Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Numerator:
Net (loss) income	$ (4,569)	$ 2,357
Denominator:
Denominator for basic net income per common share — weighted average shares outstanding	26,748,000	26,175,000
Effect of dilutive securities:
Stock options and restricted stock units	0	797,000
Denominator for diluted net income per common share — adjusted weighted average shares	26,748,000	26,972,000
Basic net (loss) income per common share:
Net (loss) income, basic (USD per share)	$ (0.17)	$ 0.09
Diluted net (loss) income per common share
Net (loss) income, diluted (USD per share)	$ (0.17)	$ 0.09
Potentially dilutive securities excluded from computation of earnings per share	1,998,740	1,108,900
Excluded incremental common shares related to common stock options and restricted stock units	331,021