Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive (Loss) Income
Beginning balance (in shares) at Sep. 30, 2021		40,653	6,391
Beginning balance at Sep. 30, 2021	$ 472,517	$ 407	$ (56,535)	$ 370,699	$ 180,692	$ (22,746)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,187				1,187
Other comprehensive (loss) income	(212)					(212)
Employee stock purchase plan issuances (in shares)			(18)
Employee stock purchase plan issuances	321		$ 161	160
Taxes paid for net share settlement of share-based payment awards (in shares)			74
Taxes paid for net share settlement of share-based payment awards	(6,025)		$ (1,726)	(4,299)
Issuance of stock under stock award plans (in shares)		760
Issuance of stock under stock award plans	4,227	$ 7		4,220
Stock-based compensation expense	2,017			2,017
Ending balance (in shares) at Dec. 31, 2021		41,413	6,447
Ending balance at Dec. 31, 2021	474,032	$ 414	$ (58,100)	372,797	181,879	(22,958)
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)