Leases (Details) - USD ($) $ in Millions	Jul. 01, 2019	Dec. 31, 2019	Jun. 30, 2019
Reclassification of deferred rent in accordance with ASC 842	$ 22
Operating Leases, Future Minimum Payments Due, Next Twelve Months			$ 126
Operating Leases, Future Minimum Payments, Due in Two Years			100
Operating Leases, Future Minimum Payments, Due in Three Years			76
Operating Leases, Future Minimum Payments, Due in Four Years			54
Operating Leases, Future Minimum Payments, Due in Five Years			33
Operating Leases, Future Minimum Payments, Due Thereafter			$ 94
Operating Lease, Weighted Average Remaining Lease Term		6 years 3 months 18 days
Operating Lease, Weighted Average Discount Rate, Percent		2.90%
Minimum
Lessee, Operating Lease, Term of Contract		1 year
Maximum
Lessee, Operating Lease, Term of Contract		23 years