Fair Value Measurements (Details) - USD ($)	3 Months Ended
Oct. 31, 2020	Jul. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Notional amounts	$ 125,100,000	$ 82,000,000.0
Interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Notional amounts	40,000,000.0	0
Interest rate swap \| Cash Flow Hedge
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Notional amounts	$ 40,000,000.0
Maximum length of time hedged in interest rate ( in years)	10 years
Fair Value, Inputs, Level 2 \| Fair Value \| Fixed Interest Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt instrument, fair value disclosure	$ 295,700,000	297,300,000
Fair Value, Inputs, Level 2 \| Fair Value \| Variable Interest Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt instrument, fair value disclosure	308,700,000	350,000,000.0
Fair Value, Inputs, Level 2 \| Carrying Value \| Fixed Interest Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt instrument, fair value disclosure	275,000,000.0	275,000,000.0
Fair Value, Inputs, Level 2 \| Carrying Value \| Variable Interest Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt instrument, fair value disclosure	308,700,000	350,000,000.0
Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Equity method investments	$ 22,300,000	$ 21,700,000

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

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Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8813-108599

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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+ References

No definition available.

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Maximum period the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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