Annual report pursuant to Section 13 and 15(d)

Income Taxes - Additional Information (Details)

v3.8.0.1
Income Taxes - Additional Information (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Income Tax Disclosure [Abstract]    
Unfavorable impact to gross U.S. deferred tax assets $ 30,600  
Favorable impact to the valuation allowance 30,600  
Federal 19,423 $ 4,230
State 522 0
Foreign 1,694 $ 0
Increase in valuation allowance $ 24,500