Leases - Other Information (Details) $ in Millions	9 Months Ended
	Sep. 30, 2019 USD ($)
Leases [Abstract]
Operating cash flows for operating leases	$ 101
Financing cash flows for finance leases	13
Non-cash change in lease liabilities arising from obtaining new right of use assets or modifications, operating leases	16
Non-cash change in lease liabilities arising from obtaining new right of use assets or modifications, finance leases	$ 10
Weighted-average remaining lease term (in years)
Operating leases, weighted-average lease term	10 years 2 months 12 days
Finance leases, weighted-average lease term	3 years 7 months 6 days
Weighted-average discount rate
Operating leases, weighted-average discount rate	4.50%
Finance leases, weighted-average discount rate	2.40%