Pension and Retirement Plans - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
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
U.S. \| Pension
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Loans, Gross, Insurance Policy	$ 2.4	$ 2.2

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.

+ Details

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(e))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(a)(7))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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