Retirement Plans -Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2017	Jan. 01, 2017	Dec. 31, 2017	Jan. 01, 2017
United States Pension Plans of US Entity, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 96	$ 0	$ 278
Interest cost	159	158	493	498
Expected return on plan assets	(132)	(204)	(372)	(612)
Amortization and deferral	69	76	228	340
Net periodic benefit cost	96	126	349	504
Foreign Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Service cost	257	212	756	658
Interest cost	449	441	1,325	1,402
Expected return on plan assets	(565)	(442)	(1,670)	(1,424)
Amortization and deferral	365	238	1,076	756
Net periodic benefit cost	$ 506	$ 449	$ 1,487	$ 1,392