Accumulated Other Comprehensive Loss - Components (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ 33,802	$ 21,001
Ending Balance	30,428	33,802
Accumulated other comprehensive loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(10,825)	(10,163)
Change in period	(1,828)	(657)
Tax effect of change in period	60	(5)
Ending Balance	(12,593)	(10,825)
Effect of Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(4,346)	(3,214)
Change in period	(765)	(1,132)
Ending Balance	(5,111)	(4,346)
Minimum Pension Liability
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(6,479)	(6,949)
Change in period	(1,063)	475
Tax effect of change in period	60	(5)
Ending Balance	$ (7,482)	$ (6,479)