depositary Shares

Series C Preferred Stock

Retained Earnings

Retained Earnings

Series D Preferred Stock

Equity, Class of Treasury Stock [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

Stock issued during period

'

'

'

'

'

'

30,000,000

'

'

'

'

'

Depositary shares, ownership interest

'

'

'

'

'

'

'

'

0.03%

'

'

0.03%

Liquidation preference (in dollars per share)

'

'

'

'

'

'

'

$25

$100,000

'

'

'

Proceeds from issuance of preferred stock

$742,000,000

$0

'

'

'

'

$742,000,000

'

'

'

'

'

Preferred stock dividends (in dollars per share)

'

'

'

'

'

'

'

$0.33

$1,312.50

'

'

'

Preferred stock cash dividend

-6,000,000

-7,000,000

'

'

'

'

'

'

'

-6,000,000

-7,000,000

'

Dividend rate

'

'

'

'

'

'

'

'

5.25%

'

'

5.90%

Redemption price (in dollars per share)

'

'

'

'

'

'

'

$25

$100,000

'

'

'

Amount of common stock authorized for repurchase

'

'

'

'

1,700,000,000

'

'

'

'

'

'

'

Cash dividends declared (in dollars per share)

$0.26

$0.26

'

'

'

'

'

'

'

'

'

'

Common stock dividends

-112,000,000

-118,000,000

'

'

'

'

'

'

'

-112,000,000

-118,000,000

'

Net gains (losses) from sales of available-for-sale securities

-15,000,000

'

'

'

'

'

'

'

'

'

'

'

Net after tax realized gains (losses) on AFS securities

-9,000,000

'

'

'

'

'

'

'

'

'

'

'

Unrealized pretax gains (losses) on securities included in AOCI

'

5,000,000

-49,000,000

'

'

'

'

'

'

'

'

'

Deferred taxes on unrealized pretax gains (losses) on securities included in AOCI

'

3,000,000

20,000,000

'

'

'

'

'

'

'

'

'

Realized gains (losses) from sale of available-for-sale securities

'

3,000,000

'

'

'

'

'

'

'

'

'

'

Common stock acquired (shares)

'

'

'

0

'

6,100,000

'

'

'

'

'

'

Treasury Stock Acquired, Average Cost Per Share

'

'

'

'

'

$69.14

'

'

'

'

'

'

Stock Repurchased During Period, Value

'

'

'

'

'

$420,000,000

'

'

'

'

'

'

Shares available for purchase

'

'

'

'

'

0

'

'

'

'

'

'

Shareholders_Equity_Schedule_O

Shareholders' Equity (Schedule Of Accumulated Other Comprehensive (Loss) Income) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Stockholders' Equity Note [Abstract]	'	'
Net unrealized gains on cash flow hedges	$154	$161
Net unrealized gains (losses) on available-for-sale securities portfolio	194	-56
Net unrealized losses related to reclassified available-for-sale securities	-61	-72
Net unrealized gains (losses) on available-for-sale securities	133	-128
Net unrealized losses on available-for-sale securities designated in fair value hedges	-107	-97
Other-than-temporary impairment on available-for-sale securities related to factors other than credit	2	4
Net unrealized losses on hedges of net investments in non-U.S. subsidiaries	-14	-14
Other-than-temporary impairment on held-to-maturity securities related to factors other than credit	-39	-47
Net unrealized losses on retirement plans	-197	-203
Foreign currency translation	256	229
Total	$188	($95)

Shareholders_Equity_Accumulate

Shareholders' Equity (Accumulated Other Comprehensive Income by Component) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]	'	'
AOCI net of tax, beginning balance	($95)	'
Other comprehensive income (loss)	283	-109
AOCI net of tax, ending balance	188	'
Accumulated Other Comprehensive Income (Loss)	'	'
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]	'	'
AOCI net of tax, beginning balance	-95	360
Other comprehensive income (loss) before reclassifications	286	-114
Amounts reclassified out of AOCI	-3	5
Other comprehensive income (loss)	283	-109
AOCI net of tax, ending balance	188	251
Net Unrealized Gains (Losses) on Cash Flow Hedges	'	'
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]	'	'
AOCI net of tax, beginning balance	161	69
Other comprehensive income (loss) before reclassifications	-8	63
Amounts reclassified out of AOCI	1	1
Other comprehensive income (loss)	-7	64
AOCI net of tax, ending balance	154	133
Net Unrealized Gains (Losses) on Available-for-Sale Securities	'	'
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]	'	'
AOCI net of tax, beginning balance	-221	519
Other comprehensive income (loss) before reclassifications	258	69
Amounts reclassified out of AOCI	-9	-3
Other comprehensive income (loss)	249	66
AOCI net of tax, ending balance	28	585
Net Unrealized Losses on Hedges of Net Investments in Non-U.S. Subsidiaries	'	'
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]	'	'
AOCI net of tax, beginning balance	-14	-14
Other comprehensive income (loss) before reclassifications	0	0
Amounts reclassified out of AOCI	0	0
Other comprehensive income (loss)	0	0
AOCI net of tax, ending balance	-14	-14
Other-Than-Temporary Impairment on Held-to-Maturity Securities	'	'
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]	'	'
AOCI net of tax, beginning balance	-47	-65
Other comprehensive income (loss) before reclassifications	8	4
Amounts reclassified out of AOCI	0	2
Other comprehensive income (loss)	8	6
AOCI net of tax, ending balance	-39	-59
Net Unrealized Losses on Retirement Plans	'	'
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]	'	'
AOCI net of tax, beginning balance	-203	-283
Other comprehensive income (loss) before reclassifications	1	-2
Amounts reclassified out of AOCI	5	5
Other comprehensive income (loss)	6	3
AOCI net of tax, ending balance	-197	-280
Foreign Currency Translation	'	'
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]	'	'
AOCI net of tax, beginning balance	229	134
Other comprehensive income (loss) before reclassifications	27	-248
Amounts reclassified out of AOCI	0	0
Other comprehensive income (loss)	27	-248
AOCI net of tax, ending balance	$256	($114)

