Fair Value Measurements - Narrative (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020 USD ($) contract	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) contract	Jun. 30, 2019 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jun. 30, 2017 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
(Losses) and gains on derivative financial instruments recognized in other non-operating items (less than)	$ 1	$ 1	$ 2	$ 1
Other long-term investments	$ 9		$ 9		$ 9	$ 9
Foreign exchange swaps | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Maturity period of swap contracts			6 months
Foreign exchange swaps | Maturity Beyond Six Months
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of foreign currency derivatives held | contract	0		0
Foreign exchange forward contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notional value	$ 177		$ 177			291
Derivative asset	1		1			1
Fair Value Measured at Net Asset Value Per Share
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment	$ 12		12			$ 10	$ 15
Distributions from fund			$ 3