Leases Operating and Finance Lease Maturities Table (Details) $ in Millions	Mar. 31, 2019 USD ($)
Operating Lease Liabilities, Payments Due [Abstract]
Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year	$ 98
Lessee, Operating Lease, Liability, Payments, Due Year Two	87
Lessee, Operating Lease, Liability, Payments, Due Year Three	68
Lessee, Operating Lease, Liability, Payments, Due Year Four	44
Lessee, Operating Lease, Liability, Payments, Due Year Five	27
Lessee, Operating Lease, Liability, Payments, Due after Year Five	172
Lessee, Operating Lease, Liability, Payments, Due	496
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	194
Operating Lease, Liability	302
Finance Lease Liabilities, Payments, Due [Abstract]
Finance Lease, Liability, Payments, Remainder of Fiscal Year	8
Finance Lease, Liability, Payments, Due Year Two	11
Finance Lease, Liability, Payments, Due Year Three	11
Finance Lease, Liability, Payments, Due Year Four	11
Finance Lease, Liability, Payments, Due Year Five	11
Finance Lease, Liability, Payments, Due after Year Five	38
Finance Lease, Liability, Payments, Due	90
Finance Lease, Liability, Undiscounted Excess Amount	17
Finance Lease, Liability	$ 73