Shareholders_Equity_Adjustment

Shareholders' Equity (Adjustments to Accumulated Other Comprehensive Income) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Class of Stock [Line Items]	'	'
Net interest revenue	$555	$576
Net gains (losses) from sales of available-for-sale securities	-15	'
Total reclassifications out of AOCI	356	455
Reclassification out of Accumulated Other Comprehensive Income [Member]	'	'
Class of Stock [Line Items]	'	'
Total reclassifications out of AOCI	-3	5
Net Unrealized Gains (Losses) on Cash Flow Hedges | Interest-rate contracts | Reclassification out of Accumulated Other Comprehensive Income [Member]	'	'
Class of Stock [Line Items]	'	'
Net interest revenue	1	1
Net Unrealized Gains (Losses) on Available-for-Sale Securities | Reclassification out of Accumulated Other Comprehensive Income [Member]	'	'
Class of Stock [Line Items]	'	'
Net gains (losses) from sales of available-for-sale securities	-9	-3
Net realized gain from sales of available-for-sale securities, tax	-6	-2
Other-Than-Temporary Impairment on Held-to-Maturity Securities | Reclassification out of Accumulated Other Comprehensive Income [Member]	'	'
Class of Stock [Line Items]	'	'
Held-to-maturity securities, Losses reclassified (from) to other comprehensive income	0	2
Other-than-temporary impairment on held-to-maturity securities related to factors other than credit, tax	1	0
Net Unrealized Losses on Retirement Plans | Reclassification out of Accumulated Other Comprehensive Income [Member]	'	'
Class of Stock [Line Items]	'	'
Amortization of actuarial losses, net of related tax benefits of $3 and $3, respectively	5	5
Amortization of actuarial losses, tax	$3	$3

Derivative_Financial_Instrumen2

Derivative Financial Instruments (Narrative) (Details) (USD $)

3 Months Ended

3 Months Ended

12 Months Ended

Mar. 31, 2014

Mar. 31, 2013

Dec. 31, 2013

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Fair Value Hedges

Fair Value Hedges

Cash Flow Hedges

Cash Flow Hedges

Credit swap agreements

Interest rate swap

Interest rate swap

Interest rate swap

1.35% Senior Note

3.70% senior notes due in 2023

Fair Value Hedges

Fair Value Hedges

Fair Value Hedges

3.1% Subordinated Note

Senior notes

Subordinated note

security

security

Derivative [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Cash collateral received for derivative instruments

$1,740,000,000

'

$2,580,000,000

'

'

'

'

'

'

'

'

Cash collateral provided for derivative instruments

2,460,000,000

'

3,360,000,000

'

'

'

'

'

'

'

'

Fair value of derivative liabilities

8,121,000,000

[1]

'

11,811,000,000

[1]

'

'

'

'

422,000,000

'

'

'

Maximum additional amount of payments related to termination events

'

'

'

'

'

'

'

$422,000,000

'

'

'

Weighted average life of trusts (in years)

'6 years 3 months 15 days

'6 years 6 months

'

'

'

'

'

'

'

'

'

Number of securities

'

'

'

'

'

'

'

'

'

2

1

Fixed interest rate

'

'

'

1.35%

3.70%

'

'

'

3.10%

'

'

Securities weighted average life (in years)

'

'

'

'

'

'7 months

'10 months

'

'

'

'

[1]

Amounts include all transactions regardless of whether or not they are subject to an enforceable netting arrangement.

