Property and Equipment, Net (Property and Equipment, Net (Including Assets Held Under Capital Leases)) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 6,034,590	$ 5,985,780
Less: accumulated depreciation	(3,366,586)	(3,191,178)
Property and equipment, net	2,668,004	2,794,602
Towers and Related Components [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	5,142,440	5,164,104
Construction-In-Process [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	36,642	33,644
Furniture, Equipment and Vehicles [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	51,545	51,654
Land, Buildings and Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 803,963	$ 736,378