Pension Plan and Postretirement Health Care and Life Insurance Benefits (Details) - Pension Plan [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 29, 2018	Dec. 30, 2017
Components of net periodic benefit cost:
Service cost	$ 64	$ 58	$ 192	$ 174
Interest cost	221	226	663	678
Expected return on plan assets	(417)	(403)	(1,251)	(1,209)
Amortization of prior service cost	9	9	27	27
Amortization of losses	249	302	747	906
Net periodic benefit cost	$ 126	$ 192	$ 378	$ 576