Leases - Schedule of Maturities of Lease Liabilities (Details) $ in Millions	Mar. 31, 2019 USD ($)
Leases [Abstract]
2019	$ 54
2020	65
2021	53
2022	45
2023	33
Thereafter	154
Total lease payments	404
Imputed lease interest	(58)
Total lease liabilities	$ 346