Quarterly report pursuant to Section 13 or 15(d)

Restricted Cash (Details)

v3.8.0.1
Restricted Cash (Details) - USD ($)
$ in Thousands
1 Months Ended
Apr. 30, 2018
Mar. 31, 2018
Dec. 31, 2017
Mar. 31, 2017
Dec. 31, 2016
Restricted Cash          
Restricted cash, security deposit   $ 500 $ 500    
Refund received from landlord of security deposit on lease $ 200        
Reconciliation of cash, cash equivalents, and restricted cash          
Cash and cash equivalents   94,334 32,205    
Restricted cash, current   193 193    
Restricted cash   290 290    
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Total   $ 94,817 $ 32,688 $ 48,482 $ 59,071