FAIR VALUE MEASUREMENT - Valuation Techniques and Inputs for Level 3 Fair Value Measurements (Details)	Jun. 30, 2024 USD ($) year decimal	Dec. 31, 2023 USD ($) year decimal
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available-for-sale (AFS)	$ 249,362,000,000	$ 256,936,000,000
Marketable equity securities	696,000,000	766,000,000
Derivative assets	53,064,000,000	57,717,000,000
Mortgage-backed securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available-for-sale (AFS)	32,359,000,000	30,139,000,000
Model-based | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities borrowed and purchased under agreements to resell	126,000,000	139,000,000
State and municipal, foreign government, corporate and other debt securities		778,000,000
Marketable equity securities		38,000,000
Loans and leases	213,000,000	111,000,000
Mortgage servicing rights	63,000,000	66,000,000
Interest-bearing deposits	41,000,000	29,000,000
Securities loaned and sold under agreement to repurchase	286,000,000
Securities sold, not yet purchased and other trading liabilities	4,000,000
Short-term borrowings and long-term debt	20,111,000,000	38,794,000,000
Securities loaned or sold under agreements to repurchase		390,000,000
Securities loaned or sold under agreements to repurchase and other trading liabilities		5,000,000
Model-based | Level 3 | Interest rate contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	5,221,000,000	5,237,000,000
Model-based | Level 3 | Foreign exchange contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	1,766,000,000	1,652,000,000
Model-based | Level 3 | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	3,957,000,000	4,239,000,000
Model-based | Level 3 | Commodity and other contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	1,904,000,000	1,943,000,000
Model-based | Level 3 | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	973,000,000	1,135,000,000
Model-based | Level 3 | State And Municipal, Foreign Government, Corporate And Other Debt Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available-for-sale (AFS)	679,000,000
Price-based | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage-backed securities		679,000,000
State and municipal, foreign government, corporate and other debt securities		1,582,000,000
Marketable equity securities	230,000,000	259,000,000
Asset-backed securities	184,000,000	475,000,000
Non-marketable equities	90,000,000
Derivative assets	734,000,000
Nontrading derivatives and other financial assets and liabilities measured on a recurring basis (gross)	24,000,000	36,000,000
Loans and leases	88,000,000	316,000,000
Securities sold, not yet purchased and other trading liabilities	25,000,000
Securities loaned or sold under agreements to repurchase and other trading liabilities		23,000,000
Price-based | Level 3 | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	713,000,000
Price-based | Level 3 | Mortgage-backed securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available-for-sale (AFS)	423,000,000
Price-based | Level 3 | State And Municipal, Foreign Government, Corporate And Other Debt Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available-for-sale (AFS)	999,000,000
Yield analysis | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage-backed securities		401,000,000
Asset-backed securities	61,000,000	57,000,000
Securities loaned or sold under agreements to repurchase and other trading liabilities		7,000,000
Yield analysis | Level 3 | Mortgage-backed securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available-for-sale (AFS)	559,000,000
Comparables analysis | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities	310,000,000	366,000,000
Cash flow | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities	57,000,000	56,000,000
Mortgage servicing rights	$ 615,000,000	$ 595,000,000
Minimum | Model-based | Level 3 | Credit spread
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities borrowed and purchased under agreements to resell	0.0011	0.0015
State and municipal, foreign government, corporate and other debt securities		0.0035
Minimum | Model-based | Level 3 | Credit spread | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.0011	0.001143
Minimum | Model-based | Level 3 | Credit spread | State And Municipal, Foreign Government, Corporate And Other Debt Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities, measurement input	0.0035
Minimum | Model-based | Level 3 | Interest rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities borrowed and purchased under agreements to resell	0.0485	0.0400
Securities loaned and sold under agreement to repurchase	0.0434
Securities loaned and sold under agreements to repurchase		0.0392
Minimum | Model-based | Level 3 | Interest rate | Interest rate contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.0306	0.0270
Minimum | Model-based | Level 3 | Price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities sold, not yet purchased and other trading liabilities	0
Minimum | Model-based | Level 3 | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights		0
Minimum | Model-based | Level 3 | WAL
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Marketable equity securities | year		2.24
