Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Components Of Income Tax Expense Benefit [Line Items]
Tax expense/(benefit) at statutory rate - Federal	$ (6,727)us-gaap_CurrentFederalTaxExpenseBenefit	$ (4,188)us-gaap_CurrentFederalTaxExpenseBenefit	$ (5,803)us-gaap_CurrentFederalTaxExpenseBenefit
Tax expense/(benefit) at statutory rate - State	(783)	(488)	(676)
NOL carryforward adjustment per tax return	(687)	0	0
Meals, entertainment and other	13	6	5
Non-deductible stock-based compensation	789	511	518
Fair Market Value adjustment - Warrants	(235)	0	0
Change in valuation allowance	7,630	4,159	5,956
Income tax expense	$ 0us-gaap_IncomeTaxExpenseBenefit	$ 0us-gaap_IncomeTaxExpenseBenefit	$ 0us-gaap_IncomeTaxExpenseBenefit

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Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other deductions.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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