Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net earnings, including noncontrolling interests	$ 721	$ 869	$ 517
Net unrealized gains (losses) on securities:
Unrealized holding gains (losses) on securities arising during the period	700	788	(544)
Reclassification adjustment for realized (gains) losses included in net earnings	(307)	(9)	8
Total net unrealized gains (losses) on securities	393	779	(536)
Net unrealized gains on cash flow hedges	24	28	2
Foreign currency translation adjustments	(1)	7	(10)
Pension and other postretirement plans adjustments	0	1	0
Other comprehensive income (loss), net of tax	416	815	(544)
Total comprehensive income (loss), net of tax	1,137	1,684	(27)
Less: Comprehensive income (loss) attributable to noncontrolling interests	(9)	(28)	(13)
Comprehensive income (loss) attributable to shareholders	$ 1,146	$ 1,712	$ (14)