Income Taxes (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Dec. 31, 2016
Income tax expense (benefit) $ 93 $ 316 $ (2,441) $ (9,585)  
Effective income tax rate (as a percent) 2.00% 15.00% 33.00% 1486.00%  
U.S. federal statutory rate (as a percent)     34.00%    
State          
Net operating losses         $ 61,000
Tax credit carryforwards         2,800
Federal          
Net operating losses         59,500
Tax credit carryforwards         $ 7,100