Derivative Financial Instruments - Fair value of instruments with credit-risk-contingent features (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Gross liability fair value of contracts containing credit-risk-contingent features	$ 7,000,000	$ 19,000,000
Gross asset fair value of contracts containing credit-risk-contingent features and subject to MNAs	(6,000,000)	(6,000,000)
Collateral posted under MNAs for contracts containing credit-risk-contingent features	0	(13,000,000)
Maximum amount of additional exposure for contracts with credit-risk-contingent features if all features were triggered concurrently	$ 1,000,000	$ 0

Fair value of derivative asset, presented on a gross basis containing credit risk contingent features and which is subject to master netting arrangements.

No definition available.

+ Details

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- Definition

Fair value of derivative liabilities, presented on a gross basis containing credit risk contingent features.

+ References

No definition available.

+ Details

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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=125515794&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=125515794&loc=SL5624258-113959

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- References

No definition available.

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