Goodwill and Other Intangibles - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Changes in the goodwill			$ 0
Goodwill	$ 305,000,000		305,000,000		$ 305,000,000
Amortizable intangible assets related to property and casualty insurance acquisitions	204,000,000		204,000,000		213,000,000
Accumulated amortization	48,000,000		48,000,000		$ 39,000,000
Amortization of intangible assets	$ 4,000,000	$ 3,000,000	$ 9,000,000	$ 6,000,000