Basis of Presentation and Significant Accounting Policies - Long-lived Assets (Details) (USD $)	3 Months Ended	12 Months Ended
	Sep. 30, 2010	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Property, Plant and Equipment [Line Items]
Depreciable life		10 years
Capitalized internal use software costs		$ 74,400,000	$ 88,600,000
Capitalized internal use software costs, amortization		76,700,000	56,500,000
Property and equipment, impairment loss	$ 46,500,000	$ 13,640,000	$ 0	$ 46,460,000
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