Derivative_Financial_Instrumen3

Derivative Financial Instruments (Schedule of Outstanding Hedges: (Notional Amount)) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	$5,222	$5,221
Credit derivative contracts | Derivatives not designated as hedging instruments	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	180	0
Swap agreements and forwards | Interest-rate contracts | Derivatives not designated as hedging instruments	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	878	1,023
Futures | Interest-rate contracts | Derivatives not designated as hedging instruments	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	3,731	3,282
Futures | Foreign exchange contracts | Derivatives not designated as hedging instruments	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	14	0
Forward, swap and spot | Foreign exchange contracts | Derivatives not designated as hedging instruments	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	1,232,146	1,124,355
Options purchased | Foreign exchange contracts | Derivatives not designated as hedging instruments	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	1,484	1,666
Options written | Foreign exchange contracts | Derivatives not designated as hedging instruments	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	1,140	1,423
Credit swap agreements | Credit derivative contracts | Derivatives not designated as hedging instruments	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	141	141
Commodity(1) | Futures Contracts | Derivatives not designated as hedging instruments	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	11,363	2
Equity(1) | Futures Contracts | Derivatives not designated as hedging instruments	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	18	1
Stable value contracts | Other contracts | Derivatives not designated as hedging instruments	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	24,484	24,906
Swap agreements | Interest-rate contracts | Derivatives designated as hedging instruments	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	5,222	5,221
Forward and swap | Foreign exchange contracts | Derivatives designated as hedging instruments	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	2,866	2,783
Long | Options and caps purchased | Interest-rate contracts | Derivatives not designated as hedging instruments	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	20	27
Short | Options and caps purchased | Interest-rate contracts | Derivatives not designated as hedging instruments	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Notional amount of derivatives	$20	$27

Derivative_Financial_Instrumen4

Derivative Financial Instruments (Notional Amount of Interest Rate Swap Agreements Designated as Fair Value and Cash Flow Hedges) (Details) (USD $)	3 Months Ended		12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Derivative [Line Items]	'		'
Total	$5,222		$5,221
Increase in carrying value of long-term debt	3		35
Investment securities available for sale	'		'
Derivative [Line Items]	'		'
Investment securities available for sale	2,722		2,721
Long-term debt	'		'
Derivative [Line Items]	'		'
Long-term debt	2,500	[1]	2,500	[1]
Fair Value Hedges	'		'
Derivative [Line Items]	'		'
Total	5,089		5,089
Fair Value Hedges | Investment securities available for sale	'		'
Derivative [Line Items]	'		'
Investment securities available for sale	2,589		2,589
Fair Value Hedges | Long-term debt	'		'
Derivative [Line Items]	'		'
Long-term debt	2,500	[1]	2,500	[1]
Cash Flow Hedges	'		'
Derivative [Line Items]	'		'
Total	133		132
Cash Flow Hedges | Investment securities available for sale	'		'
Derivative [Line Items]	'		'
Investment securities available for sale	133		132
Cash Flow Hedges | Long-term debt	'		'
Derivative [Line Items]	'		'
Long-term debt	$0	[1]	$0	[1]
[1]	As of MarchB 31, 2014, these fair value hedges increased the carrying value of long-term debt presented in our consolidated statement of condition by $3 million. As of DecemberB 31, 2013, these fair value hedges decreased the carrying value of long-term debt presented in our consolidated statement of condition by $35 million.

Derivative_Financial_Instrumen5

Derivative Financial Instruments (Contractual and Weighted-Average Interest Rates, Which Include the Effects of Hedges Related to Financial Instruments) (Details) (Long-term debt)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Long-term debt	'	'
Derivative [Line Items]	'	'
Contractual Rates	3.39%	3.77%
Rate Including Impact of Hedges	2.60%	3.03%

Derivative_Financial_Instrumen6

Derivative Financial Instruments (Schedule of The Fair Values of Derivative Financial Instruments) (Details) (USD $)	Mar. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative assets	$8,376		$11,977	[1]
Fair value of derivative liabilities	8,121	[1]	11,811	[1]
Foreign exchange contracts	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative assets	8,318		11,911	[1]
Fair value of derivative liabilities	7,842	[1]	11,471	[1]
Interest-rate contracts	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative assets	56		65	[1]
Fair value of derivative liabilities	269	[1]	331	[1]
Derivatives not designated as hedging instruments | Other assets	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative assets	8,035		11,582
Derivatives not designated as hedging instruments | Other liabilities	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative liabilities	7,802		11,466
Derivatives not designated as hedging instruments | Foreign exchange contracts | Other assets	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative assets	8,012		11,552
Derivatives not designated as hedging instruments | Foreign exchange contracts | Other liabilities	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative liabilities	7,771		11,428
Derivatives not designated as hedging instruments | Interest-rate contracts | Other assets	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative assets	21		29
Derivatives not designated as hedging instruments | Interest-rate contracts | Other liabilities	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative liabilities	21		29
Derivatives not designated as hedging instruments | Other derivative contracts | Other assets	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative assets	2		1
Derivatives not designated as hedging instruments | Other derivative contracts | Other liabilities	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative liabilities	10		9
Derivatives designated as hedging instruments | Other assets	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative assets	341		395
Derivatives designated as hedging instruments | Other liabilities	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative liabilities	319		345
Derivatives designated as hedging instruments | Foreign exchange contracts | Other assets	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative assets	306		359
Derivatives designated as hedging instruments | Foreign exchange contracts | Other liabilities	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative liabilities	71		43
Derivatives designated as hedging instruments | Interest-rate contracts | Other assets	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative assets	35		36
Derivatives designated as hedging instruments | Interest-rate contracts | Other liabilities	'		'
Derivatives, Fair Value [Line Items]	'		'
Fair value of derivative liabilities	$248		$302
[1]	Amounts include all transactions regardless of whether or not they are subject to an enforceable netting arrangement.

