Consolidated Statement of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income [Member]	Retained Earnings [Member]
Beginning balance at Sep. 30, 2013	$ 93,817	$ 695	$ 2,028	$ 58	$ 91,036
Beginning balance, shares at Sep. 30, 2013		13,891,000
Net income	12,031				12,031
Other comprehensive income (loss), net of tax	1,470			1,470
Issuance of common stock	269	$ 8	261
Issuance of common stock, shares		163,000
Common stock repurchased	$ (11,541)	$ (25)	(2,330)		(9,186)
Common stock repurchased, shares	(485,777)	(485,000)
Common stock options exercised, net	$ 243	$ 2	241
Common stock options exercised, net, shares	190,434	38,000
Purchase of common stock to pay employee taxes	$ (1,111)		(1,111)
Excess tax benefit from stock-based compensation plans	236		236
Stock-based compensation	3,337		3,337
Ending balance at Sep. 30, 2014	98,751	$ 680	2,662	1,528	93,881
Ending balance, shares at Sep. 30, 2014		13,607,000
Net income	11,947				11,947
Other comprehensive income (loss), net of tax	(1,523)			(1,523)
Issuance of common stock	279	$ 7	272
Issuance of common stock, shares		139,000
Common stock repurchased	(20,000)	$ (42)	(2,485)		(17,473)
Common stock repurchased, shares		(848,000)
Common stock options exercised, net	$ 431	$ 2	429
Common stock options exercised, net, shares	166,422	47,000
Purchase of common stock to pay employee taxes	$ (825)		(631)		(194)
Excess tax benefit from stock-based compensation plans	432		432
Stock-based compensation	2,381		2,381
Ending balance at Sep. 30, 2015	91,873	$ 647	3,060	5	88,161
Ending balance, shares at Sep. 30, 2015		12,945,000
Net income	9,985				9,985
Other comprehensive income (loss), net of tax	1,268			1,268
Issuance of common stock	270	$ 4	266
Issuance of common stock, shares		74,000
Common stock options exercised, net	$ 1,546	$ 10	1,536
Common stock options exercised, net, shares	437,850	196,000
Purchase of common stock to pay employee taxes	$ (1,953)	$ (1)	(1,952)
Purchase of common stock to pay employee taxes, shares		(7,000)
Stock-based compensation	3,844		3,844
Ending balance at Sep. 30, 2016	$ 106,833	$ 660	$ 6,754	$ 1,273	$ 98,146
Ending balance, shares at Sep. 30, 2016		13,208,000