Goodwill and Other Intangibles - Narrative (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Intangible Asset, Goodwill and Other [Abstract]
Changes in the goodwill			$ 0
Goodwill	$ 327,000,000		327,000,000		$ 327,000,000
Amortizable intangible assets related to property and casualty insurance acquisitions	179,000,000		179,000,000		189,000,000
Accumulated amortization	85,000,000		85,000,000		$ 75,000,000
Amortization of intangible assets	$ 5,000,000	$ 5,000,000	$ 10,000,000	$ 10,000,000

Amount of amortization expense for finite-lived intangible asset. Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

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+ Details

- Definition

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

+ References

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+ Details