Leases - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Lessee, Lease, Description [Line Items]
Right-of-use assets	$ 121	$ 114	$ 0
Lease liabilities	$ 135	$ 124	$ 0
Minimum
Lessee, Lease, Description [Line Items]
Operating lease, contract term	1 year
Operating lease, renewal term	3 years
Maximum
Lessee, Lease, Description [Line Items]
Operating lease, contract term	9 years
Operating lease, renewal term	5 years