Deferred Revenue (Details) - USD ($)
$ in Thousands
Dec. 31, 2015
Dec. 31, 2014
Deferred Revenue Arrangement [Line Items]    
Total deferred revenue, current portion $ 22,158 $ 15,540
Total deferred revenue, net of current portion 2,022 3,656
Customer prepayments    
Deferred Revenue Arrangement [Line Items]    
Total deferred revenue, current portion 1,763 3,505
Total deferred revenue, net of current portion 2,022 3,656
Minimum monthly commitment fees    
Deferred Revenue Arrangement [Line Items]    
Total deferred revenue, current portion $ 20,395 $ 12,035