Minimum | Model-based | Level 3 | WAL | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets | year	2.91	2.24
Minimum | Model-based | Level 3 | Recovery (in millions)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Marketable equity securities		7,398,000,000
Derivative assets	7,723,000,000
Minimum | Model-based | Level 3 | Recovery (in millions) | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		7,398,000,000
Minimum | Model-based | Level 3 | IR normal volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Short-term borrowings and long-term debt	0.0005	0.0032
Minimum | Model-based | Level 3 | IR normal volatility | Interest rate contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.0034	(0.0007)
Minimum | Model-based | Level 3 | IR normal volatility | Foreign exchange contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.0043	(0.0007)
Minimum | Model-based | Level 3 | IR basis | Foreign exchange contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	(0.0145)	(0.0145)
Minimum | Model-based | Level 3 | FX volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	(0.9500)
Securities loaned or sold under agreements to repurchase and other trading liabilities, measurement		0.0356
Minimum | Model-based | Level 3 | Equity volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases	0.1846	0.4161
Interest-bearing deposits	1.0000
Short-term borrowings and long-term debt	0.0005
Minimum | Model-based | Level 3 | Equity volatility | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.0005	0.0010
Minimum | Model-based | Level 3 | Equity forward
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases	0.3606
Minimum | Model-based | Level 3 | Equity forward | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.6775	0.5414
Minimum | Model-based | Level 3 | Equity-FX correlation | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		(0.7900)
Minimum | Model-based | Level 3 | Forward price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases		0.3348
Interest-bearing deposits	1.0744	1.0000
Short-term borrowings and long-term debt	0.6775
Minimum | Model-based | Level 3 | Forward price | Commodity and other contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.1140	0.3170
Minimum | Model-based | Level 3 | Commodity volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases		0.2651
Minimum | Model-based | Level 3 | Commodity volatility | Commodity and other contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.0853	0.1472
Minimum | Model-based | Level 3 | Recovery rate | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.1000	0.1500
Minimum | Model-based | Level 3 | Commodity correlation
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases		(0.4533)
Minimum | Model-based | Level 3 | Commodity correlation | Commodity and other contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		(0.4533)
Minimum | Model-based | Level 3 | Upfront points | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.0099
Minimum | Model-based | Level 3 | Equity-Equity correlation | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	(0.3622)	(0.0649)
Short-term borrowings and long-term debt	(0.4000)
Minimum | Model-based | Level 3 | Credit spread volatility | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		0.2394
Minimum | Price-based | Level 3 | Price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage-backed securities		1.67
State and municipal, foreign government, corporate and other debt securities		0.01
Marketable equity securities		0
Marketable equity securities	0
Asset-backed securities		3.50
Asset-backed securities	1.30
Non-marketable equities	0.55
Non-marketable equities		0.40
Derivative assets	79.11
Nontrading derivatives and other financial assets and liabilities measured on a recurring basis (gross)	0.11	0.01
Loans and leases	77.24	98.80
Securities sold, not yet purchased and other trading liabilities
Securities Loaned Or Sold Under Agreements To Repurchase And Other Trading Liabilities, Measurement Input, Value		0
Minimum | Price-based | Level 3 | Price | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		$ 378,000,000
Derivative assets	46.28
Derivative assets		37.67
Minimum | Price-based | Level 3 | Price | Mortgage-backed securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities, measurement input	0.18
Minimum | Price-based | Level 3 | Price | State And Municipal, Foreign Government, Corporate And Other Debt Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities, measurement input	0
Minimum | Price-based | Level 3 | Revenue multiple
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities		$ 50,000,000
Minimum | Price-based | Level 3 | Upfront points | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		0.0125
Minimum | Yield analysis | Level 3 | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage-backed securities		0.0463
Asset-backed securities	0.0619	0.0593
Securities loaned or sold under agreements to repurchase and other trading liabilities, measurement		0.0746
Minimum | Yield analysis | Level 3 | Yield | Mortgage-backed securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities, measurement input	0.0491
Minimum | Comparables analysis | Level 3 | Illiquidity discount
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities	0.0740	0.0800
