Stock Based Compensation And Stockholders Equity [Line Items]

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Amount of noncash expense for share-based payment arrangement.

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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Percentage of vesting of award under share-based payment arrangement.

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STOCKHOLDERS' EQUITY - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2018
Stock Based Compensation And Stockholders Equity [Line Items]
Total compensation expenses	$ 19,889	$ 18,950	$ 17,000
Total unrecognized compensation costs	$ 18,219
Period for recognition of compensation cost not yet recognized	1 year 7 months 2 days
Tax benefits from stock compensation expense	$ 4,775	4,550	4,930
2010 Equity Incentive Plan
Stock Based Compensation And Stockholders Equity [Line Items]
Number of shares available to be granted	1,211,385
2016 Equity Incentive Plan
Stock Based Compensation And Stockholders Equity [Line Items]
Number of shares authorized under stock option plan	2,000,000
Number of shares available to be granted	982,258
Performance Shares (PSUs) \| Share-based Payment Arrangement, Tranche One
Stock Based Compensation And Stockholders Equity [Line Items]
Award vesting rights, minimum percentage of target compensation	50.00%
Performance Shares (PSUs) \| Share-based Payment Arrangement, Tranche Three
Stock Based Compensation And Stockholders Equity [Line Items]
Award vesting rights, minimum percentage of target compensation	150.00%
Performance Shares (PSUs) \| Minimum \| Share-based Payment Arrangement, Tranche Two
Stock Based Compensation And Stockholders Equity [Line Items]
Award vesting rights, minimum percentage of target compensation	50.00%
Performance Shares (PSUs) \| Maximum \| Share-based Payment Arrangement, Tranche Two
Stock Based Compensation And Stockholders Equity [Line Items]
Award vesting rights, minimum percentage of target compensation	150.00%
Restricted Stock Units (RSUs)
Stock Based Compensation And Stockholders Equity [Line Items]
Total compensation expenses	$ 19,889	$ 18,950	$ 17,000