Derivative Instruments and Hedging Activities - Derivative Assets and Liabilities at Fair Value (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Notional or contractual amount	$ 282,510	$ 227,801
Derivative assets, gross amount	2,745	3,098
Derivative liabilities, gross amount	3,556	4,550
Derivative asset, netting adjustments	(1,250)	(1,134)
Derivative liability, netting adjustments	(717)	(1,235)
Total derivative assets	1,495	1,964
Total derivative liabilities	2,839	3,315
Net valuation allowance on derivative assets and liabilities for non-performance risk	2	4
Prepayable Financial Asset Closed Portfolio, Last-of-Layer, Amortized Cost	365	225
Derivatives designated as accounting hedges
Derivatives, Fair Value [Line Items]
Notional or contractual amount	128,789	98,966
Derivative assets, gross amount	71	85
Derivative liabilities, gross amount	466	820
Derivatives designated as accounting hedges | Interest rate contracts
Derivatives, Fair Value [Line Items]
Notional or contractual amount	120,325	91,306
Derivative assets, gross amount	70	3
Derivative liabilities, gross amount	57	504
Derivatives designated as accounting hedges | Interest rate contracts | Fair value hedges
Derivatives, Fair Value [Line Items]
Notional or contractual amount	67,225	60,956
Derivative assets, gross amount	6	3
Derivative liabilities, gross amount	25	53
Derivatives designated as accounting hedges | Interest rate contracts | Cash flow hedges
Derivatives, Fair Value [Line Items]
Notional or contractual amount	53,100	30,350
Derivative assets, gross amount	64	0
Derivative liabilities, gross amount	32	451
Derivatives designated as accounting hedges | Foreign exchange contracts
Derivatives, Fair Value [Line Items]
Notional or contractual amount	8,464	7,660
Derivative assets, gross amount	1	82
Derivative liabilities, gross amount	409	316
Derivatives designated as accounting hedges | Foreign exchange contracts | Fair value hedges
Derivatives, Fair Value [Line Items]
Notional or contractual amount	1,364	1,338
Derivative assets, gross amount	0	0
Derivative liabilities, gross amount	176	211
Derivatives designated as accounting hedges | Foreign exchange contracts | Cash flow hedges
Derivatives, Fair Value [Line Items]
Notional or contractual amount	2,340	2,175
Derivative assets, gross amount	1	4
Derivative liabilities, gross amount	34	14
Derivatives designated as accounting hedges | Foreign exchange contracts | Net investment hedges
Derivatives, Fair Value [Line Items]
Notional or contractual amount	4,760	4,147
Derivative assets, gross amount	0	78
Derivative liabilities, gross amount	199	91
Derivatives not designated as accounting hedges
Derivatives, Fair Value [Line Items]
Notional or contractual amount	153,721	128,835
Derivative assets, gross amount	2,674	3,013
Derivative liabilities, gross amount	3,090	3,730
Derivatives not designated as accounting hedges | Customer accommodation
Derivatives, Fair Value [Line Items]
Notional or contractual amount	150,112	125,462
Derivative assets, gross amount	2,638	2,970
Derivative liabilities, gross amount	3,059	3,689
Derivatives not designated as accounting hedges | Interest rate contracts | Customer accommodation
Derivatives, Fair Value [Line Items]
Notional or contractual amount	116,019	91,601
Derivative assets, gross amount	1,523	1,140
Derivative liabilities, gross amount	1,921	1,873
Derivatives not designated as accounting hedges | Interest rate contracts | Other interest rate exposures
Derivatives, Fair Value [Line Items]
Notional or contractual amount	999	1,135
Derivative assets, gross amount	23	34
Derivative liabilities, gross amount	14	22
Derivatives not designated as accounting hedges | Foreign exchange contracts | Customer accommodation
Derivatives, Fair Value [Line Items]
Notional or contractual amount	4,585	4,926
Derivative assets, gross amount	51	74
Derivative liabilities, gross amount	45	78
Derivatives not designated as accounting hedges | Commodity contracts | Customer accommodation
Derivatives, Fair Value [Line Items]
Notional or contractual amount	29,508	28,935
Derivative assets, gross amount	1,064	1,756
Derivative liabilities, gross amount	1,093	1,738
Derivatives not designated as accounting hedges | Other contracts
Derivatives, Fair Value [Line Items]
Notional or contractual amount	2,610	2,238
Derivative assets, gross amount	13	9
Derivative liabilities, gross amount	$ 17	$ 19