Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Related Party Transactions - Additional Information (Detail) - Amunix Inc. [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Related Party Transaction [Line Items]
Additional consideration, milestone payments			$ 30.0
Operating expenses from related party transaction	$ 0.8	$ 0.8	$ 0.3
Due to related party	$ 0.1	$ 0.2
Preferred stock [Member]
Related Party Transaction [Line Items]
Ownership percentage			10.00%
Common Stock [Member] \| Maximum [Member]
Related Party Transaction [Line Items]
Ownership percentage	5.00%