Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Convertible Security

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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-Topic 230

-SubTopic 10

-Section 50

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The price per share of the conversion feature embedded in the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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-Topic 835

-SubTopic 30

-Section 55

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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-Section S99

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-Subparagraph (SX 210.5-02.22(a)(2))

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Convertible Note Payable - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions		6 Months Ended
	Jan. 29, 2015	Jun. 30, 2015	Dec. 31, 2014	Oct. 31, 2012	Jul. 31, 2012
Debt Instrument [Line Items]
Conversion date		Oct. 09, 2015
Conversion price per share	$ 4.00	$ 4.00
Convertible note payable, at fair value			$ 23.4
Number of convertible note payable converted in to common stock	1,356,738
Convertible Debt
Debt Instrument [Line Items]
Outstanding principal amount				$ 5.0	$ 5.0
Convertible Debt \| GSK
Debt Instrument [Line Items]
Outstanding principal amount				$ 5.4