Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Numerator:
Net income	$ 2,567	$ 2,076	$ 4,381	$ 3,628
Denominator:
Denominator for basic net income (loss) per share - weighted-average outstanding shares (in shares)	12,544	12,299	12,521	12,193
Effect of dilutive securities:
Stock options and restricted stock (in shares)	1,026	704	1,047	693
Denominator for diluted net income (loss) per share - weighted-average outstanding shares (in shares)	13,570	13,003	13,568	12,886
Net income per share - basic (in dollars per share)	$ 0.20	$ 0.17	$ 0.35	$ 0.30
Net income per share - diluted (in dollars per share)	$ 0.19	$ 0.16	$ 0.32	$ 0.28