Consolidated Statement Of Stockholders' Equity (USD $) In Thousands, except Share data	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Balance at Sep. 30, 2008	$ 59	$ 42,030	$ 73,780	$ 1,494	$ 117,363
Balance, shares at Sep. 30, 2008	5,936,508
Net income			1,760		1,760
Other comprehensive income (loss)				(1,736)	(1,736)
Excess tax benefit from share - based compensation		147			147
Issuance of common stock pursuant to exercise of options, net of tax	1	840			841
Issuance of common stock pursuant to exercise of options, shares	58,400
Stock-based compensation		283			283
Balance at Sep. 30, 2009	60	43,300	75,540	(242)	118,658
Balance, shares at Sep. 30, 2009	5,994,908
Net income			14,082		14,082
Other comprehensive income (loss)				86	86
Excess tax benefit from share - based compensation		1,128			1,128
Issuance of common stock pursuant to exercise of options, net of tax	1	2,186			2,187
Issuance of common stock pursuant to exercise of options, shares	122,450
Stock-based compensation		445			445
Balance at Sep. 30, 2010	61	47,059	89,622	(156)	136,586
Balance, shares at Sep. 30, 2010	6,117,358				6,117,358
Net income			29,711		29,711
Other comprehensive income (loss)				326	326
Excess tax benefit from share - based compensation		6,896			6,896
Issuance of common stock pursuant to exercise of options, net of tax	3	2,755			2,758
Issuance of common stock pursuant to exercise of options, shares	233,900
Stock-based compensation		736			736
Balance at Sep. 30, 2011	$ 64	$ 57,446	$ 119,333	$ 170	$ 177,013
Balance, shares at Sep. 30, 2011	6,351,258				6,351,258