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

No definition available.

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- Definition

Represents the amount of debt discount that was recorded as a long-term liability to be paid upon full repayment or maturity of the loan that has yet to be amortized.

+ References

No definition available.

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- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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- Definition

Increase of additional borrowings on existing and new debt instruments.

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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

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- Definition

Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Debt (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended		3 Months Ended	6 Months Ended
	Feb. 28, 2013	Dec. 31, 2012	Jun. 30, 2013	Jun. 30, 2013
Loan and Security Agreement
Debt
Period of interest-only payment				12 months
Interest expense			$ 1.0	$ 2.1
Discount on loan recorded as a non-current liability to be paid upon full repayment or maturity of the loans			1.2	1.2
Outstanding borrowings			38.8	38.8
Debt discounts			1.2	1.2
Amortization of the debt discounts			0.2	0.3
Loan and Security Agreement \| Hercules
Debt
Aggregate principal amount of loans received		40.0
Convertible notes \| Silver Creek
Debt
Outstanding borrowings			1.7	1.7
Debt discounts			0.1	0.1
Amortization of the debt discounts			0.1	0.1
Aggregate principal amounts	$ 0.3	$ 1.6