Consolidated Statement of Comprehensive Income (Loss) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income (loss) from continuing and discontinued operations	$ 4,112	$ (3,295)	$ 5,948
Pension and postretirement benefit plans adjustments
Net actuarial gain (loss) arising during period	3,246	(202)	(543)
Prior service credit (cost) arising during period	(59)	2,095	(6)
Amortization of actuarial loss and prior service cost	258	373	228
Other	23	(51)	(93)
Pension and postretirement benefit plans adjustments	3,468	2,215	(414)
Change in unrealized cash flow hedging	(254)	263	18
Foreign currency translation adjustments	(647)	609	268
Other comprehensive income (loss), before tax	2,567	3,087	(128)
Income tax (expense) benefit related to items of other comprehensive income (loss)	(748)	(547)	43
Other comprehensive income (loss), net of tax	1,819	2,540	(85)
Comprehensive income (loss)	5,931	(755)	5,863
Less: comprehensive income attributable to noncontrolling interest	248	224	399
Comprehensive income (loss) attributable to common shareowners	$ 5,683	$ (979)	$ 5,464