Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive loss	$ 45,981	$ 49,622	$ 49,141	$ 45,523
Foreign currency translation adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive loss	(5,476)	(5,359)
Retirement plan liability adjustment, net of tax
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive loss	(3,601)	(3,720)
Other
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive loss	(6)	0
Total accumulated other comprehensive loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive loss	$ (9,083)	$ (9,079)	$ (12,970)	$ (13,468)