Commitments and Contingencies - Insurance Proceeds Impact On Consolidated Condensed Statements Of Operation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Loss Contingencies [Line Items]
Cost of goods sold, balance without insurance proceeds	$ 25,377		$ 49,430
Gain on insurance proceeds received	(1,000)	$ (1,164)	(1,000)	$ (1,164)
Cost of goods sold	24,260	25,304	47,143	51,633
Net loss, balance without insurance proceeds	1,143		(1,368)
Net income (loss)	3,260	$ (1,258)	1,919	$ (2,540)
Cost of goods sold
Loss Contingencies [Line Items]
Gain on insurance proceeds received	(1,117)		(2,287)
Net income (loss)
Loss Contingencies [Line Items]
Gain on insurance proceeds received	$ (2,117)		$ (3,287)