Derivative_Financial_Instrumen7

Derivative Financial Instruments (Impact of Derivatives on Consolidated Statement of Income) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Derivatives not designated as hedging instruments	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	$133	$146
Derivatives designated as fair value hedges	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	79	-10
Amount of Gain (Loss) on Hedged Item Recognized in Consolidated Statement of Income	-75	10
Foreign exchange contracts | Trading services | Derivatives not designated as hedging instruments	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	134	145
Foreign exchange contracts | Processing fees and other revenue | Derivatives designated as fair value hedges	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	42	4
Foreign exchange contracts | Processing fees and other revenue | Investment securities | Derivatives designated as fair value hedges	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) on Hedged Item Recognized in Consolidated Statement of Income	-42	-4
Interest-rate contracts | Trading services | Derivatives not designated as hedging instruments	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	0	1
Interest-rate contracts | Processing fees and other revenue | Contract one | Derivatives designated as fair value hedges	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	-12	1
Interest-rate contracts | Processing fees and other revenue | Contract two | Derivatives designated as fair value hedges	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	49	-15
Interest-rate contracts | Processing fees and other revenue | Long-term debt | Derivatives designated as fair value hedges	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) on Hedged Item Recognized in Consolidated Statement of Income	12	-2
Interest-rate contracts | Processing fees and other revenue | Investment securities available for sale | Derivatives designated as fair value hedges	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) on Hedged Item Recognized in Consolidated Statement of Income	-45	16
Other derivative contracts | Processing fees and other revenue | Derivatives not designated as hedging instruments	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	($1)	$0

Derivative_Financial_Instrumen8

Derivative Financial Instruments (Schedule of Differences Between the Gains (Losses) on the Derivative and The Gains (Losses) on the Hedged Item) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Derivative [Line Items]	'	'
Amount of Gain (Loss) Reclassified from OCI to Consolidated Statement of Income	$2,485	$2,435
Derivatives designed as cash flow value hedges	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) on Derivative Recognized in Other Comprehensive Income	-13	117
Amount of Gain (Loss) Reclassified from OCI to Consolidated Statement of Income	-1	-1
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	2	4
Interest-rate contracts | Derivatives designed as cash flow value hedges	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) on Derivative Recognized in Other Comprehensive Income	-1	12
Interest-rate contracts | Net interest revenue | Derivatives designed as cash flow value hedges	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) Reclassified from OCI to Consolidated Statement of Income	-1	-1
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	1	1
Foreign exchange contracts | Derivatives designed as cash flow value hedges	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) on Derivative Recognized in Other Comprehensive Income	-12	105
Foreign exchange contracts | Net interest revenue | Derivatives designed as cash flow value hedges	'	'
Derivative [Line Items]	'	'
Amount of Gain (Loss) Reclassified from OCI to Consolidated Statement of Income	0	0
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	$1	$3

Offsetting_Arrangements_Narrat

Offsetting Arrangements (Narrative) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Billions, unless otherwise specified
Offsetting [Abstract]	'	'
Fair Value of Securities Received as Collateral that Can be Resold or Repledged	$4.60	$5.64
Fair Value of Securities Received as Collateral that Have Been Resold or Repledged	$1.53	$1.77

