Stockholders Equity - Additional Information (Detail) - USD ($)													1 Months Ended			12 Months Ended
	Dec. 15, 2015	Jan. 27, 2015	Jan. 21, 2015	Jan. 02, 2015	Dec. 29, 2014	Dec. 15, 2014	Feb. 14, 2014	Feb. 12, 2014	Feb. 10, 2014	Oct. 24, 2012	Oct. 19, 2012	Oct. 18, 2012	Jan. 31, 2015	Jan. 31, 2014	Oct. 31, 2011	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Oct. 04, 2011
Stockholders Equity Note [Line Items]
Common stock, par value																$ 0.0001	$ 0.0001
Issuance of common stock, per share																$ 190.00	$ 122.50
Net proceeds from issuance of common stock																$ 205,133,000	$ 129,440,000
Issuance of common stock on exercise of option																757,038	430,490	314,623
Common stock, shares authorized																100,000,000	100,000,000
Shares of stock authorized before amendment																110,000,000
Preferred stock, shares authorized																10,000,000
Preferred stock, par value																$ 0.0001
Equity method investment ownership percentage																				100.00%
Common stock, shares outstanding																32,466,842	30,548,309
Warrant expiration date																Apr. 10, 2021
Shares cancelled																2,943
Issuance of common stock on exercise of option																5,542,285	3,978,126	2,604,224	1,906,334
Weighted-average grant date fair value of options granted																$ 68.30	$ 101.17	$ 29.94
Receivables from the exercise of options																$ 0	$ 835,000
Net proceeds from exercise of options				$ 835,000												$ 28,228,000	$ 6,533,000	$ 2,215,000
2011 Incentive Award Plan
Stockholders Equity Note [Line Items]
Common stock shares reserved for issuance																10,529,412
Issuance of common stock on exercise of option																5,542,285
Common stock are available for future issuance																3,452,346
Employees
Stockholders Equity Note [Line Items]
Issuance of common stock on exercise of option					43,400
Performance Awards
Stockholders Equity Note [Line Items]
Shares issued to the employees	6,530					4,965
Shares cancelled	2,943					4,504
Estimated unrecognized employee compensation cost related to non-vested stock options granted																$ 400,000
Estimated unrecognized employee compensation cost related to non-vested stock options granted, Weighted-average period of recognition																1 year
Performance Awards | Employees
Stockholders Equity Note [Line Items]
Common stock price														$ 102.46
Performance share expense recognition period														3 years
Non Vested Stock Options
Stockholders Equity Note [Line Items]
Estimated unrecognized employee compensation cost related to non-vested stock options granted																$ 225,200,000
Estimated unrecognized employee compensation cost related to non-vested stock options granted, Weighted-average period of recognition																2 years 2 months 12 days
Maximum | 2011 Incentive Award Plan
Stockholders Equity Note [Line Items]
Stock options granted, term																10 years
Maximum | Performance Awards
Stockholders Equity Note [Line Items]
Number of shares granted to employees																	28,411
Maximum | Performance Awards | Employees
Stockholders Equity Note [Line Items]
Common stock price														$ 47.53
Number of shares granted to employees														28,411
President
Stockholders Equity Note [Line Items]
Percentage of shares held by related party															21.00%
Common Stock
Stockholders Equity Note [Line Items]
Issuance of common stock (in shares)																1,150,000	1,126,530
Issuance of common stock on exercise of option																757,038	430,490	314,623
Common stock, shares outstanding																32,466,842	30,548,309	28,991,289	28,676,666
Shares of common stock that could be acquired by warrant																2,116,250
Common stock price																$ 16
Common Stock | President
Stockholders Equity Note [Line Items]
Common stock, shares outstanding															18,666,733
Common Stock | President | Minimum
Stockholders Equity Note [Line Items]
Minimum ownership percentage of outstanding shares of common stock the president need to maintain after issuance of warrants															20.00%
Underwritten Public Offering
Stockholders Equity Note [Line Items]
Issuance of common stock (in shares)			1,000,000						979,592			7,500,000
Common stock, par value			$ 0.0001						$ 0.0001			$ 0.0001
Issuance of common stock, per share			$ 190.00						$ 122.50			$ 16.00
Net proceeds from issuance of common stock		$ 205,100,000					$ 129,400,000			$ 129,200,000			$ 205,100,000
Gross proceeds from issuance of common stock		218,500,000					138,000,000			138,000,000
Public offering, underwriting discount and estimated offering expenses		$ 13,400,000					$ 8,600,000			$ 8,800,000
Overallotment Option Exercise by Underwriters
Stockholders Equity Note [Line Items]
Issuance of common stock (in shares)			150,000					146,938			1,125,000