Deferred Policy Acquisition Costs - Deferred Policy Acquisition Costs and Asset Reconciliation (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Movement Analysis of Deferred Policy Acquisition Costs
Deferred policy acquisition costs asset, beginning of period	$ 1,013	$ 916
Capitalized deferred policy acquisition costs	383	376
Amortized deferred policy acquisition costs	(348)	(308)
Deferred policy acquisition costs asset, end of period	1,048	984
Consolidated Property And Casualty Insurance
Movement Analysis of Deferred Policy Acquisition Costs
Deferred policy acquisition costs asset, beginning of period	682	602
Capitalized deferred policy acquisition costs	372	364
Amortized deferred policy acquisition costs	(340)	(301)
Deferred policy acquisition costs asset, end of period	714	665
Life Insurance Segment
Movement Analysis of Deferred Policy Acquisition Costs
Deferred policy acquisition costs asset, beginning of period	331	314
Capitalized deferred policy acquisition costs	11	12
Amortized deferred policy acquisition costs	(8)	(7)
Deferred policy acquisition costs asset, end of period	$ 334	$ 319