Leases - Narrative (Details) $ in Millions		12 Months Ended
	Jan. 01, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 mi
Lessee, Lease, Description [Line Items]
Number of miles of land and integral equipment leased | mi			137
Additional lease term			50 years
Percentage of annual increase in operating lease payments			2.50%
Right-of-use asset recognized as non-cash asset addition	$ 534	$ 51
Cash paid for amounts included in measurement of operating lease liabilities		$ 60
Maximum
Lessee, Lease, Description [Line Items]
Term of lease agreements (up to)		50 years
Maximum | Other parties
Lessee, Lease, Description [Line Items]
Term of lease agreements (up to)		50 years