Pension Plan and Postretirement Health Care and Life Insurance Benefits (Details) - Pension Plan [Member] - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2018	Jul. 01, 2017
Components of net periodic benefit cost:
Service cost	$ 64	$ 58
Interest cost	221	226
Expected return on plan assets	(417)	(403)
Amortization of prior service cost	9	9
Amortization of losses	249	302
Net periodic benefit cost	$ 126	$ 192