Leases Lessee Operating Leases (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating Lease, Expense	[1]	$ 646	$ 640	$ 632
Variable Lease, Cost	[2]	164	153	149
Lease, Cost	[3]	$ 810	$ 793	$ 781

[1] Represents the Company's operating lease expense related to its ROU assets for the twelve months ended December 31, 2021, 2020 and 2019.

[2] Represents the Company's expense related to contingent payments for operating leases (such as payments based on revenues derived from the communications infrastructure located on the leased asset) for the twelve months ended December 31, 2021, 2020 and 2019. Such contingencies are recognized as expense in the period they are resolved.

[3] Excludes those direct operating expenses accounted for pursuant to accounting guidance outside the scope of ASC 842.