Quarterly report pursuant to Section 13 or 15(d)

Income Taxes - Additional Information (Details)

v3.10.0.1
Income Taxes - Additional Information (Details) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Dec. 31, 2017
Income Tax Expense (Benefit), Continuing Operations [Abstract]          
Income tax expense (benefit) $ 142,000 $ 5,484,000 $ 363,000 $ (11,079,000)  
Income tax refund received     0 11,900,000  
Cash paid for income taxes     0 $ 200,000  
Current income taxes receivable 65,240,000   65,240,000   $ 13,006,000
Non-current income taxes receivable         52,097,000
Valuation allowance $ 148,300,000   $ 148,300,000   $ 171,500,000
Earliest Tax Year          
Income Tax Expense (Benefit), Continuing Operations [Abstract]          
Tax years under examination     2013    
Latest Tax Year          
Income Tax Expense (Benefit), Continuing Operations [Abstract]          
Tax years under examination     2017