Minimum | Comparables analysis | Level 3 | Revenue multiple
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities | decimal	3.26	2.80
Minimum | Comparables analysis | Level 3 | PE ratio
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities | decimal	8.30	9.30
Minimum | Comparables analysis | Level 3 | EBITDA multiples
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities | decimal		15.80
Minimum | Cash flow | Level 3 | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights	(0.0050)
Minimum | Cash flow | Level 3 | WAL
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights | year	3.68	1.00
Minimum | Cash flow | Level 3 | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities	0.0925	0.0850
Maximum | Model-based | Level 3 | Credit spread
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities borrowed and purchased under agreements to resell	0.0630	0.0015
State and municipal, foreign government, corporate and other debt securities		0.0550
Maximum | Model-based | Level 3 | Credit spread | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.0630	0.1519
Maximum | Model-based | Level 3 | Credit spread | State And Municipal, Foreign Government, Corporate And Other Debt Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities, measurement input	0.0550
Maximum | Model-based | Level 3 | Interest rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities borrowed and purchased under agreements to resell	0.0485	0.0400
Securities loaned and sold under agreement to repurchase	0.0526
Securities loaned and sold under agreements to repurchase		0.0527
Maximum | Model-based | Level 3 | Interest rate | Interest rate contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.0534	0.0540
Maximum | Model-based | Level 3 | Price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities sold, not yet purchased and other trading liabilities	14,233.69
Maximum | Model-based | Level 3 | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights		0.1200
Maximum | Model-based | Level 3 | WAL
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Marketable equity securities | year		2.24
Maximum | Model-based | Level 3 | WAL | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets | year	2.91	2.24
Maximum | Model-based | Level 3 | Recovery (in millions)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Marketable equity securities		7,398,000,000
Derivative assets	7,723,000,000
Maximum | Model-based | Level 3 | Recovery (in millions) | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		7,398,000,000
Maximum | Model-based | Level 3 | IR normal volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Short-term borrowings and long-term debt	0.2000	0.2000
Maximum | Model-based | Level 3 | IR normal volatility | Interest rate contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.2000	0.1500
Maximum | Model-based | Level 3 | IR normal volatility | Foreign exchange contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.0120	0.1205
Maximum | Model-based | Level 3 | IR basis | Foreign exchange contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	1.1148	1.4779
Maximum | Model-based | Level 3 | FX volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.7000
Securities loaned or sold under agreements to repurchase and other trading liabilities, measurement		0.2813
Maximum | Model-based | Level 3 | Equity volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases	3.2135	0.4540
Interest-bearing deposits	1.0000
Short-term borrowings and long-term debt	2.8865
Maximum | Model-based | Level 3 | Equity volatility | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	2.8865	3.3435
Maximum | Model-based | Level 3 | Equity forward
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases	0.4099
Maximum | Model-based | Level 3 | Equity forward | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	2.1394	2.7354
Maximum | Model-based | Level 3 | Equity-FX correlation | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		0.7000
Maximum | Model-based | Level 3 | Forward price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases		3.4843
Interest-bearing deposits	1.1428	1.0000
Short-term borrowings and long-term debt	2.1394
Maximum | Model-based | Level 3 | Forward price | Commodity and other contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	3.8073	4.2551
Maximum | Model-based | Level 3 | Commodity volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases		0.6680
Maximum | Model-based | Level 3 | Commodity volatility | Commodity and other contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	1.9955	1.4999
Maximum | Model-based | Level 3 | Recovery rate | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.4000	0.7500
Maximum | Model-based | Level 3 | Commodity correlation
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases		0.9302
Maximum | Model-based | Level 3 | Commodity correlation | Commodity and other contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		0.9302
Maximum | Model-based | Level 3 | Upfront points | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	1.1439
Maximum | Model-based | Level 3 | Equity-Equity correlation | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.9925	0.9744
Short-term borrowings and long-term debt	0.5000
