Summary of Significant Accounting Policies (Details) $ in Thousands, shares in Millions	12 Months Ended
	Dec. 31, 2016 USD ($) years	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($) shares
Fair Value Measurements, Changes in Valuation Techniques	0
Net cash provided by (used from) operating activities	$ (4,547)	$ 3,974	$ 6,148
Net cash provided by (used from) investing activities	10,541	(3,752)	(44)
Net cash provided by (used from) financing activities	(7,931)	16,458	30,011
Capitalized Labor Costs	$ 86,100	36,700	24,200
Useful life of site rental contracts and customer relationships (years)	20 years
Revenue recognition, non-cancelable lease term, minimum (years) | years	5
Revenue recognition, non-cancelable lease term, maximum (years) | years	15
Portion of company site rental costs that are ground lease expenses	0.6667
Ground Lease Agreement Initial Term	5
Percentage of tax position that is likely of being realized upon ultimate settlement	50.00%
Asset write-down charges	$ 34,453	33,468	14,246
Work in Process	$ 49,900	55,300
Deferred Finance Costs, Net		99,300
Wireless Infrastructure [Member]
Estimated useful life, maximum, in years	20 years
Wireless Infrastructure [Member] | Maximum [Member]
Estimated useful life, maximum, in years	20 years
Towers [Member]
Estimated useful life, maximum, in years	20 years
Property, Plant and Equipment [Member]
Asset write-down charges	$ 26,900	27,000	$ 9,300
Other Current Assets [Member]
Straight-Line Site Rental Revenues	67,200	31,100
Deferred Revenue [Domain]
Straight-Line Site Rental Revenues	$ 1,300,000	$ 1,300,000
4.5% Mandatory Convertible Preferred Stock
Antidilutive securities excluded from computation of earnings per share (in shares) | shares		11.4	12.5