Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Amount of cost for defined contribution plan.

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Amount of cash outflow for pension benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes other postretirement benefit.

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Employee Benefit Plans - Narrative (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
	Sep. 14, 2018	Sep. 08, 2018	Sep. 09, 2017	Sep. 08, 2018	Sep. 09, 2017
Defined Benefit Plan Disclosure [Line Items]
Contribution made to defined benefit plan		$ 5.0	$ 4.3	$ 10.5	$ 6.4
Expected future employer contributions for remainder of the fiscal year		4.6		4.6
Defined contribution plan costs		$ 6.5	$ 9.6	$ 20.5	$ 23.2
Subsequent event
Defined Benefit Plan Disclosure [Line Items]
Contribution made to defined benefit pension plans	$ 184.3
Discretionary contributions to minimize pension benefit guaranty corporation premium	$ 150.0