Derivative Instruments - Liquidity Risk and Credit-Related Contingent Features (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
OTC and OTC-cleared derivative payables containing downgrade triggers
Aggregate fair value of net derivative payables	$ 27,712	$ 14,819
Collateral posted	26,289	13,329
Single-notch downgrade
Liquidity impact of downgrade triggers on OTC and OTC-cleared derivatives
Amount of additional collateral to be posted upon downgrade	119	189
Amount required to settle contracts with termination triggers upon downgrade	153	104
Two-notch downgrade
Liquidity impact of downgrade triggers on OTC and OTC-cleared derivatives
Amount of additional collateral to be posted upon downgrade	1,243	1,467
Amount required to settle contracts with termination triggers upon downgrade	$ 2,449	$ 1,398

Liquidity Impact of Downgrade Triggers on OTC and OTC-Cleared Derivatives [Abstract]

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- Definition

OTC and OTC-Cleared Derivative Payables Containing Downgrade Triggers [Abstract]

+ References

No definition available.

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- Definition

The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624258-113959

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- Definition

The aggregate fair value of assets needed to immediately settle the derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624258-113959

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624258-113959

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624258-113959

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