Pension (detail) - USD ($)	3 Months Ended		6 Months Ended
	Oct. 01, 2016	Sep. 26, 2015	Oct. 01, 2016	Sep. 26, 2015
General Discussion Of Pension And Other Postretirement Benefits [Abstract]
Defined Benefit Plan, Service Cost	$ 2,164,000	$ 2,519,000	$ 4,328,000	$ 5,039,000
Defined Benefit Plan, Interest Cost	1,919,000	2,177,000	3,838,000	4,355,000
Defined Benefit Plan, Expected Return on Plan Assets	(2,978,000)	(2,625,000)	(5,958,000)	(5,252,000)
Defined Benefit Plan, Actuarial Net (Gains) Losses	679,000	844,000	1,358,000	1,687,000
Defined Benefit Plan, Amortization of Transition Obligations (Assets)	27,000	27,000	55,000	55,000
Defined Benefit Plan, Net Periodic Benefit Cost	$ 1,811,000	$ 2,942,000	3,621,000	5,884,000
Defined Benefit Plan, Contributions by Employer			$ 300,000	$ 600,000