Employee Benefit Plans (Tables)

4 Months Ended

Jun. 16, 2018

Retirement Benefits [Abstract]

Schedule of Components of Net Pension and Post-retirement Expense

The following tables provide the components of net pension and post-retirement expense (in millions):

	16 weeks ended
	Pension						Other post-retirement benefits
	June 16, 2018			June 17, 2017			June 16, 2018			June 17, 2017
Estimated return on plan assets	$	(34.6	)	$	(36.8	)	$	—		$	—
Service cost	16.1			15.3			0.3			0.3
Interest cost	26.4			27.1			0.2			0.3
Amortization of prior service cost	—			0.1			1.1			1.1
Amortization of net actuarial (gain) loss	(1.9		)	0.1			(0.1		)	—
Net expense	$	6.0		$	5.8		$	1.5		$	1.7