Acquisitions - Schedule of Fair Value Purchase Consideration as of Acquisition Date (Detail) - USD ($) $ in Thousands		12 Months Ended
	Sep. 23, 2014	Dec. 31, 2014	Dec. 31, 2015
Business Acquisition [Line Items]
Contingent consideration payable		$ 117,197	$ 123,008
Total purchase consideration		$ 115,319
Silevo, Inc. [Member]
Business Acquisition [Line Items]
Cash	$ 326
Aggregate fair value of common stock on acquisition date	137,958
Amounts advanced to Silevo prior to acquisition and costs paid on behalf of sellers at acquisition	16,760
Closing consideration payable	413
Contingent consideration payable	115,319
Total purchase consideration	270,908
Silevo, Inc. [Member] | Unvested Restricted Stock Units [Member]
Business Acquisition [Line Items]
Aggregate fair value of common stock on acquisition date	$ 132