Intangible Assets, Net (Gross and Net Carrying Amounts for each Major Class of Intangible Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 6,761,075	$ 6,064,275
Accumulated amortization	(3,134,302)	(2,732,810)
Net book value	3,626,773	3,331,465
Current Contract Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	4,996,591	4,394,416
Accumulated amortization	(2,218,404)	(1,928,030)
Net book value	2,778,187	2,466,386
Network Location Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	1,764,484	1,669,859
Accumulated amortization	(915,898)	(804,780)
Net book value	$ 848,586	$ 865,079