STOCKHOLDER'S EQUITY AND STOCK-BASED COMPENSATION - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Apr. 30, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Stockholders Equity Note [Line Items]
Common stock, shares issued	8,510,000
Common stock, per share	$ 27.00
Proceed from offering	$ 215,800
Compensation expense		$ 5,869	$ 2,042	$ 13,595	$ 5,294
Employee Stock Purchase Plans
Stockholders Equity Note [Line Items]
Number of shares reserved and available for issuance		672,168		672,168
Employee stock purchase plan offering period				6 months
Percentage of price per share				85.00%
Contribution of employee in percentage				10.00%
Contribution of employee in shares		875		875
Compensation expense		$ 87	90	$ 221	$ 177
Shares purchased under plan				30,584	29,051
1995 Equity Incentive Plan (the Equity Plan)
Stockholders Equity Note [Line Items]
Number of shares reserved and available for issuance		6,188,704		6,188,704
Compensation expense		$ 5,782	1,952	$ 13,374	$ 5,117
Stock Compensation Plan
Stockholders Equity Note [Line Items]
Stock based compensation capitalized into inventory		$ 36	$ 22	$ 117	$ 45
Stock Options | 1995 Equity Incentive Plan (the Equity Plan)
Stockholders Equity Note [Line Items]
Vesting period				48 months
Contractual life of option				10 years
Restricted Stock Units (RSUs) | 1995 Equity Incentive Plan (the Equity Plan)
Stockholders Equity Note [Line Items]
Vesting period				4 years