Leases - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2019
Lessee, Lease, Description [Line Items]
Right-of-use assets	$ 34
Difference between undiscounted cash flows for operating leases	$ 4
Lease liabilities			$ 35
Weighted average lease term (in years)	6 years 8 months 12 days
Weighted average discount rate (as a percentage)	5.43%
Rental costs	$ 6	$ 9
Other Assets
Lessee, Lease, Description [Line Items]
Right-of-use assets	31
Other Current Liabilities
Lessee, Lease, Description [Line Items]
Operating Lease, Liability, Current	7
Other Liabilities
Lessee, Lease, Description [Line Items]
Operating Lease, Liability, Noncurrent	27
Field equipment
Lessee, Lease, Description [Line Items]
Rental costs	5	7
Buildings
Lessee, Lease, Description [Line Items]
Rental costs	$ 1	$ 2
Minimum | Field equipment
Lessee, Lease, Description [Line Items]
Expected lease term (in years)	3 years
Contractual base terms (in years)	1 year
Minimum | Buildings
Lessee, Lease, Description [Line Items]
Contractual base terms (in years)	7 years