Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Shares Issued [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning balance at Sep. 30, 2016	$ 166,472		$ 122,356	$ 49,632	$ (5,516)
Beginning balance, Shares at Sep. 30, 2016		42,107,000
Cash dividends paid	(24,266)			(24,266)
Conversion of restricted share units and exercise of stock options	(129)		(129)
Conversion of restricted share units and exercise of stock options, Shares		100,000
Stock compensation expense	3,381		3,381
Net earnings	21,557			21,557
Foreign currency translation adjustment	1,616				1,616
Hedging activity, net of tax	954				954
Ending balance at Sep. 30, 2017	169,585		125,608	46,923	(2,946)
Ending 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 ASU | Accounting Standards Update 2014-09 [Member]	(116)			(116)
Adoption of 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