Offsetting_Arrangements_Assets

Offsetting Arrangements (Assets With Offsetting Arrangements) (Details) (USD $)	Mar. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Offsetting Assets [Line Items]	'		'
Derivatives, Gross Amounts of Recognized Assets	$8,376		$11,977	[1]
Derivatives, Gross Amounts Offset in Statement of Condition	-4,907	[2]	-6,501	[2]
Net Amounts of Assets Presented in Statement of Condition	3,469		5,476
Resale Agreements and Securities Borrowing, Gross Amounts of Recognized Assets	47,715	[3]	48,221	[1],[3]
Resale Agreements and Securities Borrowing, Gross Amounts Offset in Statement of Condition	-30,307	[2],[3]	-30,700	[2],[3]
Net Amounts of Assets Presented in Statement of Condition	17,408	[3]	17,521	[3]
Total, Gross Amounts of Recognized Assets	56,091		60,198	[1]
Total, Gross Amounts Offset in Statement of Condition	-35,214	[2]	-37,201	[2]
Total, Net Amounts of Assets Presented in Statement of Condition	20,877		22,997
Securities purchased under resale agreements	6,087		6,230
Securities borrowed subject to master netting arrangements	11,321		11,291
Cash collateral netting	'		'
Offsetting Assets [Line Items]	'		'
Derivatives, Gross Amounts of Recognized Assets	0		0	[1]
Derivatives, Gross Amounts Offset in Statement of Condition	-1,372	[2]	-1,928	[2]
Net Amounts of Assets Presented in Statement of Condition	-1,372		-1,928
Interest-rate contracts	'		'
Offsetting Assets [Line Items]	'		'
Derivatives, Gross Amounts of Recognized Assets	56		65	[1]
Derivatives, Gross Amounts Offset in Statement of Condition	-45	[2]	-59	[2]
Net Amounts of Assets Presented in Statement of Condition	11		6
Foreign exchange contracts	'		'
Offsetting Assets [Line Items]	'		'
Derivatives, Gross Amounts of Recognized Assets	8,318		11,911	[1]
Derivatives, Gross Amounts Offset in Statement of Condition	-3,489	[2]	-4,514	[2]
Net Amounts of Assets Presented in Statement of Condition	4,829		7,397
Other derivative contracts	'		'
Offsetting Assets [Line Items]	'		'
Derivatives, Gross Amounts of Recognized Assets	2		1
Derivatives, Gross Amounts Offset in Statement of Condition	-1		0
Net Amounts of Assets Presented in Statement of Condition	$1		$1
[1]	Amounts include all transactions regardless of whether or not they are subject to an enforceable netting arrangement.
[2]	Amounts subject to netting arrangements which have been determined to be legally enforceable.
[3]	Included in the $17,408 million as of MarchB 31, 2014 was $6,087 million of resale agreements and $11,321 million of collateral provided related to securities borrowing. Included in the $17,521 million as of DecemberB 31, 2013 was $6,230 million of resale agreements and $11,291 million of collateral provided related to securities borrowing. Resale agreements and collateral provided related to securities borrowing were recorded in securities purchased under resale agreements and other assets, respectively, in our consolidated statement of condition. Refer to note 7 for additional information with respect to principal securities finance transactions.

Offsetting_Arrangements_Assets1

Offsetting Arrangements (Assets With Enforceable Netting Arrangements) (Details) (USD $)	Mar. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Offsetting [Abstract]	'		'
Derivative, Net Amount of Assets Presented in Statement of Condition	$3,469		$5,476
Derivatives, Counterparty Netting	0	[1]	0	[1]
Derivatives, Collateral Received	-187	[1]	-181	[1]
Derivatives, Net Amount	3,282	[2]	5,295	[2]
Resale Agreements and Securities Borrowing, Resale Agreements and Securities Borrowing, Net Amount of Assets Presented in Statement of Condition	17,408	[3]	17,521	[3]
Resale Agreements and Securities Borrowing, Counterparty Netting	-113	[1]	-131	[1]
Resale Agreements and Securities Borrowing, Collateral Received	-15,099	[1]	-14,983	[1]
Resale Agreements and Securities Borrowing, Net Amount	2,196	[2]	2,407	[2]
Total, Net Amounts of Assets Presented in Statement of Condition	20,877		22,997
Total, Counterparty Netting	-113	[1]	-131	[1]
Total, Collateral Received	-15,286	[1]	-15,164	[1]
Total, Net Amount	$5,478	[2]	$7,702	[2]
[1]	Amounts subject to netting arrangements which have been determined to be legally enforceable
[2]	Includes amounts secured by collateral not determined to be subject to enforceable netting arrangements.
[3]	Included in the $17,408 million as of MarchB 31, 2014 was $6,087 million of resale agreements and $11,321 million of collateral provided related to securities borrowing. Included in the $17,521 million as of DecemberB 31, 2013 was $6,230 million of resale agreements and $11,291 million of collateral provided related to securities borrowing. Resale agreements and collateral provided related to securities borrowing were recorded in securities purchased under resale agreements and other assets, respectively, in our consolidated statement of condition. Refer to note 7 for additional information with respect to principal securities finance transactions.

