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
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-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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The price per share of the conversion feature embedded in the debt instrument.

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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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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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Convertible Note Payable - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
	Jan. 29, 2015	Dec. 31, 2015	Dec. 31, 2014	Oct. 31, 2012
Debt Instrument [Line Items]
Conversion date		Oct. 09, 2015
Convertible note payable, at fair value			$ 23.4
Number of convertible note payable converted in to common stock	1,356,738
Conversion price per share (dolalrs per share)	$ 4.00
Convertible Debt \| GSK
Debt Instrument [Line Items]
Notes payable				$ 5.4