Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Numerator:
Net income	$ 2,928	$ 2,004	$ 2,621	$ 2,212
Denominator:
Denominator for basic net income per common share — weighted average shares outstanding	30,900,000	28,881,000	30,129,000	28,673,000
Effect of dilutive securities:
Stock options and restricted stock units	1,323,000	605,000	1,307,000	912,000
Denominator for diluted net income per common share — adjusted weighted average shares	32,223,000	29,486,000	31,436,000	29,585,000
Basic net income per common share:
Net income, basic (USD per share)	$ 0.09	$ 0.07	$ 0.09	$ 0.08
Diluted net income per common share
Net income, diluted (USD per share)	$ 0.09	$ 0.07	$ 0.08	$ 0.07
Potentially dilutive securities excluded from computation of earnings per share	37,248	713,980	37,248	592,780