v3.8.0.1
Income Taxes - Summary of Net Deferred Tax Liability (Details) - USD ($)
$ in Thousands
Dec. 31, 2017
Dec. 31, 2016
Income Tax Disclosure [Abstract]    
Depreciation $ (22,121) $ (30,845)
Inventory (486) (5,807)
Allowance for doubtful accounts 457 738
Uniform capitalization rules 610 932
Other 541 1,009
Deferred income tax liability $ (20,999) $ (33,973)