Loans, Lending Commitments and Related Allowance for Credit Losses - Allowance for Credit Losses Rollforward - Loans and Lending Commitments (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Allowance for loan losses rollforward
Beginning balance			$ 654	$ 835
Gross charge-offs			(17)	(102)
Recoveries			4
Net (charge-offs) recoveries			(13)
Provision (release)	$ 92	$ 16	131	(42)
Other			(10)	(4)
Ending balance	$ 762	$ 687	$ 762	$ 687
Percent of loans to total loans	100.00%	100.00%	100.00%	100.00%
Allowance for lending commitments rollforward
Beginning balance			$ 444	$ 396
Provision (release)	$ 9	$ 57	27	17
Other			(7)	(1)
Ending balance	464	412	464	412
Corporate
Allowance for loan losses rollforward
Beginning balance			165	309
Gross charge-offs			0	(14)
Recoveries			4
Net (charge-offs) recoveries			4
Provision (release)			47	(95)
Other			(4)	(1)
Ending balance	$ 212	$ 199	$ 212	$ 199
Percent of loans to total loans	3.00%	4.00%	3.00%	4.00%
Allowance for lending commitments rollforward
Beginning balance			$ 356	$ 323
Provision (release)			24	18
Other			(7)	(1)
Ending balance	$ 373	$ 340	373	340
Secured lending facilities
Allowance for loan losses rollforward
Beginning balance			163	198
Gross charge-offs			(3)	(67)
Recoveries			0
Net (charge-offs) recoveries			(3)
Provision (release)			8	48
Other			(1)	(2)
Ending balance	$ 167	$ 177	$ 167	$ 177
Percent of loans to total loans	17.00%	18.00%	17.00%	18.00%
Allowance for lending commitments rollforward
Beginning balance			$ 41	$ 38
Provision (release)			7	1
Other			0	1
Ending balance	$ 48	$ 40	48	40
Commercial real estate
Allowance for loan losses rollforward
Beginning balance			206	211
Gross charge-offs			(7)	(21)
Recoveries			0
Net (charge-offs) recoveries			(7)
Provision (release)			36	5
Other			(6)	(1)
Ending balance	$ 229	$ 194	$ 229	$ 194
Percent of loans to total loans	4.00%	5.00%	4.00%	5.00%
Allowance for lending commitments rollforward
Beginning balance			$ 20	$ 11
Provision (release)			(2)	0
Other			0	(1)
Ending balance	$ 18	$ 10	18	10
Residential real estate
Allowance for loan losses rollforward
Beginning balance			60	59
Gross charge-offs			0	0
Recoveries			0
Net (charge-offs) recoveries			0
Provision (release)			24	(2)
Other			0	0
Ending balance	$ 84	$ 57	$ 84	$ 57
Percent of loans to total loans	26.00%	25.00%	26.00%	25.00%
Allowance for lending commitments rollforward
Beginning balance			$ 1	$ 1
Provision (release)			1	0
Other			0	0
Ending balance	$ 2	$ 1	2	1
SBL and Other
Allowance for loan losses rollforward
Beginning balance			60	58
Gross charge-offs			(7)	0
Recoveries			0
Net (charge-offs) recoveries			(7)
Provision (release)			16	2
Other			1	0
Ending balance	$ 70	$ 60	$ 70	$ 60
Percent of loans to total loans	50.00%	48.00%	50.00%	48.00%
Allowance for lending commitments rollforward
Beginning balance			$ 26	$ 23
Provision (release)			(3)	(2)
Other			0	0
Ending balance	$ 23	$ 21	$ 23	$ 21

Amount of other addition (reduction) in allowance reserve for credit loss.

No definition available.

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- Definition

Financing Receivable, Loans Held for Investment by Loan Type to Total Loans Held for Investment

+ References

No definition available.

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- Definition

A valuation allowance for credit exposures related to off-balance-sheet loan commitments.

+ References

No definition available.

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- Definition

Other increase (decrease) in the allowance for credit exposures on off-balance-sheet loan commitments.

+ References

No definition available.

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- References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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- Definition

Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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- Definition

Amount, excluding accrued interest, of decrease (increase) in allowance for credit loss on financing receivable from writeoff (recovery). Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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- Definition

Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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