Leases Lease-Related Assets and Liabilities (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Operating lease right-of-use assets	$ 1,349,000,000	$ 0
Finance lease right-of-use assets	779,000,000
Finance Lease, Right of Use Asset, Accumulated Depreciation	455,000,000
Total lease assets	2,128,000,000
Current operating lease liabilities	353,000,000	0
Finance lease, current maturities of long-term debt	85,000,000
Noncurrent operating lease liabilities	978,000,000	$ 0
Finance lease, long-term debt less current maturities	542,000,000
Total lease liabilities	1,958,000,000
Operating Lease
Current operating lease liabilities	353,000,000
Noncurrent operating lease liabilities	978,000,000
Finance Lease
Finance lease, current maturities of long-term debt	85,000,000
Finance lease, long-term debt less current maturities	$ 542,000,000