Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Numerator:
Net income (loss)	$ 1,265	$ 1,316	$ 2,955	$ (1,535)
Denominator:
Denominator for basic net income (loss) per share - weighted-average outstanding shares (shares)	12,036	11,889	11,999	11,863
Effect of dilutive securities:
Stock options and restricted stock (shares)	1,051	997	1,031	0
Denominator for diluted net income (loss) per share - weighted-average outstanding shares (shares)	13,087	12,886	13,030	11,863
Net income per share, basic (in dollars per share)	$ 0.11	$ 0.11	$ 0.25	$ (0.13)
Net income per share - diluted (in dollars per share)	$ 0.10	$ 0.10	$ 0.23	$ (0.13)