Long-term Obligations - Minimum Lease Rental Payments (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017
Future minimum lease rental payments
2019	$ 989
2020	994
2021	1,001
2022	1,012
2023	1,024
Thereafter	12,572
Total minimum lease payments	17,592
Less amounts representing interest	(9,466)
Present value of net minimum lease payments	8,126
Less current obligation	(147)	$ (926)
Total long term lease obligation	7,979
Long-term obligations (less current portion)
Capital lease rental payments	4,207	4,275
Finance lease rental payments	3,920	4,017
Environmental post-closure monitoring and maintenance activities	504	633
Deferred dividends	14
Less amounts due within one year	(202)	(1,029)
Long-term obligations (less current portion)	$ 8,443	$ 7,896

Represents the amount of accrued deferred dividends.

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Present value of minimum lease payments for capital leases (excluding finance leases) net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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Represents the current portion accrued as of the balance sheet date of both the total costs for environmental loss contingencies and the present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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Represents the noncurrent portion accrued as of the balance sheet date of both the total costs for environmental loss contingencies and the present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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Present value of minimum lease payments for finance leases included in capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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

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Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date.

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Amount of minimum lease payments for capital leases.

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Amount of minimum lease payments for capital leases due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount necessary to reduce net minimum lease payments to present value for capital leases.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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