Leases - Supplemental Balance Sheet (Details)	Sep. 30, 2021	Sep. 30, 2020
Weighted average remaining lease term:
Operating leases	6 years 9 months 18 days	6 years 3 months 18 days
Finance leases	4 years 3 months 18 days	7 years 9 months 18 days
Weighted average discount rate:
Operating leases	1.79%	1.84%
Finance leases	3.96%	3.50%

Weighted Average Discount Rate

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- Definition

Weighted Average Remaining Lease Term

+ References

No definition available.

+ Details

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- Definition

Weighted average discount rate for finance lease calculated at point in time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
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- Definition

Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(3)
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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted average discount rate for operating lease calculated at point in time.

+ References

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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=123414884&loc=SL77918982-209971

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(3)
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918686-209980

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