Loss Contingencies (Narratives) (Details) - USD ($)	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Loss Contingencies [Line Items]
Loss Contingency Accrual, Product Liability, Gross	$ 21,227,000	$ 11,944,000	$ 12,686,000
Loss Contingency Alleged Taxes Owed	7,900,000
Loss Contingency Alleged Taxes Owed Including Penalties And Interest	3,300,000
Accrual for Environmental Loss Contingencies	777,000
Estimated Insurance Recoveries	8,052,000	0	0
Loss Contingency Accrual, Product Liability, Net	13,175,000	11,944,000	12,686,000
Loss Contingency Accrual, Period Increase (Decrease)	1,830,000
Gain (Loss) Related to Litigation Settlement	3,006,000
Proceeds from Legal Settlements	2,842,000
Aggregate amount of reserves	21,227,000	11,944,000	$ 12,686,000	$ 13,582,000
Per occurrence limits on self-insurance for general and product liability coverage	2,000,000
Per occurrence limits on self-insurance for general and product liability coverage for 2014 and thereafter	3,000,000
Coverage minimum	2,000,000
Coverage maximum	$ 6,000,000
Claims maximum period	37 years
Asbestos related aggregate liability	$ 6,956,000,000
Estimated asbestos related liability payments over the next 12 months	2,000,000
Proceeds from Legal Settlements	2,842,000
Product related aggregate liability	5,635,000,000
Minimum
Loss Contingencies [Line Items]
Asbestos-related aggregate liability - Maximum	5,400,000
Maximum
Loss Contingencies [Line Items]
Asbestos-related aggregate liability - Maximum	9,700,000
Litigation Settlement, Amount Awarded from Other Party	1,650,000
Travelers
Loss Contingencies [Line Items]
Increase (Decrease) in Insurance Settlements Receivable	900,000
Other Noncurrent Liabilities [Member]
Loss Contingencies [Line Items]
Loss Contingency Accrual, Product Liability, Gross	17,727,000	$ 8,444,000
Accrued Liabilities
Loss Contingencies [Line Items]
Loss Contingency Accrual, Product Liability, Gross	3,500,000
Gain (Loss) Related to Litigation Settlement	1,500,000
Tax Year 2003/2004 [Member] | Minimum
Loss Contingencies [Line Items]
Loss Contingency Alleged Taxes Owed	2,200,000
Tax Year 2003/2004 [Member] | Maximum
Loss Contingencies [Line Items]
Loss Contingency Alleged Taxes Owed	3,000,000
Magnetek [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	523,000
Asbestos-related aggregate liability - Maximum	565,000
Magnetek [Member] | Bridgeport Facility [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	$ 377,000