Stock Repurchases (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Oct. 31, 2020	Apr. 30, 2020	Oct. 31, 2019
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Options Exercised	771,000
Weighted Average Exercise Price	$ 25.97
Employee Stock-Based Tax Withholding (in 000s)			$ 101,300
Chief Executive Officer [Member] | Common Stock
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Options Exercised		4,000,000
Weighted Average Exercise Price			$ 17.81
Shares Net Settled for Exercise			865,719
Shares Withheld for Taxes(1)			1,231,595
Net Shares to Employees			1,902,686
Weighted Average Share Price for Withholding			$ 82.29
Employee Stock-Based Tax Withholding (in 000s)			$ 101,348