Income Taxes (Loss Carryforwards) (Details) - USD ($) $ in Millions	Apr. 30, 2023		Apr. 30, 2022
Operating Loss Carryforwards [Line Items]
Loss and Credit Carryforwards	$ 327		$ 294
Deferred Tax Assets, Loss and Credit Carryforwards	62		69
Loss and Credit Carryforwards, Valuation Allowance	(14)		(27)
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Loss and Credit Carryforwards	111		53
Deferred Tax Assets, Loss and Credit Carryforwards	20	[1]	19
Loss and Credit Carryforwards, Valuation Allowance	(6)		(8)
Domestic Tax Authority | Not Subject to Expiration [Member]
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Loss and Credit Carryforwards	10
Domestic Tax Authority | Subject to Expiration [Member]
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Loss and Credit Carryforwards	10
Foreign Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Loss and Credit Carryforwards	216		241
Deferred Tax Assets, Loss and Credit Carryforwards	42	[2]	50
Loss and Credit Carryforwards, Valuation Allowance	(8)		$ (19)
Foreign Tax Authority [Member] | Not Subject to Expiration [Member]
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Loss and Credit Carryforwards	19
Foreign Tax Authority [Member] | Subject to Expiration [Member]
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Loss and Credit Carryforwards	$ 23

[1] As of April 30, 2023, the deferred tax asset amount includes credit carryforwards of $10 that do not expire and loss and credit carryforwards of $10 that expire in varying amounts from 2023 to 2039.

[2] As of April 30, 2023, the deferred tax asset includes loss carryforwards of $19 that do not expire and $23 that expire in varying amounts over the next 10 years.