Fair Value Measurements (Summary of Asset Impairment and Decommission Costs) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Fair Value Measurements [Abstract]
Towers and related assets	$ 16,884	$ 3,680	$ 31,241	$ 8,419
Operating lease right-of-use assets	7,479	3,204	15,455	6,255
Write-off of carrying value of decommissioned towers	849	1,733	2,802	2,325
Other (including tower and equipment decommission costs)	7,655	(96)	9,759	34
Total asset impairment and decommission costs	$ 32,867	$ 8,521	$ 59,257	$ 17,033