PENSION AND POSTRETIREMENT BENEFITS (Tables)

9 Months Ended

Feb. 23, 2020

Compensation And Retirement Disclosure [Abstract]

Components of Pension Benefit and Other Postretirement Benefit Costs

Components of pension benefit and other postretirement benefit costs are:

	Pension Benefits
	Thirteen weeks ended						Thirty-nine weeks ended
	February 23, 2020			February 24, 2019			February 23, 2020			February 24, 2019
Service cost	$	2.8		$	2.8		$	8.4		$	8.3
Interest cost		27.8			34.0			89.8			98.7
Expected return on plan assets		(42.0	)		(44.6	)		(124.7	)		(130.1	)
Amortization of prior service cost		0.7			0.7			2.0			2.1
Curtailment loss		0.2			—			0.8			—
Settlement gain		(2.1	)		—			(2.1	)		—
Benefit cost (benefit) — Company plans		(12.6	)		(7.1	)		(25.8	)		(21.0	)
Pension benefit cost — multi-employer plans		1.5			1.4			5.0			4.9
Total benefit cost (benefit)	$	(11.1	)	$	(5.7	)	$	(20.8	)	$	(16.1	)

	Postretirement Benefits
	Thirteen weeks ended						Thirty-nine weeks ended
	February 23, 2020			February 24, 2019			February 23, 2020			February 24, 2019
Service cost	$	—		$	—		$	0.1		$	0.1
Interest cost		0.6			1.0			1.9			2.9
Amortization of prior service benefit		(0.5	)		(0.5	)		(1.5	)		(1.5	)
Recognized net actuarial gain		(1.1	)		(0.4	)		(3.4	)		(1.2	)
Curtailment gain		—			—			—			(0.6	)
Total cost (benefit)	$	(1.0	)	$	0.1		$	(2.9	)	$	(0.3	)