Stockholder's Equity (Details Textuals) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended	118 Months Ended
Jul. 31, 2021	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payments for Employee Stock-Based Tax Withholdings	$ 6,145	$ 103,451	$ 46,888
Stockholders' Equity, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock, shares authorized	400,000,000	400,000,000		400,000,000
Common stock par value (in dollars per share)	$ 0.0001	$ 0.0001		$ 0.0001
Common stock, shares outstanding	237,014,273	235,315,337		237,014,273
Common stock, reserved for issuance of stock options	15,326,030	12,977,173		15,326,030
Common stock, shares issued	237,014,273	235,315,337		237,014,273
Preferred Stock, Shares Authorized	5,000,000	5,000,000		5,000,000
Preferred Stock, Shares Outstanding	0	0		0
Preferred Stock, Shares Issued	0	0		0
Employee Stock Purchase Plan
Stockholders' Equity, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock, reserved for issuance of stock options	1,194,213	1,303,592		1,194,213
Stock Repurchase Program 2011 [Member]
Stockholders' Equity, Number of Shares, Par Value and Other Disclosures [Abstract]
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased	81,450,802			81,450,802
Stock Repurchased and Retired During Period, Shares			7,635,596	114,549,198
Settlement with Taxing Authority [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payments for Employee Stock-Based Tax Withholdings	$ 3,800	$ 101,300	$ 45,600

Aggregate number of common shares reserved for future issuance.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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Number of shares that have been repurchased and retired during the period.

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