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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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Amount of cash outflow to satisfy grantee's tax withholding obligation for award under share-based payment arrangement.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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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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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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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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No definition available.

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

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Stockholder's Equity (Details Textuals) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended			12 Months Ended			94 Months Ended
	Apr. 30, 2019	Jan. 31, 2019	Oct. 31, 2017	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payments for Employee Stock-Based Tax Withholdings	$ 45,565	$ 0	$ 134,615	$ 46,888	$ 1,115	$ 135,433
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				229,790,268	233,898,841		229,790,268
Common stock, reserved for issuance of stock options				20,502,335	25,621,327		20,502,335
Common stock, shares issued				229,790,268	233,898,841		229,790,268
Preferred stock, shares authorized				5,000,000,000,000	5,000,000		5,000,000,000,000
Preferred stock par value (in dollars per share)				$ 0.0001	$ 0.0001		$ 0.0001
Preferred stock, shares issued				0	0		0
Preferred stock, shares outstanding				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				1,426,698	1,603,741		1,426,698
Stock Repurchase Program 2011 [Member]
Stockholders' Equity, Number of Shares, Par Value and Other Disclosures [Abstract]
Stock Repurchased and Retired During Period, Shares				7,635,596			114,549,198
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased				81,450,802			81,450,802
Settlement with Taxing Authority [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payments for Employee Stock-Based Tax Withholdings				$ 45,600	$ 0	$ 134,600