Accounting Changes - Summary Of Impact Of Accounting Changes Due To Recogntion And Measurement Of Long Duration Insurance Contracts On The Cash Flow Statement (Detail) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
Disclosure In Tabular Form Of Impact Of Accounting Changes Due To Recogntion And Measurement Of Long Duration Insurance Contracts On The Cash Flow Statement [Line Items]
Net income	$ 168	$ 154	$ 197	$ 270	$ 322	$ 467
Adjustments to reconcile net income to net cash from operating activities:
Net investment (gains) losses	(39)		(19)		(28)	(61)
Changes in fair value of market risk benefits and associated hedges	$ (19)		20		(2)	(21)
Charges assessed to policyholders					(291)	(289)
Acquisition costs deferred					(4)	(7)
Amortization of deferred acquisition costs and intangibles					136	172
Deferred income taxes					107	143
Change in certain assets and liabilities:
Accrued investment income and other assets					(66)	(71)
Insurance reserves					525	641
Other liabilities, policy and contract claims and other policy-related balances					(165)	(382)
Net cash from operating activities					$ 275	337
Previously reported
Disclosure In Tabular Form Of Impact Of Accounting Changes Due To Recogntion And Measurement Of Long Duration Insurance Contracts On The Cash Flow Statement [Line Items]
Net income			219			398
Adjustments to reconcile net income to net cash from operating activities:
Net investment (gains) losses			(8)			(36)
Changes in fair value of market risk benefits and associated hedges			0			0
Charges assessed to policyholders						(292)
Acquisition costs deferred						(1)
Amortization of deferred acquisition costs and intangibles						176
Deferred income taxes						128
Change in certain assets and liabilities:
Accrued investment income and other assets						(70)
Insurance reserves						494
Other liabilities, policy and contract claims and other policy-related balances						(205)
Net cash from operating activities						337
Revision of prior periods | Accounting Standards Update 2018-12
Disclosure In Tabular Form Of Impact Of Accounting Changes Due To Recogntion And Measurement Of Long Duration Insurance Contracts On The Cash Flow Statement [Line Items]
Net income			(22)			69
Adjustments to reconcile net income to net cash from operating activities:
Net investment (gains) losses			(11)			(25)
Changes in fair value of market risk benefits and associated hedges			$ 20			(21)
Charges assessed to policyholders						3
Acquisition costs deferred						(6)
Amortization of deferred acquisition costs and intangibles						(4)
Deferred income taxes						15
Change in certain assets and liabilities:
Accrued investment income and other assets						(1)
Insurance reserves						147
Other liabilities, policy and contract claims and other policy-related balances						(177)
Net cash from operating activities						$ 0