Guarantee Arrangements, Pledged Assets and Repurchase Agreements - Net Credit Derivative Positions (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Credit Derivatives [Line Items]
Net position, Carrying/Fair Value	$ (55)	$ 70
Notional	2,675	13,611
Sell-protection credit derivative positions
Credit Derivatives [Line Items]
Carrying/Fair Value	7	144
Notional	2,174	19,500
Buy-protection credit derivative positions
Credit Derivatives [Line Items]
Carrying/Fair Value	(62)	(74)
Notional	$ 4,849	$ 33,111

Maximum potential amount of future undiscounted payments that could be required under the credit derivative, before reduction for potential recoveries under recourse or collateralization provisions.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4K
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5708775-113959

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Fair value of credit risk derivative asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4K
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5708775-113959

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- Definition

Fair value of credit risk derivative liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4K
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- Definition

Fair value of credit risk derivative asset after deduction of credit risk derivative liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4K
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5708775-113959

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