Basis of Presentation and Significant Accounting Policies - (Details) (USD $) Share data in Millions, unless otherwise specified	3 Months Ended	12 Months Ended			0 Months Ended
	Jun. 30, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Mar. 04, 2014 Subsequent Event [Member]	Dec. 31, 2013 High [Member]	Dec. 31, 2013 Low [Member]
Finite-Lived Intangible Assets [Line Items]
Regulatory fees and telecommunications taxes separately billed and collected from customers		$ 2,600,000	$ 9,400,000	$ 32,600,000
Restricted Cash, Cash Equivalents and Short-Term Investments
Restricted cash, cash equivalents and short-term investments, included in other current assets		900,000	700,000
Restricted cash, cash equivalents and short-term investments, included in other assets		11,300,000	11,400,000
Equity method investment, ownership percentage						50.00%	20.00%
Equity method investment, ownership percentage, outstanding membership units, minimum		4.00%
Equity method investment, ownership percentage, outstanding membership units, maximum		20.70%
Equity method investments		0	10,600,000
Equity in net income (loss) of investees, net		(1,400,000)
Equity in net income (loss) of investees, net		(10,558,000)	(464,000)	2,984,000
Dividends received from equity investee	18,200,000
Equity method investment, dividends or distributions, operating activities				6,600,000
Dividends received from equity investee				11,606,000
Equity method investment, impairment		9,200,000
Contingent asset received from sale of equity method investment					5,000,000
Operating leases, rent expense		252,600,000	256,300,000	260,600,000
Advertising expense		$ 85,500,000	$ 131,200,000	$ 115,800,000
Antidilutive securities excluded from computation of earnings per share, amount		8.7	8.4	7.8