Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Net income (loss)	$ 6,538	$ 5,089	$ 958	$ (2,695)	$ 1,539	$ 301	$ (3,330)	$ (5,662)	$ 9,890	$ (7,152)	$ (9,486)
Denominator:
Weighted average basic shares (in shares)									11,571	11,507	11,453
Dilutive effect of restricted stock units (in shares)									63	0	0
Weighted average diluted shares with assumed conversions (in shares)									11,634	11,507	11,453
Earnings (loss) per share:
Basic (in dollars per share)	$ 0.56	$ 0.44	$ 0.08	$ (0.23)	$ 0.13	$ 0.03	$ (0.29)	$ (0.49)	$ 0.85	$ (0.62)	$ (0.83)
Diluted (in dollars per share)	$ 0.56	$ 0.44	$ 0.08	$ (0.23)	$ 0.13	$ 0.03	$ (0.29)	$ (0.49)	$ 0.85	$ (0.62)	$ (0.83)