Leases - Supplemental Balance Sheet Information (Details) - USD ($)	Mar. 31, 2019	Jan. 01, 2019
Lessee, Lease, Description [Line Items]
Operating lease, liability, current		$ 45,000,000
Operating lease, liability, noncurrent		$ 214,000,000
Property and equipment, net
Lessee, Lease, Description [Line Items]
Operating lease, liability, current	$ 0
Finance lease, liability, current	37,000,000
Notes payable
Lessee, Lease, Description [Line Items]
Operating lease, liability, current	0
Finance lease, liability, current	8,000,000
Accrued liabilities
Lessee, Lease, Description [Line Items]
Operating lease, liability, current	45,000,000
Finance lease, liability, current	0
Long-term debt
Lessee, Lease, Description [Line Items]
Operating lease, liability, noncurrent	0
Finance lease, liability, noncurrent	29,000,000
Other liabilities
Lessee, Lease, Description [Line Items]
Operating lease, liability, noncurrent	205,000,000
Finance lease, liability, noncurrent	$ 0