Offsetting_Arrangements_Liabil

Offsetting Arrangements (Liabilities With Offsetting Arrangements) (Details) (USD $)	Mar. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Offsetting Liabilities [Line Items]	'		'
Gross Amounts of Recognized Liabilities	$8,121	[1]	$11,811	[1]
Gross Amounts Offset in Statement of Condition	-3,809	[1]	-5,552	[1],[2]
Net Amounts of Liabilities Presented in Statement of Condition	4,312	[1]	6,259
Gross Amounts of Recognized Liabilities	45,545	[1],[3]	45,273	[1],[3]
Gross Amounts Offset in Statement of Condition	-30,307	[2],[3]	-30,700	[2],[3]
Net Amounts of Liabilities Presented in Statement of Condition	15,238	[3]	14,573	[3]
Gross Amounts of Recognized Liabilities	53,666	[1]	57,084	[1]
Gross Amounts Offset in Statement of Condition	-34,116	[2]	-36,252	[2]
Total, Net Amount of Liabilities Presented in Statement of Condition	19,550		20,832
Securities sold under repurchase agreements	8,953		7,953
Securities Lending, Fair Value, Amount Not Offset Against Collateral	6,285		6,620
Cash collateral netting	'		'
Offsetting Liabilities [Line Items]	'		'
Gross Amounts of Recognized Liabilities	0	[1]	0	[1]
Gross Amounts Offset in Statement of Condition	-274		-979	[2]
Net Amounts of Liabilities Presented in Statement of Condition	-274		-979
Interest-rate contracts	'		'
Offsetting Liabilities [Line Items]	'		'
Gross Amounts of Recognized Liabilities	269	[1]	331	[1]
Gross Amounts Offset in Statement of Condition	-45	[2]	-59	[2]
Net Amounts of Liabilities Presented in Statement of Condition	224		272
Foreign exchange contracts	'		'
Offsetting Liabilities [Line Items]	'		'
Gross Amounts of Recognized Liabilities	7,842	[1]	11,471	[1]
Gross Amounts Offset in Statement of Condition	-3,489	[2]	-4,514	[2]
Net Amounts of Liabilities Presented in Statement of Condition	4,353		6,957
Other derivative contracts	'		'
Offsetting Liabilities [Line Items]	'		'
Gross Amounts of Recognized Liabilities	10		9	[1]
Gross Amounts Offset in Statement of Condition	-1		0	[2]
Net Amounts of Liabilities Presented in Statement of Condition	$9		$9
[1]	Amounts include all transactions regardless of whether or not they are subject to an enforceable netting arrangement.
[2]	Amounts subject to netting arrangements which have been determined to be legally enforceable.
[3]	Included in the $15,238 million as of MarchB 31, 2014 was $8,953 million of repurchase agreements and $6,285 million of collateral received related to securities lending. Included in the $14,573 million as of DecemberB 31, 2013 was $7,953 million of repurchase agreements and $6,620 million of collateral received related to securities lending. Repurchase agreements and collateral received related to securities lending were recorded in securities sold under repurchase agreements and accrued expenses and other liabilities, respectively, in our consolidated statement of condition. Refer to note 7 for additional information with respect to principal securities finance transactions.

Offsetting_Arrangements_Liabil1

Offsetting Arrangements (Liabilities With Enforceable Netting Arrangements) (Details) (USD $)	Mar. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Offsetting [Abstract]	'		'
Derivative, Net Amount of Liabilities Presented in Statement of Condition	$4,312	[1]	$6,259
Derivative, Counterparty Netting	0	[2]	0	[2]
Derivative, Collateral Provided	0	[2]	-6	[2]
Derivative, Net Amount	4,312	[3]	6,253	[3]
Repurchase Agreements and Securities Lending, Net Amount of Liabilities Presented in Statement of Condition	15,238	[4]	14,573	[4]
Repurchase Agreements and Securities Lending, Counterparty Netting	-113	[2]	-131	[2]
Repurchase Agreements and Securities Lending, Collateral Provided	-13,015	[2]	-13,036	[2]
Repurchase Agreements and Securities Lending, Net Amount	2,110	[3]	1,406	[3]
Total, Net Amount of Liabilities Presented in Statement of Condition	19,550		20,832
Total, Counterparty Netting	-113	[2]	-131	[2]
Total, Collateral Provided	-13,015	[2]	-13,042	[2]
Total, Net Amount	$6,422	[3]	$7,659	[3]
[1]	Amounts include all transactions regardless of whether or not they are subject to an enforceable netting arrangement.
[2]	Amounts subject to netting arrangements which have been determined to be legally enforceable
[3]	Includes amounts secured by collateral not determined to be subject to enforceable netting arrangements.
[4]	Included in the $15,238 million as of MarchB 31, 2014 was $8,953 million of repurchase agreements and $6,285 million of collateral received related to securities lending. Included in the $14,573 million as of DecemberB 31, 2013 was $7,953 million of repurchase agreements and $6,620 million of collateral received related to securities lending. Repurchase agreements and collateral received related to securities lending were recorded in securities sold under repurchase agreements and accrued expenses and other liabilities, respectively, in our consolidated statement of condition. Refer to note 7 for additional information with respect to principal securities finance transactions.

