Fair Values - Activity of Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - Recurring - Level 3 - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021
Liabilities at Fair Value
Portion of Unrealized losses (gains) recorded in OCI—Change in net DVA	$ (29)		$ (29)
Deposits
Liabilities at Fair Value
Beginning balance	67		126
Realized and unrealized losses (gains)	0		(4)
Issuances	0		11
Settlements	(5)		(2)
Net transfers	(36)		46
Ending balance	26	$ 67	177
Unrealized losses (gains)	0		(4)
Nonderivative trading liabilities
Liabilities at Fair Value
Beginning balance	61		79
Realized and unrealized losses (gains)	(3)		(9)
Purchases	(33)		(20)
Sales	11		13
Net transfers	12		(1)
Ending balance	48	61	62
Unrealized losses (gains)	(3)		(9)
Securities sold under agreements to repurchase
Liabilities at Fair Value
Beginning balance	651		444
Realized and unrealized losses (gains)	2		(2)
Settlements	(10)		0
Net transfers	(127)		(1)
Ending balance	516	651	441
Unrealized losses (gains)	2		(2)
Other secured financings
Liabilities at Fair Value
Beginning balance	403		516
Realized and unrealized losses (gains)	(3)		(5)
Issuances	28		370
Settlements	(305)		(322)
Net transfers	(3)		(4)
Ending balance	120	403	555
Unrealized losses (gains)	(3)		(5)
Borrowings
Liabilities at Fair Value
Beginning balance	2,157		4,374
Realized and unrealized losses (gains)	(143)		(118)
Issuances	161		231
Settlements	(42)		(316)
Net transfers	266		91
Ending balance	2,399	2,157	4,262
Unrealized losses (gains)	(143)		(116)
Interest rate
Assets at Fair value
Beginning balance	708		682
Realized and unrealized gains (losses)	39		(413)
Purchases	3		31
Issuances	(2)		(17)
Settlements	(21)		83
Net transfers	(93)		325
Ending balance	634	708	691
Unrealized gains (losses)	147		(403)
Credit
Assets at Fair value
Beginning balance	98		49
Realized and unrealized gains (losses)	43		(4)
Purchases	8		19
Issuances	(8)		(8)
Settlements	(68)		(72)
Net transfers	20		(66)
Ending balance	93	98	(82)
Unrealized gains (losses)	28		(13)
Foreign exchange
Assets at Fair value
Beginning balance	52		61
Realized and unrealized gains (losses)	(145)		(236)
Purchases	5		2
Issuances	0		(4)
Settlements	81		26
Net transfers	(26)		41
Ending balance	(33)	52	(110)
Unrealized gains (losses)	(138)		(206)
Equity
Assets at Fair value
Beginning balance	(945)		(2,231)
Realized and unrealized gains (losses)	98		63
Purchases	28		77
Issuances	(68)		(297)
Settlements	117		65
Net transfers	116		206
Ending balance	(654)	(945)	(2,117)
Unrealized gains (losses)	88		12
Commodity and other
Assets at Fair value
Beginning balance	1,529		1,709
Realized and unrealized gains (losses)	4		331
Purchases	9		7
Issuances	(11)		(1)
Settlements	(47)		(131)
Net transfers	(50)		29
Ending balance	1,434	1,529	1,944
Unrealized gains (losses)	(216)		215
U.S. Treasury and agency securities
Assets at Fair value
Beginning balance	2		9
Purchases	1		12
Sales	0		(9)
Net transfers	5		0
Ending balance	8	2	12
Unrealized gains (losses)	0		0
Other sovereign government obligations
Assets at Fair value
Beginning balance	211		268
Purchases	6		15
Sales	(40)		(256)
Net transfers	11		(10)
Ending balance	188	211	17
Unrealized gains (losses)	0		0
State and municipal securities
Assets at Fair value
Beginning balance	13		0
Net transfers	(13)		0
Ending balance	0	13	0
Unrealized gains (losses)	0		0
MABS
Assets at Fair value
Beginning balance	344		322
Realized and unrealized gains (losses)	(1)		51
Purchases	56		144
Sales	(96)		(103)
Net transfers	48		(40)
Ending balance	351	344	374
Unrealized gains (losses)	(3)		(2)
Loans and lending commitments
Assets at Fair value
Beginning balance	3,806		5,759
Realized and unrealized gains (losses)	26		(26)
Purchases and originations	369		1,833
Sales	(210)		(2,060)
Settlements	(409)		(388)
Net transfers	(441)		(73)
Ending balance	3,141	3,806	5,045
Unrealized gains (losses)	22		(32)
Corporate and other debt
Assets at Fair value
Beginning balance	1,973		3,435
Realized and unrealized gains (losses)	12		(51)
Purchases and originations	71		867
Sales	(160)		(749)
Settlements	0		(255)
Net transfers	(143)		72
Ending balance	1,753	1,973	3,319
Unrealized gains (losses)	7		2
Corporate equities
Assets at Fair value
Beginning balance	115		86
Realized and unrealized gains (losses)	0		16
Purchases	24		25
Sales	(82)		(46)
Net transfers	182		33
Ending balance	239	115	114
Unrealized gains (losses)	0		18
Investments
Assets at Fair value
Beginning balance	1,125		828
Realized and unrealized gains (losses)	(24)		6
Purchases	20		64
Sales	(4)		(15)
Net transfers	3		41
Ending balance	1,120	1,125	924
Unrealized gains (losses)	(26)		(6)
Investment securities —AFS
Assets at Fair value
Beginning balance	0		2,804
Realized and unrealized gains (losses)	0		(4)
Sales	0		(192)
Net transfers	0		(2,481)
Ending balance	0	0	127
Unrealized gains (losses)	0		(5)
Liabilities at Fair Value
Transfers from Level 3 to Level 2		2,500
Securities purchased under agreements to resell
Assets at Fair value
Beginning balance	0		3
Net transfers	0		(3)
Ending balance	0	$ 0	0
Unrealized gains (losses)	$ 0		$ 0

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases and Originations

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Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held.

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Amount of unrealized gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3) and still held.

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

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Amount of gain (loss) recognized in other comprehensive income (OCI) from liability measured at fair value on recurring basis using unobservable input (level 3).

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Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy.

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