Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Changes in accumulated other comprehensive income (loss), net of income taxes
Beginning of the period	$ 32,784
Other Comprehensive Income (Loss)	572	$ (481)	$ (879)
End of the period	35,802	32,784
Cumulative Foreign Currency Translation Adjustments
Changes in accumulated other comprehensive income (loss), net of income taxes
Beginning of the period	(4,859)	(4,924)
Other comprehensive income (loss) before reclassifications	(980)	65
Other Comprehensive Income (Loss)	(980)	65
End of the period	(5,839)	(4,859)	(4,924)
Net Actuarial (Losses) and Prior Service (Costs) and Credits
Changes in accumulated other comprehensive income (loss), net of income taxes
Beginning of the period	(3,871)	(3,540)
Other comprehensive income (loss) before reclassifications	954	(523)
(Income) loss amounts reclassified from accumulated other comprehensive income	247	192
Other Comprehensive Income (Loss)	1,201	(331)
End of the period	(2,670)	(3,871)	(3,540)
Cumulative Gains (Losses) on Derivative Instruments Designated as Cash Flow Hedges
Changes in accumulated other comprehensive income (loss), net of income taxes
Beginning of the period	(216)	(1)
Other comprehensive income (loss) before reclassifications	137	(140)
(Income) loss amounts reclassified from accumulated other comprehensive income	214	(75)
Other Comprehensive Income (Loss)	351	(215)
End of the period	135	(216)	(1)
Accumulated Other Comprehensive Income (Loss):
Changes in accumulated other comprehensive income (loss), net of income taxes
Beginning of the period	(8,946)	(8,465)
Other comprehensive income (loss) before reclassifications	111	(598)
(Income) loss amounts reclassified from accumulated other comprehensive income	461	117
Other Comprehensive Income (Loss)	572	(481)	(879)
End of the period	$ (8,374)	$ (8,946)	$ (8,465)