Nature of Operations and Summary of Significant Accounting Policies - Potentially Dilutive Common Shares Excluded from Calculation of Net Loss per Share (Detail) - shares	3 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total potentially dilutive common shares outstanding	6,170,358	6,044,345
Stock options [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total potentially dilutive common shares outstanding	3,107,081	3,621,853
RSUs [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total potentially dilutive common shares outstanding	2,435,521	1,769,588
IDchecker [Member] | Closing shares [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total potentially dilutive common shares outstanding	464,132	652,904
IDchecker [Member] | Earnout shares [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total potentially dilutive common shares outstanding	163,624