Leases Liability Maturity (Details) $ in Millions	Mar. 31, 2019 USD ($)
Leases [Abstract]
Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year	$ 173
Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months	181
Lessee, Operating Lease, Liability, Payments, Due Year Two	150
Lessee, Operating Lease, Liability, Payments, Due Year Three	121
Lessee, Operating Lease, Liability, Payments, Due Year Four	86
Lessee, Operating Lease, Liability, Payments, Due Year Five	48
Lessee, Operating Lease, Liability, Payments, Due after Year Five	224
Lessee, Operating Lease, Liability, Payments, Due	983
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	166
Operating Lease, Liability	$ 817