Defined Benefit Plan, Recognized Net Actuarial Gain (Loss)

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Defined benefit plan recognized net actuarial gain loss percentage.

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Fair value investments ability to impose customary redemption gates.

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Fair value investments impose customary redemption gates.

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- Definition

Green zone multiemployer plan funded percentage.

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Multiemployer Plans, Withdrawal Costs

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Percentage providing more than plans total contribution.

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Red zone multiemployer plans funded percentage.

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Unfunded commitment for additional investment.

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Yellow zone multiemployer plans funded percentage.

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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- Definition

Amount of (increase) decrease in accumulated benefit obligation of defined benefit plan from effects of settlement and curtailment.

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

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Amount of (increase) decrease in benefit obligation of defined benefit plan from event reducing expected years of future service of present employees or eliminating accrual of benefits for some or all future services of present employees.

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- Definition

Amount of contributions expected to be received by defined benefit plan from employer in fiscal year. Excludes contributions paid by employer in current fiscal year.

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from event reducing expected years of future service of present employees or eliminating accrual of defined benefits for some or all future services of present employees.

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Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

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Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of cost for defined contribution plan.

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- Definition

Amount, before tax, of increase (decrease) to other comprehensive income from settlement and curtailment gain (loss) of defined benefit plan.

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PENSION AND POSTRETIREMENT BENEFITS - Narrative (Details) - USD ($) $ in Millions		3 Months Ended			12 Months Ended
	Jan. 31, 2020	Feb. 23, 2020	Aug. 25, 2019	Nov. 26, 2017	May 31, 2020	May 26, 2019	May 27, 2018	Dec. 31, 2019	Nov. 24, 2019	May 27, 2019	Sep. 30, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Expense related to expected incurrence of certain multi-employer plan withdrawal costs						$ 0.3	$ 0.6
Fair value of certain investments					$ 52.4
Fair value of funds which have imposed such gates					0.1
Expense related to defined contribution plans					$ 49.9	$ 39.9	24.5
Maximum
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Maximum allowable funding percentage to be in critical status					65.00%
Maximum allowable funding percentage to be in endangered status					80.00%
Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Minimum required funding percentage to be in the green zone					80.00%
Percentage of plan's total contribution under Forms 5500 (more than)					5.00%
Private equity funds
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Unfunded commitments for additional investments					$ 36.8
Natural resources funds
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Unfunded commitments for additional investments					$ 13.5
Fixed income securities
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Target allocation (percent)					90.00%
Return seeking securities
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Target allocation (percent)					10.00%
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Pension curtailment loss within other comprehensive income (loss)	$ 0.2				$ 0.8		0.7
Effective discount rate assumption	3.86%	2.96%			2.98%	3.88%		3.37%	3.89%
(Increase) decrease to underfunded status of the pension plans	$ (4.3)				$ 0.8
Lump-sum settlement payment		$ 154.6			156.3
Settlement gain		2.1			2.1		(1.3)
Benefit to other comprehensive income (loss)		$ 79.8
Charge reflecting year-end write-off of actuarial losses				$ 3.4	44.8	$ 5.1	$ 3.4
Accumulated benefit obligation					$ 3,870.0	$ 3,730.0
Charge reflecting year-end write-off of actuarial losses percentage					10.00%	10.00%	10.00%
Anticipated contributions to plans in fiscal 2020					$ 32.2
Pension Benefits \| Sopinoff
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Pension curtailment loss within other comprehensive income (loss)			$ 0.6
Effective discount rate assumption			3.90%			3.13%				3.90%	3.78%
(Increase) decrease to underfunded status of the pension plans			$ (12.3)	43.5
Pension curtailment gain (charge) within other comprehensive income (loss)				$ 0.7
Other Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Pension curtailment loss within other comprehensive income (loss)						$ (0.6)
Effective discount rate assumption					2.39%	3.48%
(Increase) decrease to underfunded status of the pension plans						$ 0.6
Lump-sum settlement payment					$ 0.1	0.5
Settlement gain					0.2	$ 1.0
Anticipated contributions to plans in fiscal 2020					$ 10.0