Maximum | Model-based | Level 3 | Credit spread volatility | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		1.1566
Maximum | Price-based | Level 3 | Price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage-backed securities		124.63
State and municipal, foreign government, corporate and other debt securities		123.74
Marketable equity securities		12,189.17
Marketable equity securities	14,233.69
Asset-backed securities		129.00
Asset-backed securities	629.46
Non-marketable equities	164.44
Non-marketable equities		158.92
Derivative assets	98.20
Nontrading derivatives and other financial assets and liabilities measured on a recurring basis (gross)	413.66	104.79
Loans and leases	98.66	98.80
Securities sold, not yet purchased and other trading liabilities
Securities Loaned Or Sold Under Agreements To Repurchase And Other Trading Liabilities, Measurement Input, Value		12,189.17
Maximum | Price-based | Level 3 | Price | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	97.01
Derivative assets		97.00
Maximum | Price-based | Level 3 | Price | Mortgage-backed securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities, measurement input	133.77
Maximum | Price-based | Level 3 | Price | State And Municipal, Foreign Government, Corporate And Other Debt Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities, measurement input	185.42
Maximum | Price-based | Level 3 | Upfront points | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		1.1731
Maximum | Yield analysis | Level 3 | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage-backed securities		0.1908
Asset-backed securities	0.1226	0.1886
Securities loaned or sold under agreements to repurchase and other trading liabilities, measurement		0.0746
Maximum | Yield analysis | Level 3 | Yield | Mortgage-backed securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities, measurement input	0.1618
Maximum | Comparables analysis | Level 3 | Illiquidity discount
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities	0.3300	0.1000
Maximum | Comparables analysis | Level 3 | Revenue multiple
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities | decimal	15.46	13.40
Maximum | Comparables analysis | Level 3 | PE ratio
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities | decimal	8.30	16.50
Maximum | Comparables analysis | Level 3 | EBITDA multiples
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities | decimal		15.80
Maximum | Cash flow | Level 3 | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights	0.1200
Maximum | Cash flow | Level 3 | WAL
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights | year	8.62	8.76
Maximum | Cash flow | Level 3 | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities	0.1750	0.0850
Weighted Average | Model-based | Level 3 | Credit spread
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities borrowed and purchased under agreements to resell	0.0108	0.0015
State and municipal, foreign government, corporate and other debt securities		0.0304
Weighted Average | Model-based | Level 3 | Credit spread | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.0089	0.014034
Weighted Average | Model-based | Level 3 | Credit spread | State And Municipal, Foreign Government, Corporate And Other Debt Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities, measurement input	0.0273
Weighted Average | Model-based | Level 3 | Interest rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities borrowed and purchased under agreements to resell	0.0485	0.0400
Securities loaned and sold under agreement to repurchase	0.0452
Securities loaned and sold under agreements to repurchase		0.0396
Weighted Average | Model-based | Level 3 | Interest rate | Interest rate contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.0359	0.0320
Weighted Average | Model-based | Level 3 | Price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities sold, not yet purchased and other trading liabilities	200.05
Weighted Average | Model-based | Level 3 | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights		0.0806
Weighted Average | Model-based | Level 3 | WAL
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Marketable equity securities | year		2.24
Weighted Average | Model-based | Level 3 | WAL | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets | year	2.91	2.24
Weighted Average | Model-based | Level 3 | Recovery (in millions)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Marketable equity securities		7,398,000,000
Derivative assets	7,723,000,000
Weighted Average | Model-based | Level 3 | Recovery (in millions) | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		7,398,000,000
Weighted Average | Model-based | Level 3 | IR normal volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Short-term borrowings and long-term debt	0.0153	0.0125
Weighted Average | Model-based | Level 3 | IR normal volatility | Interest rate contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.0221	0.0144
Weighted Average | Model-based | Level 3 | IR normal volatility | Foreign exchange contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.0082	0.0150
Weighted Average | Model-based | Level 3 | IR basis | Foreign exchange contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.0424	0.0711
