Commitments and Contingencies Asset Retirement Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Asset Retirement Obligations [Line Items]
Accretion expense	$ 11,300	$ 9,900	$ 9,200
Other long-term liabilities	2,087,229	1,948,636
Estimated future undiscounted cash flows expected to be paid relating to asset retirement obligations	$ 1,200,000
Subject to Capital Lease with Sprint, TMO, or AT&T [Member]
Asset Retirement Obligations [Line Items]
Tower count as a percentage of total towers	53.00%
asset retirement obligations [Member]
Asset Retirement Obligations [Line Items]
Other long-term liabilities	$ 146,100	$ 132,110