Goodwill and Other Intangibles - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Goodwill and Intangible Assets Disclosure [Abstract]
Changes in the goodwill	$ 0
Goodwill	305,000,000		$ 305,000,000
Amortizable intangible assets related to property and casualty insurance acquisitions	198,000,000		203,000,000
Accumulated amortization	64,000,000		$ 59,000,000
Amortization of intangible assets	$ 5,000,000	$ 5,000,000