Accounts Receivable (Tables)
 12 Months Ended
Dec. 31, 2013
Receivables [Abstract]  
Changes in Allowance for Doubtful Accounts

The following are the changes in the allowance for doubtful accounts:

 

     Year Ended December 31,  
     2013     2012     2011  
     (In Thousands)  

Balance at beginning of year

    $ 250      $ 300      $ 595   

Provisions for doubtful accounts

      39        21        —     

Charge-offs, net of recoveries

      (139 )      (71 )      (295 ) 
  

 

 

    

 

 

    

 

 

  

Balance at end of year

    $ 150      $ 250      $ 300