Retirement and Postemployment Benefits (Schedule of Components of net periodic benefit (income) expense) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Feb. 27, 2022	Feb. 28, 2021	Feb. 27, 2022	Feb. 28, 2021
Defined Benefit Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 23.2	$ 26.1	$ 70.4	$ 78.1
Interest cost	46.0	48.0	138.4	143.9
Expected return on plan assets	(102.8)	(105.3)	(308.5)	(315.4)
Amortization of losses (gains)	35.7	27.1	106.1	81.1
Amortization of prior service costs (credits)	0.2	0.3	0.6	0.9
Other adjustments	0.0	0.0	0.0	0.0
Curtailment loss			(14.3)	0.0
Net expense (income)	2.3	(3.8)	(7.3)	(11.4)
Other Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	2.0	2.0	5.8	6.3
Interest cost	3.1	4.5	9.4	13.5
Expected return on plan assets	(6.6)	(8.7)	(20.0)	(26.0)
Amortization of losses (gains)	(2.7)	(1.3)	(8.1)	(3.8)
Amortization of prior service costs (credits)	(5.3)	(1.3)	(15.7)	(4.1)
Other adjustments	0.0	0.0	0.0	0.0
Curtailment loss			(5.7)	0.0
Net expense (income)	(9.5)	(4.8)	(34.3)	(14.1)
Postemployment Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1.8	2.3	5.3	6.9
Interest cost	0.4	0.4	1.1	1.2
Expected return on plan assets	0.0	0.0	0.0	0.0
Amortization of losses (gains)	0.8	0.7	2.3	2.1
Amortization of prior service costs (credits)	0.1	0.1	0.3	0.5
Other adjustments	4.0	2.1	9.7	6.5
Curtailment loss			0.0	0.0
Net expense (income)	$ 7.1	$ 5.6	$ 18.7	$ 17.2