Condensed Consolidated Statements of Shareholders’ Equity (unaudited) - USD ($) $ in Millions	Total	Preferred Stock	Preferred stock additional capital paid-in	Common stock par value	Common stock additional capital paid-in	Retained income	Deferred ESOP expense	Treasury stock	Accumulated other comprehensive income	Previously reported	Previously reported Retained income	Previously reported Accumulated other comprehensive income	Impact of change	Impact of change Retained income	Impact of change Accumulated other comprehensive income
Balance, beginning of period at Dec. 31, 2017			$ 1,746		$ 3,313	$ 41,579		$ (25,982)	$ 1,889		$ 43,162	$ 306
Balance, beginning of period (Impact of change) at Dec. 31, 2017														$ (1,583)	$ 1,583
Increase (decrease) in equity
Preferred stock issuance			557
Forward contract on accelerated share repurchase agreement					45
Activity under equity incentive plans					33
Net income	$ 1,723					1,723				$ 1,651	1,651
Net income | Impact of change													$ 72	72
Dividends on common stock (declared per share of $0.50, $0.46, $1.00 and $0.92)						(325)					(325)
Dividends on common stock (declared per share of $0.50, $0.46, $1.00 and $0.92) | Impact of change														0
Dividends on preferred stock						(68)					(68)
Dividends on preferred stock | Impact of change														0
Shares acquired								(892)
Shares reissued under equity incentive plans, net								56
Change in unrealized net capital gains and losses	(698)								(698)	(698)		(698)
Change in unrealized net capital gains and losses | Impact of change													0		0
Change in unrealized foreign currency translation adjustments	(8)								(8)	(11)		(11)
Change in unrealized foreign currency translation adjustments | Impact of change													3		3
Change in unamortized pension and other postretirement prior service credit	(30)								(30)	45		45
Change in unamortized pension and other postretirement prior service credit | Impact of change													(75)		(75)
Balance, end of period at Jun. 30, 2018	$ 23,122	$ 0	2,303	$ 9	3,391	43,997	$ (3)	(26,818)	243	23,122	45,508	(1,268)
Balance, end of period (Impact of change) at Jun. 30, 2018													0	(1,511)	1,511
Increase (decrease) in equity
Dividends (in USD per share)	$ 0.92
Balance, beginning of period at Mar. 31, 2018			2,303		3,367	43,479		(26,280)	398		45,031	(1,150)
Balance, beginning of period (Impact of change) at Mar. 31, 2018														(1,552)	1,548
Increase (decrease) in equity
Preferred stock issuance			0
Forward contract on accelerated share repurchase agreement					0
Activity under equity incentive plans					24
Net income	$ 717					717				676	676
Net income | Impact of change													41	41
Dividends on common stock (declared per share of $0.50, $0.46, $1.00 and $0.92)						(160)					(160)
Dividends on common stock (declared per share of $0.50, $0.46, $1.00 and $0.92) | Impact of change														0
Dividends on preferred stock						(39)					(39)
Dividends on preferred stock | Impact of change														0
Shares acquired								(559)
Shares reissued under equity incentive plans, net								21
Change in unrealized net capital gains and losses	(133)								(133)	(133)		(133)
Change in unrealized net capital gains and losses | Impact of change													0		0
Change in unrealized foreign currency translation adjustments	(6)								(6)	(7)		(7)
Change in unrealized foreign currency translation adjustments | Impact of change													1		1
Change in unamortized pension and other postretirement prior service credit	(16)								(16)	22		22
Change in unamortized pension and other postretirement prior service credit | Impact of change													(38)		(38)
Balance, end of period at Jun. 30, 2018	$ 23,122	0	2,303	9	3,391	43,997	(3)	(26,818)	243	23,122	45,508	(1,268)
Balance, end of period (Impact of change) at Jun. 30, 2018													0	(1,511)	1,511
Increase (decrease) in equity
Dividends (in USD per share)	$ 0.46
Balance, beginning of period at Dec. 31, 2018	$ 21,312		1,930		3,310	44,033		(28,085)	118		45,708	(1,557)
Balance, beginning of period (Impact of change) at Dec. 31, 2018														(1,675)	1,675
Increase (decrease) in equity
Preferred stock issuance			0
Forward contract on accelerated share repurchase agreement					150
Activity under equity incentive plans					17
Net income	2,143					2,143				2,207	2,207
Net income | Impact of change													(64)	(64)
Dividends on common stock (declared per share of $0.50, $0.46, $1.00 and $0.92)						(333)					(333)
Dividends on common stock (declared per share of $0.50, $0.46, $1.00 and $0.92) | Impact of change														0
Dividends on preferred stock						(61)					(61)
Dividends on preferred stock | Impact of change														0
Shares acquired								(498)
Shares reissued under equity incentive plans, net								83
Change in unrealized net capital gains and losses	1,656								1,656	1,656		1,656
Change in unrealized net capital gains and losses | Impact of change													0		0
Change in unrealized foreign currency translation adjustments	9								9	14		14
Change in unrealized foreign currency translation adjustments | Impact of change													(5)		(5)
Change in unamortized pension and other postretirement prior service credit	(23)								(23)	135		135
Change in unamortized pension and other postretirement prior service credit | Impact of change													(158)		(158)
Balance, end of period at Jun. 30, 2019	$ 24,476	0	1,930	9	3,477	45,803	(3)	(28,500)	1,760	24,703	47,542	248
Balance, end of period (Impact of change) at Jun. 30, 2019													(227)	(1,739)	1,512
Increase (decrease) in equity
Dividends (in USD per share)	$ 1.00
Balance, beginning of period at Mar. 31, 2019			1,930		3,291	45,148		(28,042)	1,085		46,818	(566)
Balance, beginning of period (Impact of change) at Mar. 31, 2019														(1,670)	1,651
Increase (decrease) in equity
Preferred stock issuance			0
Forward contract on accelerated share repurchase agreement					150
Activity under equity incentive plans					36
Net income	$ 851					851				920	920
Net income | Impact of change													(69)	(69)
Dividends on common stock (declared per share of $0.50, $0.46, $1.00 and $0.92)						(166)					(166)
Dividends on common stock (declared per share of $0.50, $0.46, $1.00 and $0.92) | Impact of change														0
Dividends on preferred stock						(30)					(30)
Dividends on preferred stock | Impact of change														0
Shares acquired								(498)
Shares reissued under equity incentive plans, net								40
Change in unrealized net capital gains and losses	682								682	682		682
Change in unrealized net capital gains and losses | Impact of change													0		0
Change in unrealized foreign currency translation adjustments	4								4	7		7
Change in unrealized foreign currency translation adjustments | Impact of change													(3)		(3)
Change in unamortized pension and other postretirement prior service credit	(11)								(11)	125		125
Change in unamortized pension and other postretirement prior service credit | Impact of change													(136)		(136)
Balance, end of period at Jun. 30, 2019	$ 24,476	$ 0	$ 1,930	$ 9	$ 3,477	$ 45,803	$ (3)	$ (28,500)	$ 1,760	$ 24,703	$ 47,542	$ 248
Balance, end of period (Impact of change) at Jun. 30, 2019													$ (227)	$ (1,739)	$ 1,512
Increase (decrease) in equity
Dividends (in USD per share)	$ 0.50