Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income [Member]	Accumulated Deficit [Member]
Beginning Balance (in shares) at Sep. 30, 2012		24,372,000
Beginning Balance at Sep. 30, 2012	$ 69,023	$ 722,345	$ (2,071)	$ 1,376	$ (652,627)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	4,988				4,988
Translation adjustment	247			247
Stock-based compensation (in shares)		475,000
Stock-based compensation	4,027	$ 4,027
Stock option exercises (in shares)		79,000
Stock option exercises	395	$ 395
Issuance of common stock - ESPP (in shares)		344,000
Issuance of common stock - ESPP	$ 1,292	$ 1,292
Issuance of common stock - ODPP (in shares)	4,500	5,000
Issuance of common stock - ODPP	$ 18	$ 18
Issuance of common stock from stock sales (in shares)		4,707,000
Issuance of common stock from stock sales	21,189	$ 21,189
Ending Balance (in shares) at Sep. 30, 2013		29,982,000
Ending Balance at Sep. 30, 2013	101,179	$ 749,266	(2,071)	1,623	(647,639)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	4,852				4,852
Translation adjustment	214			214
Stock-based compensation (in shares)		633,000
Stock-based compensation	4,074	$ 4,074
Stock option exercises (in shares)		120,000
Stock option exercises	573	$ 573
Issuance of common stock - ESPP (in shares)		341,000
Issuance of common stock - ESPP	$ 1,182	$ 1,182
Issuance of common stock - ODPP (in shares)	1,600	2,000
Issuance of common stock - ODPP	$ 8	$ 8
Issuance of common stock - Board of Directors (in shares)		31,000
Issuance of common stock - Board of Directors	$ 265	$ 265
Ending Balance (in shares) at Sep. 30, 2014	31,109,000	31,109,000
Ending Balance at Sep. 30, 2014	$ 112,347	$ 755,368	(2,071)	1,837	(642,787)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	63,100				63,100
Translation adjustment	(990)			(990)
Stock-based compensation (in shares)		948,000
Stock-based compensation	4,320	$ 4,320
Purchase of treasury stock (in shares)		(6,870,000)
Purchase of treasury stock	$ (45,650)	$ 0	(45,650)
Stock option exercises (in shares)	289,467	290,000
Stock option exercises	$ 1,409	$ 1,409
Issuance of common stock - ESPP (in shares)		121,000
Issuance of common stock - ESPP	$ 493	$ 493
Issuance of common stock - ODPP (in shares)	0
Issuance of common stock - Board of Directors (in shares)		78,000
Issuance of common stock - Board of Directors	$ 413	$ 413
Ending Balance (in shares) at Sep. 30, 2015	25,676,000	25,676,000
Ending Balance at Sep. 30, 2015	$ 135,442	$ 762,003	$ (47,721)	$ 847	$ (579,687)