Derivative Financial Instruments - Additional Information (Detail) - USD ($)	Jun. 30, 2024	Dec. 31, 2023
Derivative Instruments Gain Loss [Line Items]
Decrease in valuation due to net credit risk adjustments	$ 3,000,000	$ 5,000,000
Decrease in valuation due to liquidity adjustments	400,000	1,000,000
Derivative liability at fair value including accrued interest and premium receivable	230,000,000	197,000,000
Net positive exposure related to corporate derivatives	7,000,000	6,000,000
Net positive exposure on foreign currency swaps	0	$ 0
Counterparty [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative liability at fair value including accrued interest and premium receivable	$ 0

Decrease in valuation due to liquidity adjustments.

No definition available.

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- Definition

Amount of credit risk valuation adjustment to derivative assets to properly reflect the credit quality of the counterparties.

+ References

No definition available.

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- 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
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-8

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4E
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4E

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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
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4H

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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
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-SubTopic 10
-Topic 815
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480463/815-10-45-5

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