Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 1,801	$ 2,276	$ 3,468	$ 3,799
Other comprehensive income (loss), net of tax:
Change in net unrealized losses/gains on investments	175	730	(187)	41
Change in non-credit component of impairment losses on investments	1	10	2	(22)
Change in net unrealized gains/losses on cash flow hedges	2	3	6	6
Change in net periodic pension and postretirement costs	8	10	18	17
Foreign currency translation adjustments	(6)	1	(6)	0
Other comprehensive income (loss)	180	754	(167)	42
Net income attributable to noncontrolling interests	(8)	0	(10)	0
Other comprehensive income attributable to noncontrolling interests	(2)	0	0	0
Total shareholders’ comprehensive income	$ 1,971	$ 3,030	$ 3,291	$ 3,841