Other Financial Instruments and Fair Value Measurements (Details 1) - Fair value measurements recurring [Member] - USD ($) $ in Millions		Apr. 30, 2024	Apr. 30, 2023
Financial assets (liabilities) measured at fair value on a recurring basis
Investment in equity securities	[1]		$ 487.8
Total long-term debt	[2]	$ (7,652.9)	(3,879.1)
Total financial instruments measured at fair value		(7,602.6)	(3,362.6)
Equity mutual funds [Member]
Financial assets (liabilities) measured at fair value on a recurring basis
Marketable securities and other investments	[3]	4.5	5.0
Municipal obligations [Member]
Financial assets (liabilities) measured at fair value on a recurring basis
Marketable securities and other investments	[3]	17.2	18.6
Money Market Funds [Member]
Financial assets (liabilities) measured at fair value on a recurring basis
Marketable securities and other investments	[3]	0.4	0.4
Commodity contracts - net
Financial assets (liabilities) measured at fair value on a recurring basis
Derivative financial instruments	[4]	26.4	3.4
Foreign currency exchange contracts - net
Financial assets (liabilities) measured at fair value on a recurring basis
Derivative financial instruments	[4]	1.8	1.3
Fair Value, Inputs, Level 1 [Member]
Financial assets (liabilities) measured at fair value on a recurring basis
Investment in equity securities	[1]		487.8
Total long-term debt	[2]	(7,652.9)	(3,879.1)
Total financial instruments measured at fair value		(7,620.8)	(3,383.0)
Fair Value, Inputs, Level 1 [Member] | Equity mutual funds [Member]
Financial assets (liabilities) measured at fair value on a recurring basis
Marketable securities and other investments	[3]	4.5	5.0
Fair Value, Inputs, Level 1 [Member] | Municipal obligations [Member]
Financial assets (liabilities) measured at fair value on a recurring basis
Marketable securities and other investments	[3]	0.0	0.0
Fair Value, Inputs, Level 1 [Member] | Money Market Funds [Member]
Financial assets (liabilities) measured at fair value on a recurring basis
Marketable securities and other investments	[3]	0.4	0.4
Fair Value, Inputs, Level 1 [Member] | Commodity contracts - net
Financial assets (liabilities) measured at fair value on a recurring basis
Derivative financial instruments	[4]	26.7	2.7
Fair Value, Inputs, Level 1 [Member] | Foreign currency exchange contracts - net
Financial assets (liabilities) measured at fair value on a recurring basis
Derivative financial instruments	[4]	0.5	0.2
Fair Value, Inputs, Level 2 [Member]
Financial assets (liabilities) measured at fair value on a recurring basis
Investment in equity securities	[1]		0.0
Total long-term debt	[2]	0.0	0.0
Total financial instruments measured at fair value		18.2	20.4
Fair Value, Inputs, Level 2 [Member] | Equity mutual funds [Member]
Financial assets (liabilities) measured at fair value on a recurring basis
Marketable securities and other investments	[3]	0.0	0.0
Fair Value, Inputs, Level 2 [Member] | Municipal obligations [Member]
Financial assets (liabilities) measured at fair value on a recurring basis
Marketable securities and other investments	[3]	17.2	18.6
Fair Value, Inputs, Level 2 [Member] | Money Market Funds [Member]
Financial assets (liabilities) measured at fair value on a recurring basis
Marketable securities and other investments	[3]	0.0	0.0
Fair Value, Inputs, Level 2 [Member] | Commodity contracts - net
Financial assets (liabilities) measured at fair value on a recurring basis
Derivative financial instruments	[4]	(0.3)	0.7
Fair Value, Inputs, Level 2 [Member] | Foreign currency exchange contracts - net
Financial assets (liabilities) measured at fair value on a recurring basis
Derivative financial instruments	[4]	1.3	1.1
Fair Value, Inputs, Level 3 [Member]
Financial assets (liabilities) measured at fair value on a recurring basis
Investment in equity securities	[1]		0.0
Total long-term debt	[2]	0.0	0.0
Total financial instruments measured at fair value		0.0	0.0
Fair Value, Inputs, Level 3 [Member] | Equity mutual funds [Member]
Financial assets (liabilities) measured at fair value on a recurring basis
Marketable securities and other investments	[3]	0.0	0.0
Fair Value, Inputs, Level 3 [Member] | Municipal obligations [Member]
Financial assets (liabilities) measured at fair value on a recurring basis
Marketable securities and other investments	[3]	0.0	0.0
Fair Value, Inputs, Level 3 [Member] | Money Market Funds [Member]
Financial assets (liabilities) measured at fair value on a recurring basis
Marketable securities and other investments	[3]	0.0	0.0
Fair Value, Inputs, Level 3 [Member] | Commodity contracts - net
Financial assets (liabilities) measured at fair value on a recurring basis
Derivative financial instruments	[4]	0.0	0.0
Fair Value, Inputs, Level 3 [Member] | Foreign currency exchange contracts - net
Financial assets (liabilities) measured at fair value on a recurring basis
Derivative financial instruments	[4]	$ 0.0	$ 0.0

[1] The market approach is utilized to measure the fair value of equity securities. The investment in equity securities represented our equity interest in Post of approximately 8 percent as of April 30, 2023, which was valued using the trading value of Post common stock. The investment in equity securities was valued at $460.9 on the settlement date. As a result, we recognized a realized pre-tax loss of $30.7 on the investment, of which $26.9 and $3.8 was recognized during 2024 and 2023, respectively, and was included in other income (expense) – net in the Statements of Consolidated Income. For additional information, see Investment in Equity Securities in Note 1: Accounting Policies and Note 3: Divestitures.

[2] Long-term debt is composed of public Senior Notes, which are traded in an active secondary market and valued using quoted prices. For additional information, see Note 8: Debt and Financing Arrangements.

[3] Marketable securities and other investments consist of funds maintained for the payment of benefits associated with nonqualified retirement plans. The funds include equity securities listed in active markets, municipal obligations valued by a third-party using valuation techniques that utilize inputs that are derived principally from or corroborated by observable market data, and money market funds with maturities of three months or less. Based on the short-term nature of these money market funds, carrying value approximates fair value. As of April 30, 2024, our municipal obligations are scheduled to mature as follows: $1.5 in 2025, $0.8 in 2026, $3.8 in 2027, $0.4 in 2028, $3.4 in 2029, and the remaining $7.3 in 2030 and beyond. For additional information, see Marketable Securities and Other Investments in Note 1: Accounting Policies.

[4] Level 1 commodity and foreign currency exchange derivatives are valued using quoted market prices for identical instruments in active markets. Level 2 commodity and foreign currency exchange derivatives are valued using quoted prices for similar assets or liabilities in active markets. For additional information, see Note 10: Derivative Financial Instruments.