Consolidated Statements of Shareholders’ Equity - USD ($) $ in Millions	Total	Preferred stock par value	Preferred stock additional capital paid-in	Common stock par value	Common stock additional capital paid-in	Retained income	Retained income Cumulative effect of change in accounting principle	Deferred Employee Stock Ownership Plan (“ESOP”) expense	Treasury stock	Accumulated other comprehensive income (loss)	Accumulated other comprehensive income (loss) Cumulative effect of change in accounting principle
Balance, beginning of year at Dec. 31, 2017			$ 1,746		$ 3,313	$ 41,579	$ 1,088	$ (3)	$ (25,982)	$ 1,889	$ (910)
Increase (decrease) in equity [Roll forward]
Preferred stock issuance, net of issuance costs			557
Preferred stock redemption			(373)
Forward contract on accelerated share repurchase agreement					(105)
Equity incentive plans activity					102
Net income	$ 2,160					2,160
Dividends on common stock (declared per share of $2.16, $2.00 and $1.84)						(646)
Dividends on preferred stock						(148)
Payments	0
Shares acquired									(2,198)
Shares reissued under equity incentive plans, net									95
Change in unrealized net capital gains and losses	(754)									(754)
Change in unrealized foreign currency translation adjustments	(48)									(48)
Change in unamortized pension and other postretirement prior service credit	(59)									(59)
Balance, end of year at Dec. 31, 2018	21,312	$ 0	1,930	$ 9	3,310	44,033	21	(3)	(28,085)	118	0
Increase (decrease) in equity [Roll forward]
Preferred stock issuance, net of issuance costs			1,414
Preferred stock redemption			(1,096)
Forward contract on accelerated share repurchase agreement					75
Equity incentive plans activity					78
Net income	4,847					4,847
Dividends on common stock (declared per share of $2.16, $2.00 and $1.84)						(658)
Dividends on preferred stock						(169)
Payments	3
Shares acquired									(1,810)
Shares reissued under equity incentive plans, net									149
Change in unrealized net capital gains and losses	1,889									1,889
Change in unrealized foreign currency translation adjustments	(10)									(10)
Change in unamortized pension and other postretirement prior service credit	(47)									(47)
Balance, end of year at Dec. 31, 2019	25,998	0	2,248	9	3,463	48,074	$ (88)	0	(29,746)	1,950	$ 0
Increase (decrease) in equity [Roll forward]
Preferred stock issuance, net of issuance costs			0
Preferred stock redemption			(278)
Forward contract on accelerated share repurchase agreement					(38)
Equity incentive plans activity					73
Net income	5,576					5,576
Dividends on common stock (declared per share of $2.16, $2.00 and $1.84)						(680)
Dividends on preferred stock						(115)
Payments	0
Shares acquired									(1,700)
Shares reissued under equity incentive plans, net									115
Change in unrealized net capital gains and losses	1,293									1,293
Change in unrealized foreign currency translation adjustments	52									52
Change in unamortized pension and other postretirement prior service credit	9									9
Balance, end of year at Dec. 31, 2020	$ 30,217	$ 0	$ 1,970	$ 9	$ 3,498	$ 52,767		$ 0	$ (31,331)	$ 3,304