Weighted Average | Model-based | Level 3 | FX volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	(0.0637)
Securities loaned or sold under agreements to repurchase and other trading liabilities, measurement		0.1317
Weighted Average | Model-based | Level 3 | Equity volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases	1.0861	0.4317
Interest-bearing deposits	1.0000
Short-term borrowings and long-term debt	0.3569
Weighted Average | Model-based | Level 3 | Equity volatility | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.3928	0.3835
Weighted Average | Model-based | Level 3 | Equity forward
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases	0.3746
Weighted Average | Model-based | Level 3 | Equity forward | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	1.0683	1.0144
Weighted Average | Model-based | Level 3 | Equity-FX correlation | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		(0.0766)
Weighted Average | Model-based | Level 3 | Forward price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases		1.1547
Interest-bearing deposits	1.1170	1.0000
Short-term borrowings and long-term debt	1.0671
Weighted Average | Model-based | Level 3 | Forward price | Commodity and other contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	1.1720	1.3465
Weighted Average | Model-based | Level 3 | Commodity volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases		0.3179
Weighted Average | Model-based | Level 3 | Commodity volatility | Commodity and other contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.3060	0.3703
Weighted Average | Model-based | Level 3 | Recovery rate | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.3682	0.3656
Weighted Average | Model-based | Level 3 | Commodity correlation
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases		(0.0728)
Weighted Average | Model-based | Level 3 | Commodity correlation | Commodity and other contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		0.4503
Weighted Average | Model-based | Level 3 | Upfront points | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.5052
Weighted Average | Model-based | Level 3 | Equity-Equity correlation | Equity contracts (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	0.7129	0.8042
Short-term borrowings and long-term debt	0.2804
Weighted Average | Model-based | Level 3 | Credit spread volatility | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		0.4276
Weighted Average | Price-based | Level 3 | Price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage-backed securities		55.39
State and municipal, foreign government, corporate and other debt securities		79.71
Marketable equity securities		168.09
Marketable equity securities	430.77
Asset-backed securities		65.87
Asset-backed securities	96.20
Non-marketable equities	65.60
Non-marketable equities		56.78
Derivative assets	97.60
Nontrading derivatives and other financial assets and liabilities measured on a recurring basis (gross)	130.88	90.87
Loans and leases	86.08	98.80
Securities sold, not yet purchased and other trading liabilities
Securities Loaned Or Sold Under Agreements To Repurchase And Other Trading Liabilities, Measurement Input, Value		28.70
Weighted Average | Price-based | Level 3 | Price | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	83.66
Derivative assets		79.54
Weighted Average | Price-based | Level 3 | Price | Mortgage-backed securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities, measurement input	34.29
Weighted Average | Price-based | Level 3 | Price | State And Municipal, Foreign Government, Corporate And Other Debt Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities, measurement input	88.69
Weighted Average | Price-based | Level 3 | Upfront points | Credit derivatives (gross)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets		0.5810
Weighted Average | Yield analysis | Level 3 | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage-backed securities		0.0893
Asset-backed securities	0.0844	0.0857
Securities loaned or sold under agreements to repurchase and other trading liabilities, measurement		0.0746
Weighted Average | Yield analysis | Level 3 | Yield | Mortgage-backed securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities, measurement input	0.0794
Weighted Average | Comparables analysis | Level 3 | Illiquidity discount
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities	0.1396	0.0882
Weighted Average | Comparables analysis | Level 3 | Revenue multiple
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities | decimal	10.68	12.28
Weighted Average | Comparables analysis | Level 3 | PE ratio
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities | decimal	8.30	11.37
Weighted Average | Comparables analysis | Level 3 | EBITDA multiples
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities | decimal		15.80
Weighted Average | Cash flow | Level 3 | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights	0.0622
Weighted Average | Cash flow | Level 3 | WAL
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights | year	7.52	1.29
Weighted Average | Cash flow | Level 3 | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Non-marketable equities	0.1255	0.0850