Segment Data - Segment Reporting Information Disclosure (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Segment Reporting Information [Line Items]
Revenues	$ 324,305	$ 229,147	$ 637,377	$ 421,637
Cost of revenues	103,725	66,205	204,420	118,398
Depreciation, amortization and accretion	141,089	93,998	266,725	176,098
Operating income (loss)	49,534	34,738	106,300	75,027
Capital expenditures	81,210	925,170	327,611	1,001,469
Assets	6,484,506	6,595,617	6,484,506	6,595,617	6,595,617
Operating Segments [Member] | Site Leasing Revenue [Member]
Segment Reporting Information [Line Items]
Revenues	279,501	203,581	553,005	376,504
Cost of revenues	67,784	44,759	135,885	80,166
Depreciation, amortization and accretion	140,142	93,108	264,750	174,434
Operating income (loss)	49,751	35,550	101,344	77,804
Capital expenditures	80,107	923,070	324,246	998,486
Assets	6,146,675	6,422,577	6,146,675	6,422,577
Operating Segments [Member] | Site Development [Member]
Segment Reporting Information [Line Items]
Revenues	44,804	25,566	84,372	45,133
Cost of revenues	35,941	21,446	68,535	38,232
Depreciation, amortization and accretion	472	519	1,031	1,035
Operating income (loss)	6,448	835	10,930	890
Capital expenditures	839	1,754	2,647	2,267
Assets	73,760	58,804	73,760	58,804
Not Identified by Segment [Member]
Segment Reporting Information [Line Items]
Depreciation, amortization and accretion	475	371	944	629
Operating income (loss)	(6,665)	(1,647)	(5,974)	(3,667)
Capital expenditures	264	346	718	716
Assets	$ 264,071	$ 114,236	$ 264,071	$ 114,236