Leases Lease Commitments (Details) $ in Millions	Dec. 31, 2018 USD ($)	[1]
Leases [Abstract]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	$ 169
Operating Leases, Future Minimum Payments, Due in Two Years	99
Operating Leases, Future Minimum Payments, Due in Three Years	72
Operating Leases, Future Minimum Payments, Due in Four Years	56
Operating Leases, Future Minimum Payments, Due in Five Years	38
Operating Leases, Future Minimum Payments, Due Thereafter	78
Operating Leases, Future Minimum Payments Due	$ 512

[1] Includes adjustments for discontinued operations and common control business combination.