Consolidated Statements of Changes in Shareholders' Equity (Unaudited) - USD ($) $ in Millions	Total	Preferred Stock [Member]	Common Stock [Member]	Share-Based Awards [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Retained Earnings [Member] Cumulative Effect, Period of Adoption, Adjusted Balance [Member]	Retained Earnings [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Stock Held in Treasury, at Cost [Member]
Beginning balance at Dec. 31, 2018		$ 11,203	$ 9	$ 2,845	$ 54,005	$ 100,100			$ 693	$ (78,670)
Beginning balance (Accounting Standards Update 2016-02 [Member]) at Dec. 31, 2018							$ 100,112	$ 12
Beginning balance (Accounting Standards Update 2016-13 [Member]) at Dec. 31, 2018								0
Issued		500	0
Redeemed		(500)
Issuance and amortization of share-based awards				1,888
Delivery of common stock underlying share-based awards				(1,617)	1,610
Forfeiture of share-based awards				(64)
Cancellation of share-based awards in satisfaction of withholding tax requirements					(739)
Preferred stock issuance costs, net of reversals upon redemption					3
Other comprehensive income/(loss)	$ (1,177)								(1,177)
Repurchased										(3,173)
Reissued										12
Other										(10)
Net earnings	6,549					6,549
Dividends and dividend equivalents declared on common stock and share-based awards						(1,091)
Dividends declared on preferred stock	(369)					(369)
Preferred stock redemption premium						(7)
Ending balance at Sep. 30, 2019	92,012	11,203	9	3,052	54,879	105,194			(484)	(81,841)
Beginning balance at Dec. 31, 2018		11,203	9	2,845	54,005	100,100			693	(78,670)
Beginning balance (Accounting Standards Update 2016-02 [Member]) at Dec. 31, 2018							100,112	12
Beginning balance (Accounting Standards Update 2016-13 [Member]) at Dec. 31, 2018								0
Ending balance at Dec. 31, 2019	90,265	11,203	9	3,195	54,883	106,465			(1,484)	(84,006)
Ending balance (Accounting Standards Update 2016-02 [Member]) at Dec. 31, 2019							105,827	0
Ending balance (Accounting Standards Update 2016-13 [Member]) at Dec. 31, 2019								(638)
Beginning balance at Jun. 30, 2019		11,203	9	2,930	54,865	103,867			(815)	(81,167)
Beginning balance (Accounting Standards Update 2016-02 [Member]) at Jun. 30, 2019							103,867	0
Beginning balance (Accounting Standards Update 2016-13 [Member]) at Jun. 30, 2019								0
Issued		0	0
Redeemed		0
Issuance and amortization of share-based awards				181
Delivery of common stock underlying share-based awards				(20)	22
Forfeiture of share-based awards				(39)
Cancellation of share-based awards in satisfaction of withholding tax requirements					(8)
Preferred stock issuance costs, net of reversals upon redemption					0
Other comprehensive income/(loss)	331								331
Repurchased										(673)
Reissued										1
Other										(2)
Net earnings	1,877					1,877
Dividends and dividend equivalents declared on common stock and share-based awards						(466)
Dividends declared on preferred stock	(84)					(84)
Preferred stock redemption premium						0
Ending balance at Sep. 30, 2019	92,012	11,203	9	3,052	54,879	105,194			(484)	(81,841)
Beginning balance at Dec. 31, 2019	90,265	11,203	9	3,195	54,883	106,465			(1,484)	(84,006)
Beginning balance (Accounting Standards Update 2016-02 [Member]) at Dec. 31, 2019							105,827	0
Beginning balance (Accounting Standards Update 2016-13 [Member]) at Dec. 31, 2019								(638)
Issued		350	0
Redeemed		(350)
Issuance and amortization of share-based awards				1,770
Delivery of common stock underlying share-based awards				(1,597)	1,607
Forfeiture of share-based awards				(60)
Cancellation of share-based awards in satisfaction of withholding tax requirements					(828)
Preferred stock issuance costs, net of reversals upon redemption					0
Other comprehensive income/(loss)	849								849
Repurchased	(1,928)									(1,928)
Reissued										11
Other										(7)
Net earnings	4,953					4,953
Dividends and dividend equivalents declared on common stock and share-based awards						(1,347)
Dividends declared on preferred stock	(399)					(399)
Preferred stock redemption premium						(1)
Ending balance at Sep. 30, 2020	92,650	11,203	9	3,308	55,662	109,033			(635)	(85,930)
Beginning balance at Jun. 30, 2020		11,203	9	3,203	55,637	106,248			(341)	(85,930)
Beginning balance (Accounting Standards Update 2016-02 [Member]) at Jun. 30, 2020							$ 106,248	0
Beginning balance (Accounting Standards Update 2016-13 [Member]) at Jun. 30, 2020								$ 0
Issued		0	0
Redeemed		0
Issuance and amortization of share-based awards				176
Delivery of common stock underlying share-based awards				(33)	34
Forfeiture of share-based awards				(38)
Cancellation of share-based awards in satisfaction of withholding tax requirements					(9)
Preferred stock issuance costs, net of reversals upon redemption					0
Other comprehensive income/(loss)	(294)								(294)
Repurchased	0									0
Reissued										1
Other										(1)
Net earnings	3,367					3,367
Dividends and dividend equivalents declared on common stock and share-based awards						(448)
Dividends declared on preferred stock	(134)					(134)
Preferred stock redemption premium						0
Ending balance at Sep. 30, 2020	$ 92,650	$ 11,203	$ 9	$ 3,308	$ 55,662	$ 109,033			$ (635)	$ (85,930)