Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 22,984	$ 23,071	$ 22,290
Net change in accumulated other comprehensive income (loss)	(50)	(158)	(140)
Ending Balance	22,177	22,984	23,071
Tax impact for the changes in each component of accumulated other comprehensive (loss) income
Total tax impact	90	(81)	(45)
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(2,895)	(2,737)	(2,597)
Ending Balance	(2,945)	(2,895)	(2,737)
Net Unrealized Gains (Losses) on Debt Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	65	33	(8)
Net change in accumulated other comprehensive income (loss)	(42)	32	41
Ending Balance	23	65	33
Tax impact for the changes in each component of accumulated other comprehensive (loss) income
Total tax impact	(13)	9	12
Foreign Currency Translation Adjustment Gains (Losses)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(2,229)	(2,189)	(2,133)
Net change in accumulated other comprehensive income (loss)	(163)	(40)	(56)
Ending Balance	(2,392)	(2,229)	(2,189)
Net Unrealized Pension and Other Postretirement Benefit Gains (Losses)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(731)	(581)	(456)
Net change in accumulated other comprehensive income (loss)	155	(150)	(125)
Ending Balance	(576)	(731)	(581)
Tax impact for the changes in each component of accumulated other comprehensive (loss) income
Total tax impact	52	(28)	(38)
Net translation on investments in foreign operations
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Net change in accumulated other comprehensive income (loss)	(339)	213	84
Tax impact for the changes in each component of accumulated other comprehensive (loss) income
Total tax impact	(1)	17	24
Net hedges of investments in foreign operations
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Net change in accumulated other comprehensive income (loss)	176	(253)	(140)
Tax impact for the changes in each component of accumulated other comprehensive (loss) income
Total tax impact	$ 52	$ (79)	$ (43)