Deferred Policy Acquisition Costs - ASU 2018-12 Transition Deferred Acquisition Costs Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
ASU 2018-12
Deferred policy acquisition costs	$ 1,093	$ 1,013	$ 916	$ 838
Accounting Standards Update 2018-12
ASU 2018-12
Deferred policy acquisition costs		1,013		296
Effect of Modified Retrospective Application Accounting Standards Update 2018-12 | Accounting Standards Update 2018-12
ASU 2018-12
Deferred policy acquisition costs		(1)		33
Previously Reported | Accounting Standards Update 2018-12
ASU 2018-12
Deferred policy acquisition costs		$ 1,014		$ 263