Condensed Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Millions	Total	Preferred Stock [Member]	Common Stock	Additional Paid-in Capital	Retained Earnings	AOCI Attributable to Parent [Member]	Treasury Stock, Common	Share-based Payment Arrangement [Member] Treasury Stock, Common
Beginning balance at Dec. 31, 2021	$ 17,805			$ 3,309	$ 15,770	$ 128	$ (1,740)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of shares under incentive and stock compensation plans and other				(122)
Stock-based compensation plans expense				77
Net income	887				887
Dividends declared on preferred stock	(10)				(10)
Dividends declared on common stock					(253)
Treasury stock acquired	(850)						(850)
Issuance of shares under incentive and stock compensation plans from treasury stock and other								$ 142
Net shares acquired related to employee incentive and stock compensation plans							(54)
Total other comprehensive income (loss)						(3,377)
Ending balance at Jun. 30, 2022	$ 14,245	$ 334	$ 4	3,264	16,394	(3,249)	(2,502)
Preferred Stock, Shares Outstanding, Ending Balance at Jun. 30, 2022		13,800
Common Shares Outstanding, beginning of period at Dec. 31, 2021			334,926
Shares Granted or Issued, Share-based Payment Arrangement [Abstract]
Treasury stock acquired	(12,000)		(12,037)
Issuance of shares under incentive and stock compensation plans and other			2,621
Return of shares under incentive and stock compensation plans to treasury stock			(765)
Common Shares Outstanding, at end of period at Jun. 30, 2022			324,745
Shares Granted or Issued, Share-based Payment Arrangement [Abstract]
Cash dividends declared per common share	$ 0.770
Cash dividends declared per preferred share	$ 750.00
Beginning balance at Mar. 31, 2022				3,249	16,081	(1,710)	(2,068)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of shares under incentive and stock compensation plans and other				(7)
Stock-based compensation plans expense				22
Net income	$ 444				444
Dividends declared on preferred stock	(5)				(5)
Dividends declared on common stock					(126)
Treasury stock acquired							(450)
Issuance of shares under incentive and stock compensation plans from treasury stock and other								18
Net shares acquired related to employee incentive and stock compensation plans							(2)
Total other comprehensive income (loss)						(1,539)
Ending balance at Jun. 30, 2022	$ 14,245	$ 334	$ 4	3,264	16,394	(3,249)	(2,502)
Preferred Stock, Shares Outstanding, Ending Balance at Jun. 30, 2022		13,800
Common Shares Outstanding, beginning of period at Mar. 31, 2022			330,709
Shares Granted or Issued, Share-based Payment Arrangement [Abstract]
Treasury stock acquired			(6,355)
Issuance of shares under incentive and stock compensation plans and other			411
Return of shares under incentive and stock compensation plans to treasury stock			(20)
Common Shares Outstanding, at end of period at Jun. 30, 2022			324,745
Shares Granted or Issued, Share-based Payment Arrangement [Abstract]
Cash dividends declared per common share	$ 0.385
Cash dividends declared per preferred share	$ 375.00
Beginning balance at Dec. 31, 2022	$ 13,676			1,895	17,058	(3,841)	(1,773)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of shares under incentive and stock compensation plans and other				(119)
Stock-based compensation plans expense				88
Net income	1,082				1,082
Dividends declared on preferred stock	(10)				(10)
Dividends declared on common stock					(265)
Treasury stock acquired	(700)						(707)
Issuance of shares under incentive and stock compensation plans from treasury stock and other								139
Net shares acquired related to employee incentive and stock compensation plans							(49)
Total other comprehensive income (loss)						317
Ending balance at Jun. 30, 2023	$ 14,152	$ 334	$ 3	1,864	17,865	(3,524)	(2,390)
Preferred Stock, Shares Outstanding, Ending Balance at Jun. 30, 2023		13,800
Common Shares Outstanding, beginning of period at Dec. 31, 2022			315,111
Shares Granted or Issued, Share-based Payment Arrangement [Abstract]
Treasury stock acquired	(9,700)		(9,727)
Issuance of shares under incentive and stock compensation plans and other			2,312
Return of shares under incentive and stock compensation plans to treasury stock			(625)
Common Shares Outstanding, at end of period at Jun. 30, 2023			307,071
Shares Granted or Issued, Share-based Payment Arrangement [Abstract]
Cash dividends declared per common share	$ 0.850
Cash dividends declared per preferred share	$ 750.00
Beginning balance at Mar. 31, 2023				1,847	17,454	(3,254)	(2,044)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of shares under incentive and stock compensation plans and other				(5)
Stock-based compensation plans expense				22
Net income	$ 547				547
Dividends declared on preferred stock	(5)				(5)
Dividends declared on common stock					(131)
Treasury stock acquired							(353)
Issuance of shares under incentive and stock compensation plans from treasury stock and other								$ 7
Net shares acquired related to employee incentive and stock compensation plans							0
Total other comprehensive income (loss)						(270)
Ending balance at Jun. 30, 2023	$ 14,152	$ 334	$ 3	$ 1,864	$ 17,865	$ (3,524)	$ (2,390)
Preferred Stock, Shares Outstanding, Ending Balance at Jun. 30, 2023		13,800
Common Shares Outstanding, beginning of period at Mar. 31, 2023			311,780
Shares Granted or Issued, Share-based Payment Arrangement [Abstract]
Treasury stock acquired			(5,008)
Issuance of shares under incentive and stock compensation plans and other			307
Return of shares under incentive and stock compensation plans to treasury stock			(8)
Common Shares Outstanding, at end of period at Jun. 30, 2023			307,071
Shares Granted or Issued, Share-based Payment Arrangement [Abstract]
Cash dividends declared per common share	$ 0.425
Cash dividends declared per preferred share	$ 375.00