Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Treasury Stock	Accumulated Other Comprehensive Income	Accumulated Deficit
Beginning balance (in shares) at Sep. 30, 2016		26,244,000
Common Stock, Number of Shares [Abstract]
Stock-based compensation (in shares)		432,000
Stock option exercises (in shares)		158,000
Issuance of common stock for acquisition (in shares)		0
Issuance of common stock - Board of Directors (in shares)		61,000
Issuance of common stock - ESPP (in shares)		133,000
Ending balance (in shares) at Sep. 30, 2017		27,028,000
Beginning balance at Sep. 30, 2016		$ 725,666	$ (47,721)	$ 579	$ (571,207)
Common Stock, Number of Shares [Abstract]
Stock-based compensation		3,602
Stock option exercises		534
Tax withholding paid on behalf of employees for stock-based awards		0
Issuance of common stock for acquisition		0
Issuance of common stock - Board of Directors		331
Issuance of common stock - ESPP		773
Translation adjustment	$ (18)			(18)
Net loss	8,235				8,235
Ending balance at Sep. 30, 2017	$ 120,774	$ 730,906	(47,721)	561	(562,972)
Common Stock, Number of Shares [Abstract]
Stock-based compensation (in shares)		372,000
Stock option exercises (in shares)		6,000
Issuance of common stock for acquisition (in shares)		0
Issuance of common stock - Board of Directors (in shares)		0
Issuance of common stock - ESPP (in shares)		171,000
Ending balance (in shares) at Sep. 30, 2018	27,577,000	27,577,000
Common Stock, Number of Shares [Abstract]
Stock-based compensation		$ 3,648
Stock option exercises		28
Tax withholding paid on behalf of employees for stock-based awards		(1,257)
Issuance of common stock for acquisition		0
Issuance of common stock - Board of Directors		0
Issuance of common stock - ESPP		741
Translation adjustment	$ 324			324
Net loss	(17,453)				(17,453)
Ending balance at Sep. 30, 2018	$ 106,805	$ 734,066	(47,721)	885	(580,425)
Common Stock, Number of Shares [Abstract]
Stock-based compensation (in shares)		307,000
Stock option exercises (in shares)	208	1,000
Issuance of common stock for acquisition (in shares)		811,000
Issuance of common stock - Board of Directors (in shares)		0
Issuance of common stock - ESPP (in shares)		197,000
Ending balance (in shares) at Sep. 30, 2019	28,893,000	28,893,000
Common Stock, Number of Shares [Abstract]
Stock-based compensation		$ 2,607
Stock option exercises		1
Tax withholding paid on behalf of employees for stock-based awards		(203)
Issuance of common stock for acquisition		2,951
Issuance of common stock - Board of Directors		0
Issuance of common stock - ESPP		504
Translation adjustment	$ 65			65
Net loss	(35,984)				(35,984)
Ending balance at Sep. 30, 2019	$ 76,746	$ 739,926	$ (47,721)	$ 950	$ (616,409)