Leases - average lease terms and discount rates (Details)	Aug. 31, 2022	Aug. 31, 2021
Weighted average remaining lease term in years
Operating leases	10 years	10 years 3 months 18 days
Finance leases	19 years	20 years 2 months 12 days
Weighted average discount rate
Operating leases	4.83%	4.77%
Finance leases	5.19%	5.18%

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

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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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)
-URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980

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-Publisher FASB
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-Section 55
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-URI https://asc.fasb.org/extlink&oid=123414884&loc=SL77918982-209971

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

+ References

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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 https://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 https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980

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Leases, Weighted Average Discount Rate

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