Payable to return collateral related to interest rate swap assets

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Receivable for collateral posted related to interest rate swap liabilities

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Nominal or face amount used to calculate payment on derivative.

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Derivatives - Narrative (Details) $ in Millions	12 Months Ended
Derivatives - Narrative (Details) $ in Millions	Dec. 31, 2024 USD ($) swap	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of interest rate swaps entered into during the period \| swap	1
Gains (losses) on interest rate swaps expected to be reclassified from AOCI to net earnings over the next 12 months.	$ (8)
Interest rate swaps \| Designated as hedging instrument \| Net investment income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification from accumulated other comprehensive income	(24)	$ (26)	$ 0
Interest rate swaps \| Designated as hedging instrument \| Maximum \| Net investment income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification from accumulated other comprehensive income			$ 1
Interest rate swaps \| Cash flow hedging \| Designated as hedging instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount	1,050	1,300
Receivable for collateral posted related to swaps	27	48
New interest rate swaps entered during the period \| Cash flow hedging \| Designated as hedging instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount	20
Total return swap \| Derivatives not designated as hedging instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Receivable for collateral posted related to swaps	$ 4
Payable to return collateral related to swaps		$ 5