Consolidated Statements Of Shareholders' Equity (Unaudited) - USD ($) $ in Millions	Total	Common Stock [Member]	Common shares in treasury [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]	Cumulative Foreign Currency Translation Adjustment [Member]	Postretirement Benefit Liability Adjustment [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance – beginning of period, net of tax at Dec. 31, 2020		$ 11,064	$ (3,644)	$ 9,815	$ 39,337	$ 4,673	$ (1,637)	$ (167)	$ 2,869
Common Shares repurchased			(3,956)
Treasury Stock, Retired, Cost Method, Amount		(79)	590		(511)
Net shares redeemed under employee share-based compensation plans			389	(184)
Exercise of stock options				(45)
Share-based compensation expense				216
Funding of dividends declared to Retained earnings				(1,050)
Net income (loss)	$ 6,398				6,398
Funding of dividends declared from Additional paid-in capital					1,050
Dividends declared on Common Shares					(1,050)
Other Comprehensive Income (Loss), Net of Tax	(1,891)								(1,891)
Balance – end of period, net of tax at Sep. 30, 2021	59,318	10,985	(6,621)	8,752	45,224	2,886	(1,714)	(194)	978
Balance – beginning of period, net of tax at Jun. 30, 2021		11,064	(5,772)	9,046	43,902	3,342	(1,323)	(197)	1,822
Common Shares repurchased			(1,516)
Treasury Stock, Retired, Cost Method, Amount		(79)	590		(511)
Net shares redeemed under employee share-based compensation plans			77	(2)
Exercise of stock options				(15)
Share-based compensation expense				69
Funding of dividends declared to Retained earnings				(346)
Net income (loss)	1,833				1,833
Funding of dividends declared from Additional paid-in capital					346
Dividends declared on Common Shares					(346)
Other Comprehensive Income (Loss), Net of Tax	(844)								(844)
Balance – end of period, net of tax at Sep. 30, 2021	59,318	10,985	(6,621)	8,752	45,224	2,886	(1,714)	(194)	978
Balance – beginning of period, net of tax at Dec. 31, 2021	59,714	10,985	(7,464)	8,478	47,365	2,256	(2,146)	240	350
Common Shares repurchased			(2,815)
Treasury Stock, Retired, Cost Method, Amount		(639)	4,983		(4,344)
Net shares redeemed under employee share-based compensation plans			318	(185)
Exercise of stock options				(35)
Share-based compensation expense				205
Funding of dividends declared to Retained earnings				(1,034)
Net income (loss)	4,001				4,001
Funding of dividends declared from Additional paid-in capital					1,034
Dividends declared on Common Shares					(1,034)
Other Comprehensive Income (Loss), Net of Tax	(12,530)								(12,530)
Balance – end of period, net of tax at Sep. 30, 2022	47,639	10,346	(4,978)	7,429	47,022	(8,611)	(3,781)	261	(12,180)
Balance – beginning of period, net of tax at Jun. 30, 2022		10,666	(6,794)	7,707	48,363	(5,713)	(2,821)	259	(8,275)
Common Shares repurchased			(685)
Treasury Stock, Retired, Cost Method, Amount		(320)	2,473		(2,153)
Net shares redeemed under employee share-based compensation plans			28	10
Exercise of stock options				(8)
Share-based compensation expense				66
Funding of dividends declared to Retained earnings				(346)
Net income (loss)	812				812
Funding of dividends declared from Additional paid-in capital					346
Dividends declared on Common Shares					(346)
Other Comprehensive Income (Loss), Net of Tax	(3,905)								(3,905)
Balance – end of period, net of tax at Sep. 30, 2022	$ 47,639	$ 10,346	$ (4,978)	$ 7,429	$ 47,022	$ (8,611)	$ (3,781)	$ 261	$ (12,180)