| Basis of Presentation - Additional Information (Detail) | Mar. 31, 2013
 Station | 
|---|---|
| Schedule Of Significant Accounting Policies [Line Items] | |
| Radio stations to be owned and/or operated across United States | 99 | 
| X | ||||||||||
| 
- Definition Number of Radio Stations No definition available. 
 | 
| X | ||||||||||
| 
- Details 
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