Leases (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Feb. 27, 2021	Feb. 29, 2020	Feb. 27, 2021	Feb. 29, 2020	May 30, 2020
Leases [Abstract]
Operating lease costs	$ 13.3	$ 13.1	$ 36.8	$ 38.5
Short-term lease costs	0.9	0.7	2.4	1.9
Variable lease costs*	2.3	2.1	5.9	6.5
Total	16.5	15.9	45.1	46.9
Supply Arrangement Variable Lease Costs	22.8	18.6	61.4	64.3
2021	13.1		13.1
2022	50.7		50.7
2023	48.2		48.2
2024	42.9		42.9
2025	37.9		37.9
Thereafter	105.1		105.1
Total lease payments*	297.9		297.9
Less interest	29.1		29.1
Present value of lease liabilities	268.8		268.8
Leases Not yet Commenced Future Payments	17.3		17.3
Lease liabilities, noncurrent	$ 200.6		$ 200.6		$ 178.8
Weighted Average Remaining Lease Term	7 years		7 years
Weighted Average Discount Rate, Percent	2.80%		2.80%
Operating cash flows used for operating leases	$ 13.5	12.5	$ 36.3	38.4
Right-of-use assets obtained in exchange for new liabilities	$ 7.1	$ 0.3	$ 55.7	$ 9.1

Legally binding future minimum lease payments for lessee's operating lease that has not yet commenced.

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- Definition

Amount of variable leases costs, excluded from lease liability, related to raw meterial purchases under certain supply arrangements that the Company has determined to meet the definition of a lease.

+ References

No definition available.

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- Definition

Amount of lease cost recognized by lessee for lease contract.

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease having initial or remaining lease term in excess of one year to be paid in remainder of current fiscal year.

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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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