Commitments and Contingencies - Insurance Proceeds Impact on Consolidated Condensed Statements of Operation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Loss Contingencies [Line Items]
Gain on insurance proceeds received	$ 0	$ (1,000)	$ (2,495)	$ (1,000)
Cost of goods sold	22,123	24,260	43,278	47,143
Income (loss) before income tax (benefit) expense	$ (1,326)	$ 3,221	762	1,785
Balance without insurance proceeds
Loss Contingencies [Line Items]
Cost of goods sold, balance without insurance proceeds			43,882	49,430
Gain on insurance proceeds received			0	0
Income (loss) before income tax (benefit) expense, balance without insurance proceeds			(2,337)	(1,502)
Insurance recoveries
Loss Contingencies [Line Items]
Gain on insurance proceeds received			(2,495)	(1,000)
Insurance recoveries | Cost of goods sold
Loss Contingencies [Line Items]
Gain on insurance proceeds received			(604)	(2,287)
Insurance recoveries | Income (loss) before income tax (benefit) expense
Loss Contingencies [Line Items]
Gain on insurance proceeds received			$ (3,099)	$ (3,287)