Net_Interest_Revenue_Component

Net Interest Revenue (Components of Interest Revenue and Interest Expenses) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Net Interest Revenue [Abstract]	'	'
Deposits with banks	$34	$31
U.S. Treasury and federal agencies	163	194
State and political subdivisions	71	51
Other investments	319	341
Securities purchased under resale agreements	9	13
Loans and leases	58	56
Other interest-earning assets	1	1
Total interest revenue	655	687
Deposits	15	34
Short-term borrowings	15	16
Long-term debt	63	56
Other interest-bearing liabilities	7	5
Total interest expense	100	111
Net interest revenue	$555	$576

Expenses_Narrative_Details

Expenses (Narrative) (Details) (USD $)

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

In Millions, unless otherwise specified

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2010

Dec. 31, 2011

Dec. 31, 2010

Mar. 31, 2014

Mar. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2012

Dec. 31, 2012

Business Operations And Information Technology Transformation Program

Business Operations And Information Technology Transformation Program

Business Operations And Information Technology Transformation Program

Business Operations And Information Technology Transformation Program

Business Operations And Information Technology Transformation Program

Business Operations And Information Technology Transformation Program

Business Operations And Information Technology Transformation Program

Business Operations And Information Technology Transformation Program

Expenses Control Measures - Additional Targeted Staff Reductions

Expenses Control Measures - Additional Targeted Staff Reductions

Expenses Control Measures - Additional Targeted Staff Reductions

Expenses Control Measures - Additional Targeted Staff Reductions

Expenses Control Measures - Additional Targeted Staff Reductions

Involuntary Terminations

Involuntary Terminations

Involuntary Terminations

Involuntary Terminations

Involuntary Terminations After Replacements

employee

employee

employee

employee

employee

Business Acquisition [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Severance costs

$72

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Restructuring charges incurred to date

'

'

390

'

'

'

'

'

'

'

'

'

'

'

'

Restructuring charges, net

$12

($1)

$9

$25

$67

$133

$156

'

'

'

$3

$3

$133

'

'

Expected number of positions eliminated

'

'

'

'

'

'

'

1,436

1,400

'

'

'

'

960

630

Percent of actual number of positions eliminated

'

'

'

'

'

'

'

5.00%

'

'

'

'

'

'

'

Number of positions eliminated from inception to date

'

'

'

'

'

'

'

'

'

1,375

'

'

'

'

'

Expenses_Costs_Related_To_Acqu

Expenses (Costs Related To Acquisition And Restructuring) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Other Expenses [Abstract]	'	'
Acquisition costs	$21	$15
Restructuring charges, net	12	-1
Total acquisition and restructuring costs	$33	$14

Expenses_Activity_Related_To_R

Expenses (Activity Related To Restructuring-Related Accruals) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014
Restructuring Reserve [Roll Forward]	'
Balance as of December 31, 2013	$106
Additional accruals for Business Operations and Information Technology Transformation program	9
Payments and adjustments	-31
Balance as of March 31, 2014	87
2012 Expense Control Measures	'
Restructuring Reserve [Roll Forward]	'
Additional accruals for 2012 expense control measures	3
Employee- Related Costs	'
Restructuring Reserve [Roll Forward]	'
Balance as of December 31, 2013	50
Additional accruals for Business Operations and Information Technology Transformation program	6
Payments and adjustments	-17
Balance as of March 31, 2014	39
Employee- Related Costs | 2012 Expense Control Measures	'
Restructuring Reserve [Roll Forward]	'
Additional accruals for 2012 expense control measures	0
Real Estate Consolidation	'
Restructuring Reserve [Roll Forward]	'
Balance as of December 31, 2013	49
Additional accruals for Business Operations and Information Technology Transformation program	3
Payments and adjustments	-12
Balance as of March 31, 2014	40
Real Estate Consolidation | 2012 Expense Control Measures	'
Restructuring Reserve [Roll Forward]	'
Additional accruals for 2012 expense control measures	0
Asset and Other Write-Offs	'
Restructuring Reserve [Roll Forward]	'
Balance as of December 31, 2013	7
Additional accruals for Business Operations and Information Technology Transformation program	0
Payments and adjustments	-2
Balance as of March 31, 2014	8
Asset and Other Write-Offs | 2012 Expense Control Measures	'
Restructuring Reserve [Roll Forward]	'
Additional accruals for 2012 expense control measures	$3

