Acquisitions and Sale of Businesses - Impact of exited lines on earnings (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Jun. 30, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net investment income			$ 730	$ 461	$ 532
Net earnings, including noncontrolling interests			1,995	721	869
Realized gains on subsidiaries			4	23	0
Income tax expense (benefit)			(254)	(25)	(143)
Less: Net loss attributable to noncontrolling interests			$ 0	11	28
Neon Capital Limited
Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Underwriting loss				(135)	(36)
Net investment income				(5)	6
Other income and expenses, net				(5)	(10)
Net earnings, including noncontrolling interests				(145)	$ (40)
Realized gains on subsidiaries	$ 4	$ 23		23
Total pretax loss from Neon exited lines				(122)
Income tax expense (benefit)				72
Less: Net loss attributable to noncontrolling interests				(11)
Net loss from Neon exited lines attributable to shareholders				$ (39)