Segment Data (Schedule of Segment Reporting Information) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Segment Reporting Information [Line Items]
Revenues		$ 589,305	$ 522,940	$ 1,713,696	$ 1,547,231
Cost of revenues		140,023	121,519	405,682	348,537
Operating profit		449,282	401,421	1,308,014	1,198,694
Selling, general, and administrative expenses	[1]	51,000	48,152	156,546	146,856
Acquisition and new business initiatives related adjustments and expenses		5,730	4,124	17,525	12,557
Asset impairment and decommission costs		9,860	8,506	18,560	29,103
Depreciation, amortization and accretion		170,916	180,302	530,266	541,587
Operating income (loss)		211,776	160,337	585,117	468,591
Other income (expense) (principally interest expense and other expense)		(174,812)	(147,102)	(380,903)	(626,873)
Income (loss) before income taxes		36,964	13,235	204,214	(158,282)
Cash capital expenditures		92,935	109,256	1,279,926	296,163
Assets		9,668,082		9,668,082		$ 9,158,018
Domestic Site Leasing [Member]
Segment Reporting Information [Line Items]
Revenues		426,758	390,961	1,249,291	1,165,322
Cost of revenues		65,260	64,228	194,455	192,226
Operating profit		361,498	326,733	1,054,836	973,096
Selling, general, and administrative expenses		27,983	25,466	85,240	78,021
Acquisition and new business initiatives related adjustments and expenses		2,911	2,458	10,839	8,059
Asset impairment and decommission costs		6,113	6,129	12,674	22,297
Depreciation, amortization and accretion		123,705	135,350	390,730	403,725
Operating income (loss)		200,786	157,330	555,353	460,994
Cash capital expenditures		39,062	89,982	1,186,791	229,795
Assets		6,638,499		6,638,499		5,893,636
International Site Leasing [Member]
Segment Reporting Information [Line Items]
Revenues		108,734	95,804	315,523	296,201
Cost of revenues		33,406	28,494	95,055	87,894
Operating profit		75,328	67,310	220,468	208,307
Selling, general, and administrative expenses		9,272	8,747	26,553	25,713
Acquisition and new business initiatives related adjustments and expenses		2,819	1,666	6,686	4,498
Asset impairment and decommission costs		3,747	2,377	5,740	6,806
Depreciation, amortization and accretion		45,035	42,851	132,900	131,474
Operating income (loss)		14,455	11,669	48,589	39,816
Cash capital expenditures		51,897	17,971	87,572	61,605
Assets		2,768,258		2,768,258		2,955,563
Site Development [Member]
Segment Reporting Information [Line Items]
Revenues		53,813	36,175	148,882	85,708
Cost of revenues		41,357	28,797	116,172	68,417
Operating profit		12,456	7,378	32,710	17,291
Selling, general, and administrative expenses		4,791	4,518	14,574	13,468
Depreciation, amortization and accretion		565	578	1,727	1,791
Operating income (loss)		7,100	2,282	16,409	2,032
Cash capital expenditures		221	127	1,812	1,191
Assets		79,432		79,432		61,729
Other [Member]
Segment Reporting Information [Line Items]
Selling, general, and administrative expenses		8,954	9,421	30,179	29,654
Asset impairment and decommission costs				146
Depreciation, amortization and accretion		1,611	1,523	4,909	4,597
Operating income (loss)		(10,565)	(10,944)	(35,234)	(34,251)
Other income (expense) (principally interest expense and other expense)		(174,812)	(147,102)	(380,903)	(626,873)
Cash capital expenditures		1,755	$ 1,176	3,751	$ 3,572
Assets		$ 181,893		$ 181,893		$ 247,090

[1] Includes non-cash compensation of $16,589 and $16,606 for the three months ended September 30, 2021 and 2020, respectively, and $57,249 and $50,291 for the nine months ended September 30, 2021 and 2020, respectively.