Earnings_Per_Common_Share_Comp

Earnings Per Common Share (Computation of Basic and Diluted Earnings Per Share) (Details) (USD $)	3 Months Ended
In Millions, except Share data in Thousands, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013
Earnings Per Share [Abstract]	'		'
Net income	$363		$464
Less: Preferred stock dividends	-6		-7
Less: Dividends and undistributed earnings allocated to participating securities	-1	[1]	-2	[1]
Net income available to common shareholders	$356		$455
Basic average common shares	430,621		454,315
Effect of dilutive securities: common stock options and common stock awards (in shares)	8,194		8,436
Diluted average shares	438,815		462,751
Anti-dilutive securities (in shares)	1,504	[2]	2,488	[2]
Earnings per Common Share:	'		'
Basic (in dollars per share)	$0.83		$1
Diluted (in dollars per share)	$0.81	[3]	$0.98	[3]
[1]	Represented the portion of net income available to common equity allocated to participating securities, composed of fully vested deferred director stock and unvested restricted stock that contain non-forfeitable rights to dividends during the vesting period on a basis equivalent to dividends paid to common shareholders.
[2]	Represented common stock options and other equity-based awards outstanding but not included in the computation of diluted average shares, because their effect was anti-dilutive.
[3]	Calculations reflect allocation of earnings to participating securities using the two-class method, as this computation is more dilutive than the treasury stock method.

Line_of_Business_Information_D

Line of Business Information (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
	line_of_business
Segment Reporting Information [Line Items]	'	'	'
Number of lines of business	2	'	'
Acquisition and restructuring costs	$33	$14	'
Severance costs	72	'	'
Servicing fees	1,238	1,175	'
Management fees	292	263	'
Trading services	239	281	'
Securities finance	85	78	'
Processing fees and other	70	60	'
Total fee revenue	1,924	1,857	'
Net interest revenue	555	576	'
Gains (losses) related to investment securities, net	6	2	'
Total revenue	2,485	2,435	'
Provision for loan losses	2	0	'
Total expenses	2,028	1,826	'
Income before income tax expense	455	609	'
Pre-tax margin	18.00%	25.00%	'
Average assets	256,663	'	243,291
Investment Servicing	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Servicing fees	1,238	1,175	'
Management fees	0	0	'
Trading services	227	257	'
Securities finance	85	78	'
Processing fees and other	69	55	'
Total fee revenue	1,619	1,565	'
Net interest revenue	538	557	'
Gains (losses) related to investment securities, net	6	2	'
Total revenue	2,163	2,124	'
Provision for loan losses	2	0	'
Total expenses	1,673	1,590	'
Income before income tax expense	488	534	'
Pre-tax margin	23.00%	25.00%	'
Average assets	212,200	204,400	'
Investment Management	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Servicing fees	0	0	'
Management fees	292	263	'
Trading services	12	24	'
Securities finance	0	0	'
Processing fees and other	1	5	'
Total fee revenue	305	292	'
Net interest revenue	17	19	'
Gains (losses) related to investment securities, net	0	0	'
Total revenue	322	311	'
Provision for loan losses	0	0	'
Total expenses	244	222	'
Income before income tax expense	78	89	'
Pre-tax margin	24.00%	29.00%	'
Average assets	3,400	3,900	'
Other	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Acquisition and restructuring costs	33	'	'
Provision for litigation exposure and other costs	6	'	'
Claims resolution	'	14	'
Servicing fees	0	0	'
Management fees	0	0	'
Trading services	0	0	'
Securities finance	0	0	'
Processing fees and other	0	0	'
Total fee revenue	0	0	'
Net interest revenue	0	0	'
Gains (losses) related to investment securities, net	0	0	'
Total revenue	0	0	'
Provision for loan losses	0	0	'
Total expenses	111	14	'
Income before income tax expense	-111	-14	'
Total Average Assets	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Average assets	$215,600	$208,300	'

NonUS_Activities_Schedule_Of_R

Non-U.S. Activities (Schedule Of Results From Non-U.S. Operations) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Segment Reporting Information [Line Items]	'	'
Total fee revenue	$1,924	$1,857
Net interest revenue	555	576
Gains (losses) related to investment securities, net	6	2
Total revenue	2,485	2,435
Expenses	2,028	1,826
Income before income tax expense	455	609
Income tax expense	92	145
Net income	363	464
Non- U.S.	'	'
Segment Reporting Information [Line Items]	'	'
Total fee revenue	788	765
Net interest revenue	325	273
Gains (losses) related to investment securities, net	6	-3
Total revenue	1,119	1,035
Expenses	839	753
Income before income tax expense	280	282
Income tax expense	65	69
Net income	$215	$213

NonUS_Activities_Summary_Of_No

Non-U.S. Activities (Summary Of Non-U.S. Assets) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Segment Reporting Information [Line Items]	'	'
Interest-bearing deposits with banks	$75,796	$64,257
Other assets	23,989	25,990
Total assets	256,663	243,291
Non-U.S. Assets	'	'
Segment Reporting Information [Line Items]	'	'
Interest-bearing deposits with banks	10,281	9,584
Investment securities	31,790	31,522
Other assets	17,552	16,778
Total assets	$59,623	$57,884