Segment Data - Segment Reporting Information Disclosure (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Segment Reporting Information [Line Items]
Revenues	$ 332,094	$ 238,606	$ 969,470	$ 660,243
Cost of revenues	103,295	71,683	307,715	190,081
Depreciation, amortization and accretion	133,281	101,012	400,006	277,110
Operating income (loss)	63,902	41,071	170,201	116,098
Capital expenditures	125,371	58,216	452,977	1,059,685
Assets	6,584,428	6,595,617	6,584,428	6,595,617	6,595,617
Operating Segments [Member] | Site Leasing Revenue [Member]
Segment Reporting Information [Line Items]
Revenues	287,483	208,828	840,488	585,332
Cost of revenues	68,042	46,621	203,927	126,787
Depreciation, amortization and accretion	132,074	100,107	396,824	274,541
Operating income (loss)	59,547	42,420	161,101	120,224
Capital expenditures	122,268	57,508	446,514	1,056,215
Assets	6,219,735	6,422,577	6,219,735	6,422,577
Operating Segments [Member] | Site Development [Member]
Segment Reporting Information [Line Items]
Revenues	44,611	29,778	128,982	74,911
Cost of revenues	35,253	25,062	103,788	63,294
Depreciation, amortization and accretion	731	561	1,762	1,596
Operating income (loss)	6,685	1,735	17,615	2,625
Capital expenditures	2,538	708	5,185	2,975
Assets	78,738	58,804	78,738	58,804
Not Identified by Segment [Member]
Segment Reporting Information [Line Items]
Depreciation, amortization and accretion	476	344	1,420	973
Operating income (loss)	(2,540)	(3,084)	(8,515)	(6,751)
Capital expenditures	565		1,278	495
Assets	$ 285,955	$ 114,236	$ 285,955	$ 114,236