Income Taxes (Earnings of Foreign Subsidiaries) (Details) - USD ($) $ in Millions	12 Months Ended
Apr. 30, 2020	Apr. 30, 2019
Income Tax Disclosure [Abstract]
Undistributed Earnings of Foreign Subsidiaries	$ 1,279	$ 1,266
Foreign Earnings Repatriated	15	$ 120
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount	$ 1

Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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