Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Additional Paid-in Capital	Additional Paid-in Capital Cumulative Effect, Period of Adoption, Adjustment	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Loss
Beginning balance (in shares) at Sep. 30, 2019			55,535
Beginning balance at Sep. 30, 2019	$ 744,949		$ 556	$ 407,628		$ 389,163		$ (52,398)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock compensation	(5,094)			(5,094)
Release of restricted stock (in shares)			711
Release of restricted stock	6		$ 6
Taxes paid related to net share settlement of equity awards	(1,435)			(1,435)
Foreign currency translation adjustment, net of tax	(15,678)					(8)		(15,670)
Purchase and retirement of treasury shares (in shares)			(943)
Purchase and retirement of treasury stock	(5,158)		$ (11)	(2,624)		(2,523)
Net income (loss)	(68,463)					(68,463)
Ending balance (in shares) at Sep. 30, 2020			55,303
Ending balance at Sep. 30, 2020	649,127		$ 551	398,475		318,169		(68,068)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock compensation	3,946			3,946
Release of restricted stock (in shares)			508
Release of restricted stock	7		$ 7
Transfer of consideration for current period acquisition (in shares)			213
Transfer of consideration for current period acquisition	1,547		$ 2	1,545
Transfer of consideration for prior period acquisition (in shares)			33
Transfer of consideration for prior period acquisition	185			185
Taxes paid related to net share settlement of equity awards	(839)			(839)
Foreign currency translation adjustment, net of tax	9,653							9,653
Net income (loss)	8,612					8,612
Ending balance (in shares) at Sep. 30, 2021			56,057
Ending balance at Sep. 30, 2021	$ 672,238	$ (36,638)	$ 560	403,312	$ (62,804)	326,781	$ 26,166	(58,415)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accounting Standards Update [Extensible Enumeration]	Accounting Standards Update 2020-06
Stock compensation	$ 5,053			5,053
Release of restricted stock (in shares)			393
Release of restricted stock	4		$ 4
Transfer of consideration for other investment (in shares)			213
Transfer of consideration for other investment	1,500		$ 2	1,498
Taxes paid related to net share settlement of equity awards	(792)			(792)
Foreign currency translation adjustment, net of tax	2,746							2,746
Purchase and retirement of treasury shares (in shares)			(238)
Purchase and retirement of treasury stock	(2,040)		$ (2)	(937)		(1,101)
Net income (loss)	50,160					50,160
Ending balance (in shares) at Sep. 30, 2022			56,425
Ending balance at Sep. 30, 2022	$ 692,231		$ 564	$ 345,330		$ 402,006		$ (55,669)