Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Line Items]
Increase in valuation allowance, deferred tax assets	$ 22,300,000	$ 13,800,000
Deferred capitalized start up expense net of amortization	1,000,000	1,200,000
Deferred income tax amortization	900,000	800,000
Net operation loss carryforwards deduction related to equity compensation	$ 900,000	900,000
Changes in ownership interest rate period	3 years
Cumulative changes in ownership interest of shareholders	50.00%
Unrecognized tax benefits	$ 0	0	$ 0
Income tax penalties and interest accrued associated with unrecognized tax benefits	0	0	0
Income tax penalties and interest expense associated with unrecognized tax benefits	0	0	$ 0
Federal
Income Tax Disclosure [Line Items]
Net operating loss carryforwards	140,500,000	84,200,000
State
Income Tax Disclosure [Line Items]
Net operating loss carryforwards	$ 111,900,000	$ 83,700,000
Operating Loss Carryforwards Expiration Year	2035
Federal and State | Research and Development
Income Tax Disclosure [Line Items]
Tax credit carryforwards	$ 2,000,000
Earliest Tax Year
Income Tax Disclosure [Line Items]
NOL and R&D tax credit carry forward expiration year	2027
Latest Tax Year
Income Tax Disclosure [Line Items]
NOL and R&D tax credit carry forward expiration year	2035