Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Line Items]
Income tax refund	$ 1,100,000		$ 500,000
Federal statutory rate	35.00%	35.00%	35.00%
Net operating losses, reduction for cancellation of indebtedness income realized	$ 31,700,000
Valuation allowance	146,330,000
Interest or penalties related to an uncertain tax position	0
Federal
Income Taxes [Line Items]
Income taxes paid	0	$ 0	$ 0
Operating loss carryforwards	664,800,000
State
Income Taxes [Line Items]
Operating loss carryforwards, valuation allowance		$ 189,200,000
Operating loss carryforwards	$ 246,800,000