Stockholders' Equity - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified				12 Months Ended		12 Months Ended								0 Months Ended				12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Sep. 16, 2011	Dec. 31, 2013 2009 warrants	Dec. 31, 2013 CMP Restated Warrants	Dec. 31, 2013 Radio Holdings Warrants	Dec. 31, 2013 Company Warrants	Dec. 31, 2013 Equity Investment	Sep. 16, 2011 Equity Investment	Dec. 31, 2013 Crestview Warrants	Sep. 16, 2011 Crestview Warrants	Aug. 01, 2011 CMP Acquisition CMP Restated Warrants	Dec. 31, 2013 Citadel Acquisition	Oct. 16, 2013 Class A Common Stock	Dec. 31, 2013 Class A Common Stock	Dec. 31, 2012 Class A Common Stock	Sep. 16, 2011 Class A Common Stock Citadel Acquisition	Dec. 31, 2013 Class A Common Stock Minimum	Dec. 31, 2013 Class B Common Stock	Dec. 31, 2012 Class B Common Stock	Dec. 31, 2013 Class C Common Stock	Dec. 31, 2012 Class C Common Stock	Sep. 15, 2011 Series A Redeemable Preferred Stock	Dec. 31, 2013 Series B Preferred Stock	Oct. 16, 2013 Series B Preferred Stock
Class of Stock [Line Items]
Total stock dividend authorized to issue			1,450,644,871
Common stock, shares authorized															750,000,000	750,000,000			600,000,000	600,000,000	644,871	644,871
Common stock, shares issued														18,860,000	222,399,019	182,682,073	71,700,000		15,424,944	15,424,944	644,871	644,871
Preferred stock, shares authorized			100,000,000																				2,000,000	150,000
Preferred stock, par/stated value	$ 0.01	$ 0.01																					$ 0.01	$ 0.01
Underwriter's over allotment option to purchase shares (shares)														2,460,000
Exercise price per share of underwriters over allotment option to purchase shares														5.00
Net proceeds after underwriting discounts and commissions														$ 89.8
Redemption terms of series A preferred stock, aggregate par value																									$ 78.0
Class A common stock following conversion																		4.99%
Warrants issued				1,300,000
Exercisable price of warrants to purchase common stock				1.17						4.32	4.34
Previously outstanding warrants under Restated Warrant Agreement				600,000	3,700,000		17,200,000					3,700,000
Shares to be issued upon the exercise of 3,700,000 outstanding warrants						8,300,000
Shares converted, shares issued																			8,200,000
Warrants held in reserve for issuance													2,400,000
Company Warrants were converted into shares of Class A common stock since issuance							20,200,000
Warrants outstanding								7,800,000	7,800,000