Income Taxes (Components of Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Property and equipment	$ 334	$ 167,491
Deferred site rental receivable	5,742	18,320
Intangible assets	0	102,624
Total deferred income tax liabilities		(13,200)
Deferred Tax Liabilities, Gross	6,076	288,435
Deferred Tax Assets, Goodwill and Intangible Assets	40,654
Net operating loss carryforwards	7,891	133,096
Deferred ground lease payable	1,312	1,627
Accrued liabilities	4,183	158,813
Receivable allowance	196	1,459
Other	1,252	1,278
Valuation allowance, asset	(1,994)	(21,038)
Total deferred income tax assets, net	53,494	275,235
Deferred Tax Assets, Net	47,418
Domestic Tax Authority [Member]
Valuation allowance, asset	0	(3,000)
Deferred Tax Assets, Net	48,273	3,557
State and Local Jurisdiction [Member]
Total deferred income tax liabilities		(15,746)
Valuation allowance, asset	0	$ (16,208)
Deferred Tax Assets, Net	$ 1,203
Minimum [Member] | Domestic Tax Authority [Member]
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2024
Minimum [Member] | State and Local Jurisdiction [Member]
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2016
Maximum [Member] | Domestic Tax Authority [Member]
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2032
Maximum [Member] | State and Local Jurisdiction [Member]
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2035