Quarterly report pursuant to Section 13 or 15(d)

Income Taxes - Additional Information (Details)

v3.10.0.1
Income Taxes - Additional Information (Details) - USD ($)
6 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Dec. 31, 2017
Income Tax Disclosure [Abstract]      
Provision for federal income tax $ 0 $ 0  
Unrecognized tax benefits that would impact effective tax rate 4,500,000   $ 4,500,000
Provision for income tax reflect any adjustment to previously assessed tax act enactment effect $ 0