Deferred Revenue (Tables)
 12 Months Ended
Dec. 31, 2015
Deferred Revenue Disclosure [Abstract]  
Deferred Revenue, by Arrangement, Disclosure
Deferred revenue consisted of the following (in thousands):
 
As of December 31,
 
2015
 
2014
Subscription
$
18,029

 
$
14,826

Professional services—implementation
5,254

 
2,974

Professional services—communications
3,307

 
2,908

Total current
26,590

 
20,708

Subscription
1,163

 
1,950

Professional services—implementation
5,367

 
4,327

Professional services—communications
992

 
375

Total noncurrent
7,522

 
6,652

Total
$
34,112

 
$
27,360