Common Stock - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended				12 Months Ended	1 Months Ended		12 Months Ended		12 Months Ended
	Jan. 31, 2013	Dec. 31, 2013	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2010	Dec. 31, 2013 Convertible Senior Subordinated Notes [Member] Early Conversion Payment [Member]	Nov. 30, 2013 Archer-Daniels-Midland Company [Member]	Jan. 31, 2013 Archer-Daniels-Midland Company [Member]	Dec. 31, 2013 Archer-Daniels-Midland Company [Member]	Jun. 02, 2011 IPO [Member]	Dec. 31, 2011 Redeemable Convertible Preferred Stock [Member]	Jun. 02, 2011 Redeemable Convertible Preferred Stock [Member]	Jun. 02, 2011 Series B Preferred Stock [Member]
Common Stock Disclosure [Line Items]
Shares issued for initial public offering, net of offering costs			12,021,250
Common stock issuance price										$ 18.00
Proceeds from the issuance of common stock in initial public offering			$ 201,236,000
Underwriting discounts and commissions			15,100,000
Initial public offering costs			4,295,000
Redeemable convertible preferred stock, conversion basis											One for one
Conversion of redeemable convertible preferred stock at initial public offering, shares												34,534,125	303,855
Common stock, shares authorized		150,000,000		150,000,000	60,000,000
Common stock, par value		$ 0.001		$ 0.001	$ 0.001
Preferred stock, shares authorized		5,000,000		5,000,000
Holder of each share of common stock entitled vote		One vote
Percentage of stockholder vote required for adoption, amendment or repeal		66.6667%
Common stock issued pursuant to collaboration agreement							423,278	347,483	770,761
Debt instrument converted into common stock	$ 43,200,000
Number of common shares issued upon early conversion of notes						5,541,597					(34,534,125)