Quarterly Financial Information Consolidated statement of operations (Details) - USD ($) $ in Thousands		3 Months Ended															6 Months Ended				9 Months Ended				12 Months Ended
		Dec. 31, 2019	[1]	Sep. 30, 2019	Jun. 30, 2019		Mar. 31, 2019		Dec. 31, 2018		Sep. 30, 2018		Jun. 30, 2018		Mar. 31, 2018		Jun. 30, 2019		Jun. 30, 2018		Sep. 30, 2019		Sep. 30, 2018		Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017
Revenues from tenant contracts				$ 171,745	$ 168,189		$ 167,322		$ 167,332		$ 165,108		$ 164,056		$ 162,994		$ 335,511		$ 327,050		$ 507,256		$ 492,158		$ 678,150		$ 659,490		$ 616,897
Other income (expense)				160	288		(3)		133		90		40		(67)		285		(27)		445		63		669		196		287
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest				61,594	57,714		57,736		57,440		54,405		52,563		51,525		115,450		104,088		177,044		158,493		237,103		215,933		174,435
Benefit (provision) for income taxes		$ (119)		(102)	(107)		(98)		(137)		(93)		(93)		(93)		(205)		(186)		(307)		(279)		(426)		(416)		614
Net income (loss)		59,940		61,492	57,607		57,638		57,303		54,312		52,470		51,432		115,245		103,902		176,737		158,214		236,677		215,517		175,049
Amortization of service revenues	[2]			13,436	12,764		12,171		11,974		10,846		10,604		10,067		24,935		20,671		38,371		31,517		52,341		43,491		38,435
Revenues		184,864		185,181	180,953		179,493		179,306		175,954		174,660		173,061		360,446		347,721		545,627		523,675		730,491		702,981		655,332
Site rental costs of operations—third parties(b)	[3]			38,406	38,524		37,282		36,270		37,616		38,355		37,507				75,862		114,212		112,469		152,619		149,748		149,764
Site rental costs of operations—related parties(b)	[3]			10,880	10,721				11,512		10,163		9,700		9,606				19,306		32,210		30,478		43,281		40,981		36,655
Direct Costs of Leased and Rented Property or Equipment	[3]			49,286	49,245				47,782		47,779		48,055		47,113				95,168		146,422		142,947		195,900	[2]	190,729	[2]	186,419	[2]
Management fee—related party				12,611	12,503				12,293		12,207		12,031		11,989				24,020		37,238		36,227		49,837		48,520		46,946
Asset write-down charges				0	185		190		249		0		0		344		375		344		375		344		1,050		593		181
Depreciation, amortization and accretion				51,881	51,626		51,580		51,707		51,684		52,083		52,054		103,206		104,137		155,087		155,821		207,396		207,528		207,764
Costs and Expenses				113,778	113,559		111,785		112,031		111,670		112,169		111,500		225,344		223,669		339,122		335,339		454,183		447,370		441,310
Operating Income (Loss)		$ 69,803		71,403	67,394		67,708		67,275		64,284		62,491		61,561		135,102		124,052		206,505		188,336		$ 276,308		255,611		214,022
Interest Expense and Amortization of Deferred Financing Costs, Third Party				9,969	(9,968)				(9,968)		9,969		9,968		(9,969)		(19,937)		(19,937)		(29,906)		(29,906)
Previously Reported [Member]
Revenues from tenant contracts				171,745	168,189		167,322		167,332		165,108		164,056		162,994		335,511		327,050		507,256		492,158
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest				47,374	44,167		44,783		44,866		42,910		41,311		40,811		88,950		82,122		136,324		125,032				169,898		133,157
Net income (loss)				47,272	44,060		44,685		44,729		42,817		41,218		40,718		88,745		81,936		136,017		124,753				169,482		133,771
Amortization of service revenues				0	0	[2]	0	[2]	0	[2]	0	[2]	0	[2]	0	[2]	0	[2]	0	[2]	0	[2]	0	[2]			0	[2]	0	[2]
Revenues				171,745	168,189		167,322		167,332		165,108		164,056		162,994		335,511		327,050		507,256		492,158				659,490		616,897
Depreciation, amortization and accretion				52,665	52,409		52,362		52,307		52,333		52,731		52,701		104,771		105,432		157,436		157,765				210,072		210,607
Costs and Expenses				114,562	114,342		112,567		112,631		112,319		112,817		112,147		226,909		224,964		341,471		337,283				449,914		444,153
Operating Income (Loss)				57,183	53,847		54,755		54,701		52,789		51,239		50,847		108,602		102,086		165,785		154,875				209,576		172,744
Restatement Adjustment [Member]
Revenues from tenant contracts				0	0		0		0		0		0		0		0		0		0		0
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest				14,172	13,500		12,907		12,529		11,450		11,208		10,671		26,407		21,879		40,579		33,329				45,858		41,145
Net income (loss)				14,172	13,500		12,907		12,529		11,450		11,208		10,671		26,407		21,879		40,579		33,329				45,858		41,145
Amortization of service revenues				13,436	12,764	[2]	12,171	[2]	11,974	[2]	10,846	[2]	10,604	[2]	10,067	[2]	24,935	[2]	20,671	[2]	38,371	[2]	31,517	[2]			43,491	[2]	38,435	[2]
Revenues				13,436	12,764		12,171		11,974		10,846		10,604		10,067		24,935		20,671		38,371		31,517				43,491		38,435
Depreciation, amortization and accretion				(736)	(736)		(736)		(555)		(604)		(604)		(604)		(1,472)		(1,208)		(2,208)		(1,812)				(2,367)		(2,710)
Costs and Expenses				(736)	(736)		(736)		(555)		(604)		(604)		(604)		(1,472)		(1,208)		(2,208)		(1,812)				(2,367)		(2,710)
Operating Income (Loss)				14,172	13,500		12,907		12,529		11,450		11,208		10,671		26,407		21,879		40,579		33,329				45,858		41,145
Other Adjustment [Member]
Revenues from tenant contracts				0	0		0		0		0		0		0		0		0		0		0
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest				48	47		46		45		45		44		43		93		87		141		132				177		133
Net income (loss)				48	47		46		45		45		44		43		93		87		141		132				177		133
Amortization of service revenues				0	0	[2]	0	[2]	0	[2]	0	[2]	0	[2]	0	[2]	0	[2]	0	[2]	0	[2]	0	[2]			0	[2]	0	[2]
Revenues				0	0		0		0		0		0		0		0		0		0		0
Depreciation, amortization and accretion				(48)	(47)		(46)		(45)		(45)		(44)		(43)		(93)		(87)		(141)		(132)				(177)		(133)
Costs and Expenses				(48)	(47)		(46)		(45)		(45)		(44)		(43)		(93)		(87)		(141)		(132)				(177)		(133)
Operating Income (Loss)				$ 48	$ 47		$ 46		$ 45		$ 45		$ 44		$ 43		$ 93		$ 87		$ 141		$ 132				$ 177		$ 133

[1] The sum of quarterly information may not agree to year-to-date information due to rounding. Resta

[2] Represents the amortization of deferred revenues recorded in connection with the CCIC transactions described in note 2 that result in permanent improvements to the Company's towers. The Company receives no cash from, and is not party to, such transactions

[3] Exclusive of depreciation, amortization and accretion shown separately and certain indirect costs included in the management fee.