Leases - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Lessee, Lease, Description [Line Items]
Operating lease, renewal term	10 years
Finance lease, right-of-use asset	$ 35	$ 16
Finance lease, right-of-use asset, accumulated depreciation	$ 2	$ 3
Minimum
Lessee, Lease, Description [Line Items]
Operating lease, remaining lease term	1 year
Operating lease, termination period	1 month
Operating lease, lease not yet commenced, term of contract	2 years
Maximum
Lessee, Lease, Description [Line Items]
Operating lease, remaining lease term	14 years
Operating lease, termination period	2 years
Operating lease, lease not yet commenced, term of contract	5 years