Accounts Receivable (Tables)
 3 Months Ended
Mar. 31, 2015
Receivables [Abstract]  
Components of Accounts Receivable
The components of accounts receivable are as follows (in thousands):
 
As of
March 31,
2015
 
December 31, 2014
Trade receivables
$
41,469

 
$
45,719

Allowance for doubtful accounts
(5,376
)
 
(5,837
)
    Total accounts receivable
$
36,093

 
$
39,882