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Derivative Financial Instruments - Credit Exposure Related Counterparties (Detail) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Derivative Instruments Gain Loss [Line Items]
Exposure, net of collateral	$ 14	$ 13
Exposure, net of collateral	13	$ 28
Corporate Contracts [Member]
Derivative Instruments Gain Loss [Line Items]
Exposure, net of collateral	$ 14
Percent of exposure to counterparties with credit ratings below S&P AA- or Moody’s Aa3	100.00%
Percent of exposure to counterparties with credit ratings below S&P A- or Moody’s A3	17.00%
Securitization Trust Contracts [Member]
Derivative Instruments Gain Loss [Line Items]
Exposure, net of collateral	$ 13

X

- Definition

Percent Of Exposure To Counterparties With Credit Ratings Below S&P AA Or Moody Aa3.

+ References

No definition available.

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- Definition

Percent Of Exposure To Counterparties With Credit Ratings Below S&P A Or Moody A3.

+ References

No definition available.

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X

- Definition

The net amount as of the balance sheet date of the fair value of derivative assets and derivative liabilities that in accordance with the entity's accounting policy were offset against collateral under a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=d3e41678-113959

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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 as of the balance sheet date of all derivatives designated as foreign currency fair value hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=117331979&loc=d3e41228-113958

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