Equity Activity - Reclassifications and Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Unrealized gains (losses) on cash flow hedges	$ 0	$ 0	$ 0	$ 0
Gains (losses) on available-for-sale-debt securities
Other comprehensive income/(loss), Before Tax Amount	37	17	(118)	20
Other comprehensive income/(loss), Tax (Expense)/Benefit	14	2	(3)	5
Other comprehensive income/(loss), net of tax	52	19	(121)	25
Accumulated Other Comprehensive Income/(Loss)
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Other comprehensive income before reclassification			(123)	24
Reclassification/amortization, Net of Tax Amount			1	1
Other comprehensive income/(loss), Before Tax Amount	37	17	(118)	20
Other comprehensive income/(loss), Tax (Expense)/Benefit	14	2	(3)	5
Other comprehensive income/(loss), net of tax	52	19	(121)	25
Foreign Currency Translation Adjustments
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Other comprehensive income before reclassification			(123)	25
Other comprehensive income/(loss), Before Tax Amount	36	16	(120)	20
Other comprehensive income/(loss), Tax (Expense)/Benefit	14	2	(3)	5
Other comprehensive income/(loss), net of tax	51	19	(123)	25
Net Change Retirement-Related Benefit Plans
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Other comprehensive income before reclassification			0	0
Reclassification/amortization, Net of Tax Amount			1	1
Other comprehensive income/(loss), Before Tax Amount	1	0	2	0
Other comprehensive income/(loss), Tax (Expense)/Benefit	0	0	0	0
Other comprehensive income/(loss), net of tax	1	0	2	0
Retirement-Related Benefit Plans, Curtailments and Settlements
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Other comprehensive income/(loss), arising during the period, Before Tax Amount	0		0
Other comprehensive income/(loss), arising during the period, Tax (Expense)/Benefit	0		0
Other comprehensive income before reclassification	0		0
Retirement-Related Benefit Plans, Prior Service Costs/(Credits)
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Reclassification/amortization, Before Tax Amount	0	0	0	0
Reclassification/amortization, Tax (Expense)/Benefit	0	0	0	0
Reclassification/amortization, Net of Tax Amount	0	0	0	0
Retirement-Related Benefit Plans, Net Gains/(Losses)
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Other comprehensive income/(loss), arising during the period, Before Tax Amount			0	0
Other comprehensive income/(loss), arising during the period, Tax (Expense)/Benefit		0	0	0
Other comprehensive income before reclassification		0	0	0
Reclassification/amortization, Before Tax Amount	1	0	2	1
Reclassification/amortization, Tax (Expense)/Benefit	0	0	0	0
Reclassification/amortization, Net of Tax Amount	$ 1	$ 0	$ 2	$ 1