Significant Events - Additional Information (Details) (USD $)	0 Months Ended
	Aug. 09, 2013	Aug. 31, 2013
Long-term Purchase Commitment [Line Items]
Call option, maximum ownership interest allowed to be exercised by radio operator	30.00%
Period for payment to be expensed	3 months
NextRadio LLC
Long-term Purchase Commitment [Line Items]
Agreement amount	$ 15,000,000
Period of agreement	3 years
Agreement, quarterly payment	3,750,000
Variable interest entity, consolidated, carrying amount of assets		600,000
Variable interest entity, liabilities		0
Emmis
Long-term Purchase Commitment [Line Items]
Agreement, quarterly payment	$ 800,000
Minimum | NextRadio LLC
Long-term Purchase Commitment [Line Items]
Minimum number of devices with pre-loaded smartphone application	30,000,000