Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Treasury Stock, Common	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive (Loss) Income
Beginning balance (in shares) at Sep. 30, 2022		41,950	6,413
Beginning balance at Sep. 30, 2022	$ 501,513	$ 420	$ (58,172)	$ 385,244	$ 200,075	$ (26,054)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	5,779				5,779
Other comprehensive (loss) income	1,289					1,289
Employee stock purchase plan issuances (in shares)			(20)
Employee stock purchase plan issuances	594		$ 186	408
Taxes paid for net share settlement of share-based payment awards (in shares)			72
Taxes paid for net share settlement of share-based payment awards	(2,987)		$ (2,987)
Issuance of stock under stock award plans (in shares)		249
Issuance of stock under stock award plans	872	$ 2		870
Stock-based compensation expense	2,868			2,868
Ending balance (in shares) at Dec. 31, 2022		42,199	6,465
Ending balance at Dec. 31, 2022	509,928	$ 422	$ (60,973)	389,390	205,854	(24,765)
Beginning balance (in shares) at Sep. 30, 2023		42,501	6,436
Beginning balance at Sep. 30, 2023	540,488	$ 425	$ (61,506)	403,735	224,845	(27,011)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	(3,054)				(3,054)
Other comprehensive (loss) income	2,948					2,948
Employee stock purchase plan issuances (in shares)			(24)
Employee stock purchase plan issuances	531		$ 231	300
Taxes paid for net share settlement of share-based payment awards (in shares)			88
Taxes paid for net share settlement of share-based payment awards	(2,168)		$ (2,135)	(33)
Issuance of stock under stock award plans (in shares)		248
Issuance of stock under stock award plans	224	$ 2		222
Stock-based compensation expense	3,106			3,106
Ending balance (in shares) at Dec. 31, 2023		42,749	6,500
Ending balance at Dec. 31, 2023	$ 542,075	$ 427	$ (63,410)	$ 407,330	$ 221,791	$ (24,063)