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Derivatives - Narrative (Details) $ in Millions	3 Months Ended
Derivatives - Narrative (Details) $ in Millions	Mar. 31, 2026 USD ($) swap	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of interest rate swaps entered during the period \| swap	4
Gains (losses) on interest rate swaps expected to be reclassified from AOCI to net earnings over the next 12 months.	$ 3
Interest rate swaps \| Designated as hedging instrument \| Net investment income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification from accumulated other comprehensive income	(1)	$ (3)
Interest rate swaps \| Cash flow hedging \| Designated as hedging instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount	714		$ 464
Collateral receivable supporting swaps	16		10
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	300
Total return swap \| Not designated as hedging instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Collateral receivable supporting swaps	$ 10
Total return swap \| Not designated as hedging instrument \| Maximum
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Liability to return collateral related to swaps			$ 1