Represents the payment obligation under the collaboration agreement that was triggered by the Company.

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Represents the additional advance that the entity may request at any time after the specified date through December 15, 2012.

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The percentage points subtracted from the alternative interest rate calculation used to compute the variable rate of the debt instrument.

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Represents the amount of final interest payment to be paid under the loan agreement.

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Represents the amount of gross proceeds in one or more transactions prior to December 1, 2013 that the Company may elect to extend the interest-only period by six months so that the aggregate outstanding principal balance of the loan would be repaid in monthly installments starting on June 1, 2014 and continuing through November 1, 2016.

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Represents the initial advance at closing under the debt agreement.

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Represents the period of interest-only payment as provided under the loan agreement.

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Represents the extension period for interest only payments as provided under the loan agreement.

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Represents the stated interest rate used as the basis for calculation of the alternative interest rate.

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No definition available.

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Represents the value of the Company's equity securities sold to institutional accredited investors in a private financing, available for purchase by the lender within one year after the closing of the Loan Agreement.

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Represents the period to purchase equity securities sold to institutional accelerated investors under the Loan Agreement.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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Amount of the fee that accompanies borrowing money under the debt instrument.

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When presenting a range of interest rates, the highest stated (contractual) rate for funds borrowed under the debt agreement as of the balance sheet date.

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When presenting a range of interest rates, the lowest stated (contractual) rate for funds borrowed under the debt agreement as of the balance sheet date.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

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Subsequent Events (Details) (Subsequent event, USD $) In Millions, unless otherwise specified	3 Months Ended	0 Months Ended		0 Months Ended
	Dec. 31, 2012	Nov. 08, 2012 Loan and Security Agreement with Hercules Technology Growth Capital, Inc.	Nov. 08, 2012 Loan and Security Agreement with Hercules Technology Growth Capital, Inc. Maximum	Nov. 08, 2012 Loan and Security Agreement with Hercules Technology Growth Capital, Inc. Minimum	Nov. 08, 2012 Loan and Security Agreement with Hercules Technology Growth Capital, Inc. First alternative interest rate	Nov. 08, 2012 Loan and Security Agreement with Hercules Technology Growth Capital, Inc. Second alternative interest rate
Subsequent Events
Aggregate principal amount available		$ 40.0
Initial advance under Loan Agreement		25.0
Additional term loan advance which is available at any time through December 15, 2012			15.0
Minimum stated percentage rate (as a percent)					10.55%
Stated percentage used as basis for calculation of alternative interest rate						10.55%
Description of reference rate that is added to stated percentage rate in calculation of variable rate						Prime rate
Percentage points subtracted from alternative interest rate						5.25%
Maximum stated percentage rate (as a percent)						12.55%
Period of interest-only payment		12 months
Amount of gross proceeds in one or more transactions prior to December 1, 2013 that the Company may elect to extend the interest-only period by six months				75
Extension period for interest only payments		6 months
Fee paid		0.3
Fee required to be paid		1.2
Net proceeds from loan		24.7
Value of the Company's equity securities available for purchase by the lender		1.0
Period to purchase equity securities sold to institutional accredited investors under the Loan Agreement		1 year
Collaborative agreement, payment triggered by Company	$ 0.6