Financial Instruments - Cash Flow Hedges Effect on Accumulated Other Comprehensive Earnings/(Losses), Net of Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net [Abstract]
Balance at beginning of period	$ 27,654	$ 27,317	$ 25,602
Transfer of realized (gains)/losses in fair value to earnings	(44)	285	279
Balance at end of period	28,323	27,654	27,317
Cash Flow Hedges
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net [Abstract]
Unrealized gain/(loss) in fair value	168	(109)	(199)
Derivative Cash Flow Hedges
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net [Abstract]
Balance at beginning of period	(161)	(213)	(168)
Balance at end of period	(148)	(161)	(213)
Derivative Cash Flow Hedges | Cash Flow Hedges
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net [Abstract]
Balance at beginning of period	(161)	(213)	(168)
Transfer of realized (gains)/losses in fair value to earnings	(155)	161	154
Unrealized gain/(loss) in fair value	168	(109)	(199)
Balance at end of period	$ (148)	$ (161)	$ (213)