Pension and Retirement Plans - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022
Pension and Retirement Plans
Number of Years Defined Benefit Plans are Closed to Newly Hired Employees	2 years
Number of Years Supplementary Retirement Plans are Closed to Newly Hired Employees	2 years
Life insurance amount due	$ 1,349	$ 1,447
Proceeds from corporate life insurance owned policy	0	322
Pension:
Pension and Retirement Plans
Gain on a life insurance policy	(321)	(4,595)
UNITED STATES
Pension and Retirement Plans
Life insurance amount due	1,349	1,447
UNITED STATES \| Pension:
Pension and Retirement Plans
Loans, Gross, Insurance Policy	3,700	3,500
Gain on a life insurance policy	(4)	(21)
Life insurance amount due	$ 202	$ 261

Number of years that all of the Company's defined benefit plans are closed to newly hired employees.

No definition available.

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- Definition

Number of years that the Company's supplementary retirement plans are closed to newly hired employees.

+ References

No definition available.

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- Definition

Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(4)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount before allowance of loans made to policy and contract holders using their life insurance contracts' cash value or separate accounts as collateral. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums over and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1)(e))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

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- Definition

Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(15))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

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-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
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-Section 45
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-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

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- Definition

Amount of cash inflow for proceeds from settlement of corporate-owned life insurance policy, classified as investing activities. Includes, but is not limited to, bank-owned life insurance policy.

+ References

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