Leasing Lease Costs (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Leases [Abstract]
Operating Lease, Cost	$ 137
Finance Lease, Right-of-Use Asset, Amortization	5
Finance Lease, Interest Expense	1
Short-term Lease, Cost	5
Variable Lease, Cost	30
Lease, Cost	$ 178