Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Changes in accumulated other comprehensive income (loss), net of income taxes
Beginning of the period	$ 36,686
Other comprehensive income (loss)	12	$ (100)
End of the period	37,010
Cumulative Foreign Currency Translation (Loss) Adjustments
Changes in accumulated other comprehensive income (loss), net of income taxes
Beginning of the period	(6,733)	(5,839)
Other comprehensive income (loss) before reclassifications	139	(106)
Amounts reclassified from accumulated other comprehensive income	0	0
Other comprehensive income (loss)	139	(106)
End of the period	(6,594)	(5,945)
Net Actuarial (Losses) and Prior Service (Costs) and Credits
Changes in accumulated other comprehensive income (loss), net of income taxes
Beginning of the period	(1,493)	(2,670)
Other comprehensive income (loss) before reclassifications	2	17
Amounts reclassified from accumulated other comprehensive income	0	45
Other comprehensive income (loss)	2	62
End of the period	(1,491)	(2,608)
Cumulative Gains (Losses) on Derivative Instruments Designated as Cash Flow Hedges and Other
Changes in accumulated other comprehensive income (loss), net of income taxes
Beginning of the period	175	135
Other comprehensive income (loss) before reclassifications	(42)	(34)
Amounts reclassified from accumulated other comprehensive income	(87)	(22)
Other comprehensive income (loss)	(129)	(56)
End of the period	$ 46	$ 79