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Derivatives and Hedging - Additional Information (Detail) £ in Thousands, $ in Thousands, € in Millions	3 Months Ended	9 Months Ended
	Apr. 30, 2019 USD ($)	Apr. 30, 2019 USD ($)	Apr. 30, 2019 GBP (£)	Sep. 18, 2018 EUR (€)
Foreign currency transaction	$ 7,379	$ 7,379
Amount reclassified	0	0
Not Designated as Hedging Instrument
Reclassified out of AOCI	0	0
Acquisition Costs \| Foreign Currency Contract Losses
Acquisition related costs	70,777
Interest Rate Swap \| Designated as Hedging Instrument
Notional Amount	900,000	900,000
Foreign Exchange Forward
Notional Amount \| £			£ 25,000
Income related to contract	$ 2,930
Acquisition related costs		$ 70,777
Foreign Exchange Forward \| Not Designated as Hedging Instrument
Notional Amount \| €				€ 1,625