Revenue from Contract with Customer - Narrative (Details) $ in Millions	9 Months Ended
	Sep. 30, 2020 USD ($) segment	Dec. 31, 2019 USD ($)
Disaggregation of Revenue
Contract with customer, asset, after allowance for credit loss	$ 8	$ 10
Revenue, performance obligation, description of payment terms	30 to 90 days
Contract with customer, liability, current	$ 12	10
Contract with customer, liability, noncurrent	4	12
Contract with customers receivable, current	41	37
Contract with customers receivable, non-current	$ 164	$ 180
Number of reportable segments | segment	2
Minimum
Disaggregation of Revenue
Capitalized contract costs, amortization period	3 years
Maximum
Disaggregation of Revenue
Capitalized contract costs, amortization period	7 years