Income Taxes - Additional Information (Details Textual) - USD ($)		12 Months Ended
	Jan. 01, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Valuation Allowance		$ 81,964,000	$ 71,464,000	$ 71,464,000
Operating Loss Carryforwards, Excess Tax Benefits Related To Share-Based Compensation		$ 1,976,000
Percentage of Holding by Stockholders Under Consideration to Offset Future Taxable Income		stockholders that hold 5% or more of the Company’s common stock
Probability of Realization of Income Tax upon Settlement		50.00%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	34.00%	34.00%	34.00%
Unrecognized Tax Benefits		$ 0	$ 0	$ 0	$ 0
Domestic Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards		$ 306,800,000
Net operating loss carryforwards, Expiration date		Jan. 01, 2025
State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards		$ 215,000,000
Net operating loss carryforwards, Expiration date		Jan. 01, 2019