Notes Payable - Summary of Notes Payable (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Debt Disclosure [Abstract]
Amended and Restated Convertible Notes	$ 32,230	$ 31,576
Amended and Restated Reimbursement Notes	556	600
Amended and Restated Bridge Note	293	1,431
Notes payable, total	33,079	33,607
Less: Current portion	556	33,607
Non-current Notes payable, net of related discounts	$ 32,523

Promissory notes payable.

No definition available.

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Carrying value as of the balance sheet date of the portion of long-term debt due within one year or the operating cycle if longer identified as Convertible Notes Payable. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

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Carrying value as of the balance sheet date of portion of long-term loans payable due within one year or the operating cycle if longer.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Sum of the carrying values as of the balance sheet date of the portions of long-term notes payable due within one year or the operating cycle if longer.

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The amount for notes payable (written promise to pay), payable to related parties, which are due after one year (or one business cycle).

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