Net Loss per Share - Historical Computation of Basic and Diluted Net Loss Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Numerator:
Net loss attributable to Intrexon	$ (32,714)	$ (38,213)	$ (40,663)	$ 27,097	$ 18,831	$ (52,725)	$ (52,043)	$ 4,115	$ (84,493)	$ (81,822)	$ (38,980)
Add: Accretion of dividends on redeemable convertible preferred stock									0	0	(18,391)
Net loss attributable to common shareholders									$ (84,493)	$ (81,822)	$ (57,371)
Denominator:
Weighted average shares outstanding, basic and diluted									111,066,352	99,170,653	40,951,952
Net loss attributable to common shareholders per share, basic and diluted (in usd per share)									$ (0.76)	$ (0.83)	$ (1.40)