Debt	3 Months Ended
Mar. 31, 2013
Debt
Debt	7. Debt In November 2012, the Company entered into a Loan and Security Agreement (the “Loan Agreement”) with Hercules Technology Growth Capital, Inc. pursuant to which the Company received loans in the aggregate principal amount of $40.0 million in 2012. The Company’s obligations associated with the Loan Agreement are secured by a security interest in all of the Company’s personal property now owned or hereafter acquired, excluding intellectual property but including the proceeds from the sale, if any, of intellectual property, and a negative pledge on intellectual property. The Loan Agreement provides for interest-only payments for twelve months and repayment of the aggregate outstanding principal balance of the loans in monthly installments starting on December 1, 2013 and continuing through May 1, 2016. However, if the Company receives aggregate gross proceeds of at least $75 million in one or more transactions prior to December 1, 2013, the Company may elect to extend the interest-only period by six months so that the aggregate outstanding principal balance of the loans would be repaid in monthly installments starting on June 1, 2014 and continuing through November 1, 2016. For the three months ended March 31, 2013, interest expense related to the outstanding principal balance of the loans was $1.1 million. Upon full repayment or maturity of the loans, the Company is required to pay a fee of $1.2 million, which is recorded as a long-term liability on the condensed consolidated balance sheets. As of March 31, 2013, the Company had outstanding borrowings of $38.7 million, net of debt discounts of $1.4 million. Amortization of the debt discounts, which are recorded as interest expense, was $0.2 million for the three months ended March 31, 2013. Silver Creek Convertible Notes In December 2012, as described in Note 2 “—Derivative Liability,” the Company’s majority owned subsidiary, Silver Creek, entered into a Note Purchase Agreement pursuant to which it issued convertible notes to various lenders in aggregate principal amounts of $1.6 million in December 2012 and $0.3 million in February 2013. As of March 31, 2013, Silver Creek had outstanding borrowings of $1.6 million, net of debt discounts of $0.2 million. Amortization of the debt discounts, which are recorded as interest expense, was $0.1 million for the three months ended March 31, 2013.

7. Debt

In November 2012, the Company entered into a Loan and Security Agreement (the “Loan Agreement”) with Hercules Technology Growth Capital, Inc. pursuant to which the Company received loans in the aggregate principal amount of $40.0 million in 2012. The Company’s obligations associated with the Loan Agreement are secured by a security interest in all of the Company’s personal property now owned or hereafter acquired, excluding intellectual property but including the proceeds from the sale, if any, of intellectual property, and a negative pledge on intellectual property.

The Loan Agreement provides for interest-only payments for twelve months and repayment of the aggregate outstanding principal balance of the loans in monthly installments starting on December 1, 2013 and continuing through May 1, 2016. However, if the Company receives aggregate gross proceeds of at least $75 million in one or more transactions prior to December 1, 2013, the Company may elect to extend the interest-only period by six months so that the aggregate outstanding principal balance of the loans would be repaid in monthly installments starting on June 1, 2014 and continuing through November 1, 2016. For the three months ended March 31, 2013, interest expense related to the outstanding principal balance of the loans was $1.1 million. Upon full repayment or maturity of the loans, the Company is required to pay a fee of $1.2 million, which is recorded as a long-term liability on the condensed consolidated balance sheets.

As of March 31, 2013, the Company had outstanding borrowings of $38.7 million, net of debt discounts of $1.4 million. Amortization of the debt discounts, which are recorded as interest expense, was $0.2 million for the three months ended March 31, 2013.

Silver Creek Convertible Notes

In December 2012, as described in Note 2 “—Derivative Liability,” the Company’s majority owned subsidiary, Silver Creek, entered into a Note Purchase Agreement pursuant to which it issued convertible notes to various lenders in aggregate principal amounts of $1.6 million in December 2012 and $0.3 million in February 2013. As of March 31, 2013, Silver Creek had outstanding borrowings of $1.6 million, net of debt discounts of $0.2 million. Amortization of the debt discounts, which are recorded as interest expense, was $0.1 million for the three months ended March 31, 2013.