Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Adoption of ASU [Member]	Common Shares Issued [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Retained Earnings [Member] Adoption of ASU [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated Other Comprehensive Income (Loss) [Member] Adoption of ASU [Member]
Beginning balance at Sep. 30, 2017	$ 169,585			$ 125,608	$ 46,923		$ (2,946)
Beginning balance, Shares at Sep. 30, 2017			42,207,000
Cash dividends paid	(21,170)				(21,170)
Conversion of restricted share units and exercise of stock options	183			183
Conversion of restricted share units and exercise of stock options, Shares			193,000
Stock compensation expense	3,402			3,402
Net earnings	23,849				23,849
Foreign currency translation adjustment	(1,075)						(1,075)
Hedging activity, net of tax	644						644
Ending balance at Sep. 30, 2018	175,418			129,193	49,602		(3,377)
Ending balance, Shares at Sep. 30, 2018			42,400,000
Cash dividends paid	(10,612)				(10,612)
Conversion of restricted share units and exercise of stock options	390			390
Conversion of restricted share units and exercise of stock options, Shares			312,000
Stock compensation expense	3,251			3,251
Net earnings	24,382				24,382
Foreign currency translation adjustment	(802)						(802)
Hedging activity, net of tax	(944)						(944)
Adoption of Accounting Standard Update (ASU) | Accounting Standards Update 2014-09 [Member]		$ (116)				$ (116)
Adoption of Accounting Standard Update (ASU) | Accounting Standards Update 2018-02 [Member]						$ (148)		$ 148
Ending balance at Sep. 30, 2019	190,967			132,834	63,108		(4,975)
Ending balance, Shares at Sep. 30, 2019			42,712,000
Conversion of restricted share units and exercise of stock options	3,559			3,559
Conversion of restricted share units and exercise of stock options, Shares			357,000
Stock compensation expense	3,802			3,802
Net earnings	46,186				46,186
Foreign currency translation adjustment	3,884						3,884
Hedging activity, net of tax	(769)						(769)
Ending balance at Sep. 30, 2020	$ 247,629			$ 140,195	$ 109,294		$ (1,860)
Ending balance, Shares at Sep. 30, 2020			43,069,000