Condensed Consolidated Statements of Stockholders' Equity - USD ($) shares in Millions, $ in Millions	Total		Common Stock [Member]	Nonvoting Common Stock [Member]	Preferred Stock [Member]	Common Stock [Member] Common Stock [Member]	Common Stock [Member] Nonvoting Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Stock, at cost [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at beginning of period at Dec. 31, 2021	$ 56,261.0				$ 9,954.0	$ 20.0	$ 1.0	$ 26,741.0	$ 25,992.0	$ (5,338.0)	$ (1,109.0)
Beginning balance (in shares) at Dec. 31, 2021						1,995	79
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	3,195.0	[1]	$ 3,062.0	$ 133.0					3,195.0
Other comprehensive income (loss), net of tax	(14,913.0)										(14,913.0)
Issuance of preferred stock, net	740.0				740.0
Dividends declared on preferred stock	(250.5)								(251.0)
Dividends declared on common stock	(762.0)								(762.0)
Stock option exercises and other	33.0							(56.0)		89.0
Share-based compensation	165.0							165.0
Other	45.0							68.0		(23.0)
Ending balance (in shares) at Jun. 30, 2022						1,995	79
Balance at end of period at Jun. 30, 2022	44,513.0				10,694.0	$ 20.0	$ 1.0	26,918.0	28,174.0	(5,272.0)	(16,022.0)
Balance at beginning of period at Mar. 31, 2022	48,098.0				10,694.0	$ 20.0	$ 1.0	26,826.0	26,895.0	(5,293.0)	(11,045.0)
Beginning balance (in shares) at Mar. 31, 2022						1,995	79
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,793.0		1,718.0	75.0					1,793.0
Other comprehensive income (loss), net of tax	(4,977.0)										(4,977.0)
Dividends declared on preferred stock	(132.6)								(133.0)
Dividends declared on common stock	(381.0)								(381.0)
Stock option exercises and other	3.0							(5.0)		8.0
Share-based compensation	53.0							53.0
Other	57.0							44.0		13.0
Ending balance (in shares) at Jun. 30, 2022						1,995	79
Balance at end of period at Jun. 30, 2022	44,513.0				10,694.0	$ 20.0	$ 1.0	26,918.0	28,174.0	(5,272.0)	(16,022.0)
Balance at beginning of period at Dec. 31, 2022	36,608.0	[2]			9,706.0	$ 20.0	$ 1.0	27,075.0	31,066.0	(8,639.0)	(22,621.0)
Beginning balance (in shares) at Dec. 31, 2022						2,023	51
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,897.0	[1]	2,817.0	80.0					2,897.0
Other comprehensive income (loss), net of tax	1,891.0										1,891.0
Redemption and repurchase of preferred stock, inclusive of tax	(471.0)				(515.0)				44.0
Dividends declared on preferred stock	(220.9)								(221.0)
Dividends declared on common stock	(921.0)								(921.0)
Repurchase of common stock, inclusive of tax	(2,869.0)									(2,869.0)
Stock option exercises and other	24.0							(101.0)		125.0
Share-based compensation	182.0							182.0
Other	27.0							64.0		(37.0)
Ending balance (in shares) at Jun. 30, 2023						2,023	51
Balance at end of period at Jun. 30, 2023	37,147.0	[2]			9,191.0	$ 20.0	$ 1.0	27,220.0	32,865.0	(11,420.0)	(20,730.0)
Balance at beginning of period at Mar. 31, 2023	36,347.0				9,191.0	$ 20.0	$ 1.0	27,136.0	32,144.0	(11,455.0)	(20,690.0)
Beginning balance (in shares) at Mar. 31, 2023						2,023	51
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,294.0		$ 1,258.0	$ 36.0					1,294.0
Other comprehensive income (loss), net of tax	(40.0)										(40.0)
Dividends declared on preferred stock	(115.5)								(116.0)
Dividends declared on common stock	(457.0)								(457.0)
Stock option exercises and other	5.0							(9.0)		14.0
Share-based compensation	53.0							53.0
Other	61.0							40.0		21.0
Ending balance (in shares) at Jun. 30, 2023						2,023	51
Balance at end of period at Jun. 30, 2023	$ 37,147.0	[2]			$ 9,191.0	$ 20.0	$ 1.0	$ 27,220.0	$ 32,865.0	$ (11,420.0)	$ (20,730.0)

[1] Certain prior period amounts have been reclassified to conform to the current year presentation. See Note 1 for additional information.

[2] Certain prior year amounts have been reclassified to conform to the current year presentation. See Note 1 for additional information.