Work Force Reduction and CEO Transition - Additional Information (Details)
$ in Thousands
12 Months Ended
Dec. 31, 2016
USD ($)
position
Restructuring Reserve [Roll Forward]  
Beginning balance $ 11
Payments (721)
Ending balance $ 2,014
Work Force Reduction  
Restructuring Cost and Reserve [Line Items]  
Number of positions eliminated | position 62
Restructuring Reserve [Roll Forward]  
Severance and benefit related costs $ 1,479
CEO Transition  
Restructuring Reserve [Roll Forward]  
Severance and benefit related costs 1,245
CEO Transition | CEO  
Restructuring Reserve [Roll Forward]  
Severance and benefit related costs $ 0