Basis of Presentation and Significant Accounting Policies - Long-lived Assets (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]
Depreciable life	10 years
Capitalized internal use software costs	$ 41,500,000	$ 74,400,000
Capitalized internal use software costs, amortization	84,600,000	76,700,000
Property and equipment, impairment loss	$ 19,847,000	$ 13,640,000	$ 0
Switch Power Equipment [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	15 years
Towers [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	15 years
Antenne [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	5 years
Minimum [Member] | Switches [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	5 years
Minimum [Member] | Cell Site Equipment and Site Improvements [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	5 years
Minimum [Member] | Computer Hardware and Software [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	3 years
Minimum [Member] | Furniture, Fixtures Retail and Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	3 years
Maximum [Member] | Switches [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	10 years
Maximum [Member] | Cell Site Equipment and Site Improvements [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	7 years
Maximum [Member] | Computer Hardware and Software [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	5 years
Maximum [Member] | Furniture, Fixtures Retail and Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Depreciable life	7 years