Long-term Obligations - Minimum Lease Rental Payments (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Sep. 30, 2019
Long-term obligations (less current portion)
Finance lease rental payments	$ 7,853	$ 7,979
Environmental post-closure monitoring and maintenance activities	606	606
Long-term disability	256	251
Deferred dividends	165	40
Less amounts due within one year	(307)	(267)
Long-term obligations (less current portion)	$ 8,573	$ 8,609

Total costs accrued as of the balance sheet date for environmental loss contingencies.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant