Equity Activity - Reclassifications and Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Reclassifications and Taxes Related to Items of Other Comprehensive Income (Loss)
Other comprehensive income (loss)	$ (114)	$ 128	$ (178)	$ 18
Accumulated Other Comprehensive Income (Loss)
Reclassifications and Taxes Related to Items of Other Comprehensive Income (Loss)
Other comprehensive income (loss), before tax amount	(110)	131	(168)	26
Other comprehensive income (loss), tax (expense) benefit	(3)	(2)	(10)	(8)
Other comprehensive income (loss)	(114)	128	(178)	18
Foreign Currency Translation Adjustments
Reclassifications and Taxes Related to Items of Other Comprehensive Income (Loss)
Other comprehensive income (loss), before tax amount	(125)	121	(203)	(1)
Other comprehensive income (loss)	(125)	121	(203)	(1)
Unrealized Gains (Losses) on Cash Flow Hedges
Reclassifications and Taxes Related to Items of Other Comprehensive Income (Loss)
Unrealized gains (losses) arising during the period, before tax amount	3		3
Unrealized gains (losses) arising during the period, net of tax amount	3		3
Other comprehensive income (loss), before tax amount	3		3
Other comprehensive income (loss)	3		3
Net Change Retirement-Related Benefit Plans
Reclassifications and Taxes Related to Items of Other Comprehensive Income (Loss)
Other comprehensive income (loss), before tax amount	12	9	32	27
Other comprehensive income (loss), tax (expense) benefit	(3)	(2)	(10)	(8)
Other comprehensive income (loss)	8	7	22	19
Retirement-Related Benefit Plans, Net Gains (Losses)
Reclassifications and Taxes Related to Items of Other Comprehensive Income (Loss)
Unrealized gains (losses) arising during the period, tax (expense) benefit		1
Unrealized gains (losses) arising during the period, net of tax amount		1		1
Reclassification/amortization, before tax amount	12	9	32	27
Reclassification/amortization, tax (expense) benefit	(3)	(3)	(10)	(9)
Reclassification/amortization, net of tax amount	$ 8	$ 6	$ 22	$ 18