Derivatives	3 Months Ended
Oct. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	Derivatives In order to hedge against the impact of fluctuations in the value of the Euro, British Pound, Canadian dollar, Australian dollar and Singapore dollar relative to the U.S. dollar on the conversion of such net assets into the functional currencies, we enter into short-term forward contracts to purchase Euros, British Pounds, Canadian dollars, Australian dollars and Singapore dollars, which contracts are one-month in duration. These short-term contracts are designated as fair value hedge instruments. These foreign currency forward contracts are continually replaced with new one-month contracts as long as we have significant net assets that are denominated and ultimately settled in currencies other than each entity’s functional currency. Gains and losses related to hedging contracts to buy Euros, British Pounds, Canadian dollars, Australian dollars and Singapore dollars forward are immediately realized within general and administrative expenses due to the short-term nature of such contracts. We do not currently hedge against the impact of fluctuations in the value of the Chinese Renminbi relative to the U.S. dollar because the overall foreign currency exposures relating to those currencies are currently not deemed significant. There were seven foreign currency forward contracts with an aggregate notional value of $23,077 and $24,762 at October 31, 2017 and July 31, 2017, respectively, which covered certain assets and liabilities that were denominated in currencies other than each entity’s functional currency. For the three months ended October 31, 2017 and 2016, our forward contracts resulted in an immaterial amount of net currency conversion losses, net of tax, on the hedged items.

Derivatives

In order to hedge against the impact of fluctuations in the value of the Euro, British Pound, Canadian dollar, Australian dollar and Singapore dollar relative to the U.S. dollar on the conversion of such net assets into the functional currencies, we enter into short-term forward contracts to purchase Euros, British Pounds, Canadian dollars, Australian dollars and Singapore dollars, which contracts are one-month in duration. These short-term contracts are designated as fair value hedge instruments. These foreign currency forward contracts are continually replaced with new one-month contracts as long as we have significant net assets that are denominated and ultimately settled in currencies other than each entity’s functional currency. Gains and losses related to hedging contracts to buy Euros, British Pounds, Canadian dollars, Australian dollars and Singapore dollars forward are immediately realized within general and administrative expenses due to the short-term nature of such contracts. We do not currently hedge against the impact of fluctuations in the value of the Chinese Renminbi relative to the U.S. dollar because the overall foreign currency exposures relating to those currencies are currently not deemed significant.

There were seven foreign currency forward contracts with an aggregate notional value of $23,077 and $24,762 at October 31, 2017 and July 31, 2017, respectively, which covered certain assets and liabilities that were denominated in currencies other than each entity’s functional currency. For the three months ended October 31, 2017 and 2016, our forward contracts resulted in an immaterial amount of net currency conversion losses, net of tax, on the hedged items.