General - Schedule of condensed consolidated statements of cash flows (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net income	$ (321)	$ 650
Changes in:
Policy benefits and other insurance reserves	1,080	(111)
Unearned premiums	199	390
Deferred policy acquisition costs	(29)	(103)
Reinsurance recoverables, net	91	333
Income taxes	(125)	93
Other operating assets and liabilities	(87)	(574)
Net cash provided by operating activities	$ 601	432
As reported
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net income		646
Changes in:
Policy benefits and other insurance reserves		(113)
Unearned premiums		392
Deferred policy acquisition costs		(99)
Reinsurance recoverables, net		334
Income taxes		92
Other operating assets and liabilities		(574)
Net cash provided by operating activities		432
Impact of change
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net income		4
Changes in:
Policy benefits and other insurance reserves		2
Unearned premiums		(2)
Deferred policy acquisition costs		(4)
Reinsurance recoverables, net		(1)
Income taxes		1
Other operating assets and liabilities		0
Net cash provided by operating activities		$ 0