Other Financial Instruments and Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Apr. 30, 2025	Jan. 31, 2025	Apr. 30, 2025	Apr. 30, 2024	Apr. 30, 2023	Oct. 31, 2024	Nov. 15, 2023	Apr. 28, 2023
Fair Value Disclosures [Abstract]
Company's Municipal bond mature in Year One	$ 0.9		$ 0.9
Company's Municipal bond mature in Year Two	3.9		3.9
Company's Municipal bond mature in Year Three	0.4		0.4
Company's Municipal bond mature in Year Four	3.3		3.3
Company's Municipal bond mature in Year Five	0.9		0.9
Company's Municipal bond mature in Year Six and beyond	6.4		6.4
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Realized Investment Gains (Losses)			0.0	$ (21.5)	$ 0.0
Other intangible assets impairment charges	112.7	$ 208.2	320.9	$ 0.0	0.0
Voortman
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Disposal Group, Including Discontinued Operation, Goodwill						$ 251.0
Voortman
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Disposal Group, Including Discontinued Operation, Goodwill	251.1		251.1
Sweet Baked Snacks Value Brands
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Disposal Group, Including Discontinued Operation, Goodwill	26.6		26.6
Post Holdings Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in equity securities, current, ownership percentage				8.00%
Cumulative realized loss on investment in equity securities - net				$ 30.7
Realized Investment Gains (Losses)				26.9	3.8
Post Holdings Inc. | Pet Food Brands
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in equity securities					$ 487.8		$ 460.9	$ 491.6
U.S. Retail Frozen Handheld and Spreads | Sahale Snacks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Disposal Group, Including Discontinued Operation, Goodwill	$ 11.5		$ 11.5
U.S. Retail Pet Foods | Pet Food Brands
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Disposal Group, Including Discontinued Operation, Goodwill				$ 790.3