Income Taxes - Components of Deferred Income Tax Assets (Liabilities) (Details) - USD ($) $ in Millions	Apr. 30, 2026	Apr. 30, 2025	Apr. 30, 2024	Apr. 30, 2023
Deferred tax assets:
Lease liabilities	$ 738.0	$ 696.0
Accruals and reserves	196.0	172.0
Net operating loss and credit carryforwards	29.0	28.0
Capital loss carryforwards	15.0	15.0
Interest carryforwards	0.0	1.0
Other deferred tax assets	5.0	0.0
Gross deferred tax assets	983.0	912.0
Valuation allowances	(24.0)	(18.0)	$ (13.0)	$ (27.0)
Total net deferred tax assets	959.0	894.0
Deferred tax liabilities:
Property and equipment	(2,502.0)	(2,400.0)
Right of use assets	(680.0)	(644.0)
Intangibles	(152.0)	(131.0)
Other deferred tax liabilities	(19.0)	(7.0)
Gross deferred tax liabilities	(3,353.0)	(3,182.0)
Net deferred tax liabilities	$ (2,394.0)	$ (2,288.0)

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