Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) - USD ($)	12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2017
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax	$ (5,279,000)	$ (13,297,000)	$ 8,010,000
Change in derivatives qualifying as hedges, tax	(39,000)	(8,000)	(565,000)
Pension Plans
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax	(5,282,000)	(13,261,000)	8,062,000	$ 7,605,000
Postretirement Benefit Plans
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax	48,000	(12,000)	(35,000)	935,000
Defined Benefit Postretirement Life Insurance
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax	$ (45,000)	$ (24,000)	$ (17,000)	$ 747,000