Stock-Based Compensation - Employee Stock Purchase Plan ("ESPP") - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended				9 Months Ended
	Aug. 31, 2015	Feb. 28, 2015	Aug. 31, 2014	Feb. 28, 2014	Sep. 30, 2015	Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period					6 months
Employee Stock Purchase Plan ("ESPP") [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of fair market value to determine purchase price					85.00%
Proceeds of from issuance of shares under ESPP	$ 0.4	$ 0.4	$ 0.3	$ 0.3
Options issued	76,314	57,293	51,545	49,063
Rate of discount on fair market value of common stock under ESPP					15.00%
Period of expected life, options granted					5 years
Increase number authorized shares						750,000