Consolidated Statements of Shareholders' Equity (USD $) In Thousands	Total USD ($)	Common Shares Issued [Member]	Additional Paid-in Capital [Member] USD ($)	Retained Earnings [Member] USD ($)	Accumulated Other Comprehensive Income (Loss) [Member] USD ($)
Beginning balance at Sep. 30, 2010	$ 137,361		$ 94,529	$ 42,177	$ 655
Beginning balance, Shares at Sep. 30, 2010		40,654
Cash dividends paid-$0.76 per share	(30,943)			(30,943)
Exercise of stock options	2,977		2,977
Exercise of stock options, Shares		485
Issuance of restricted shares, net of forfeitures		165
Cancellation of restricted shares		(85)
Conversion of restricted stock units		18
Stock compensation expense	2,504		2,504
Net Earnings	26,831			26,831
Foreign currency translation adjustment	(206)				(206)
Ending balance at Sep. 30, 2011	138,524		100,010	38,065	449
Ending balance, Shares at Sep. 30, 2011		41,237
Cash dividends paid-$0.76 per share	(31,226)			(31,226)
Exercise of stock options	446		446
Exercise of stock options, Shares		47
Issuance of restricted shares, net of forfeitures		(5)
Conversion of restricted stock units		5
Stock compensation expense	1,987		1,987
Net Earnings	33,371			33,371
Foreign currency translation adjustment	(354)				(354)
Ending balance at Sep. 30, 2012	142,748		102,443	40,210	95
Ending balance, Shares at Sep. 30, 2012		41,284
Cash dividends paid-$0.76 per share	(31,354)			(31,354)
Exercise of stock options	2,564		2,564
Exercise of stock options, Shares	225	226
Conversion of restricted stock units		8
Stock compensation expense	2,405		2,405
Net Earnings	38,032			38,032
Foreign currency translation adjustment	650				650
Ending balance at Sep. 30, 2013	$ 155,045		$ 107,412	$ 46,888	$ 745
Ending balance, Shares at Sep. 30, 2013		41,518