Subsequent Event - Additional Information (Detail) (Subsequent Event, Merlin Media LLC, USD $) In Millions, unless otherwise specified	0 Months Ended
	Jan. 04, 2014	Jan. 02, 2014 Station
Subsequent Events [Line Items]
Number of radio stations		2
Monthly management fees payable first year	$ 0.3
Monthly management fees payable second year	0.4
Monthly management fees payable third year	0.5
Monthly management fees payable fourth year	0.6
Call Option
Subsequent Events [Line Items]
Number of radio stations		2
Management fee settlement period under option	4 years
Call Option | Minimum
Subsequent Events [Line Items]
Amount under option to settle management fees	50.0
Call Option | Maximum
Subsequent Events [Line Items]
Amount under option to settle management fees	70.0
Put Option
Subsequent Events [Line Items]
Number of radio stations		2
Period to exercise option	10 years
Amount under option to settle management fees	$ 71.0
Management fee settlement period under option	4 years