Reclassification of warrant liability to equity.

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Summary Of Significant Accounting Policies [Line Items]

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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)		3 Months Ended
	Jan. 01, 2018	Mar. 31, 2018	Mar. 31, 2017
Summary Of Significant Accounting Policies [Line Items]
Revenue recognition under milestone method		$ 0	$ 0
ASU 2014-09 [Member]
Summary Of Significant Accounting Policies [Line Items]
Cumulative adjustment to retained earnings and accounts receivable	$ 2,900,000
JGB Debt [Member]
Summary Of Significant Accounting Policies [Line Items]
Restricted cash released upon full conversion of debt obligation		$ 9,400,000
JGB Debt [Member] \| ASU 2017-11 [Member]
Summary Of Significant Accounting Policies [Line Items]
Reclassification of warrant liability to equity	$ 6,600,000
Allenex [Member]
Summary Of Significant Accounting Policies [Line Items]
Acquisition date		Apr. 14, 2016
Allenex [Member] \| Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Company ownership percentage		100.00%