Derivatives and Hedging - Financial Statement Impact of Derivatives (Details) $ in Thousands	3 Months Ended
Oct. 31, 2019 USD ($)
Designated as Hedging Instrument
Gain Loss on Derivatives Not Designated as Hedging Instruments [Abstract]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Parent	$ (3,722)
Foreign currency forward contracts \| Designated as Hedging Instrument
Gain Loss on Derivatives Not Designated as Hedging Instruments [Abstract]
Amount of gain (loss) recognized in income	(525)
Interest rate swap agreements \| Designated as Hedging Instrument
Gain Loss on Derivatives Not Designated as Hedging Instruments [Abstract]
Amount of gain (loss) recognized in income	(3,197)
Interest Expense \| Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net [Abstract]
Gain (Loss) recognized in Other Comprehensive Income, net of tax	(570)
Interest Expense \| Foreign currency forward contracts \| Cash Flow Hedging
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net [Abstract]
Gain (Loss) reclassified from AOCI, Net of Tax	0
Interest Expense \| Foreign currency forward contracts \| Designated as Hedging Instrument
Gain Loss on Derivatives Not Designated as Hedging Instruments [Abstract]
Amount of gain (loss) recognized in income	0
Interest Expense \| Interest rate swap agreements \| Cash Flow Hedging
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net [Abstract]
Gain (Loss) reclassified from AOCI, Net of Tax	(495)
Interest Expense \| Interest rate swap agreements \| Designated as Hedging Instrument
Gain Loss on Derivatives Not Designated as Hedging Instruments [Abstract]
Amount of gain (loss) recognized in income	$ (75)

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

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- Definition

Amount, after tax and reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness, attributable to parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e637-108580

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Amount, after tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e689-108580

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e637-108580

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=109978405&loc=d3e80720-113993

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