Pension Benefits (Narrative) (Details) $ in Thousands		3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 30, 2020 USD ($)	Oct. 31, 2020 plan	Jan. 31, 2021 USD ($)	Apr. 30, 2020 USD ($) plan
Defined Benefit Plan Disclosure [Line Items]
Number of defined benefit pension plans | plan		2		1
Pension contribution			$ 0	$ 500
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Expected termination costs	$ 1,600