Net Periodic Benefit Cost (Narratives) (Details)	9 Months Ended
	Dec. 31, 2015 USD ($) shares
Defined Benefit Plan Disclosure [Line Items]
Planned contributions to pension plans in fiscal 2016	$ 5,895,000
Magnetek [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Fair Value of Plan Assets	127,726,000
Pension and Other Postretirement Defined Benefit Plans, Liabilities	41,129,000
Pension Expense	1,034,000
Multiemployer Plans, Accumulated Benefit Obligation	$ 168,855,000
Magnetek [Member]
Defined Benefit Plan Disclosure [Line Items]
Total number of shares of common stock available for grant | shares	397,602