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Amount of increase in additional paid in capital (APIC) resulting from the issuance of warrants. Includes allocation of proceeds of debt securities issued with detachable stock purchase warrants.

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Face amount or stated value per share of common stock.

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Number of shares issued for each share of convertible preferred stock that is converted.

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Amount of expense (income) related to adjustment to fair value of warrant liability.

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The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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Number of shares under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event.

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Per share amount of par value or stated value of stock classified as temporary equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable.

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Securities Purchase Agreement - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended	1 Months Ended	12 Months Ended			0 Months Ended
	Nov. 17, 2014	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 08, 2014	Nov. 16, 2014
Changes In Equity And Comprehensive Income Line Items [Line Items]
Common stock shares issued at par value (per share)		$ 0.001	$ 0.001	$ 0.001
Warrants to purchase common stock sold (shares)						4,117,647
Exercise price per share						2.26
Proceeds from the issuances of Series C preferred and common stock, net of issuance costs			$ 14,163	$ 0	$ 0
Common stock, shares authorized	100,000,000us-gaap_CommonStockSharesAuthorized	100,000,000us-gaap_CommonStockSharesAuthorized	100,000,000us-gaap_CommonStockSharesAuthorized	100,000,000us-gaap_CommonStockSharesAuthorized			50,000,000us-gaap_CommonStockSharesAuthorized
Reclassification of warrant liability to equity	8,219	8,219	8,219
Expense on fair value warrants			3,280us-gaap_FairValueAdjustmentOfWarrants	0us-gaap_FairValueAdjustmentOfWarrants	0us-gaap_FairValueAdjustmentOfWarrants
Common stock shares reserved for issuance		14,660,000	14,660,000	10,209,000
2009 Omnibus Incentive Compensation Plan
Changes In Equity And Comprehensive Income Line Items [Line Items]
Unreserved shares previously approved for issuance						1,651,455
2000 Stock Compensation Plan
Changes In Equity And Comprehensive Income Line Items [Line Items]
Unreserved shares previously approved for issuance						1,300,000
Series C Preferred Stock
Changes In Equity And Comprehensive Income Line Items [Line Items]
Number of shares sold						87,196
Convertible preferred stock par value per share						0.001
Number of shares sold, Per share price						17.50
Proceeds from the issuances of Series C preferred and common stock, net of issuance costs						14,400
Convertible Preferred Stock, Shares Issued upon Conversion						10
Beneficial conversion feature						445
Series C Convertible Preferred Stock
Changes In Equity And Comprehensive Income Line Items [Line Items]
Common stock shares reserved for issuance						871,960
Scenario, Plan
Changes In Equity And Comprehensive Income Line Items [Line Items]
Common stock, shares authorized						100,000,000
Common Stock
Changes In Equity And Comprehensive Income Line Items [Line Items]
Number of shares sold			7,363,000			7,363,334
Common stock shares issued at par value (per share)						0.001
Number of shares sold, Per share price						1.75
Common stock warrants outstanding
Changes In Equity And Comprehensive Income Line Items [Line Items]
Warrants to purchase common stock sold (shares)						4,117,647
Exercise price per share						2.26