Fair Value of Financial Instruments - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Jul. 03, 2017	Aug. 31, 2016
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Principal amount of outstanding notes and other debt	$ 4,641,617		$ 4,626,887
Estimated fair value of future contingent consideration	89,236		$ 105,762
Payments of contingent consideration	12,662	$ 18,791
Increase (decrease) in fair value of contingent consideration liability	(3,864)	10,910
Hunt Telecommunications, LLC
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Estimated fair value of future contingent consideration	10,500			$ 16,400
Tower Cloud, Inc.
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Estimated fair value of future contingent consideration	78,700
Payments of contingent consideration	12,700	$ 18,800
Tower Cloud, Inc. | Minimum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Percentage of aggregate amount of contingent consideration payments					50.00%
Prices with Other Observable Inputs (Level 2)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Notes and other debt, fair value	$ 4,400,000