Net Periodic Benefit Cost (Narratives) (Details) - USD ($) shares in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Mar. 31, 2024
Defined Benefit Plan Disclosure [Line Items]
Effect of dilutive employee stock options and other share-based awards	276	129	268	152
Average basic shares outstanding	28,725	28,619	28,694	28,581
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	$ 40,000	$ 0	$ 81,000	$ 0
Share-based Payment Arrangement, Option [Member]
Defined Benefit Plan Disclosure [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount			748	718
Pension Plans, Defined Benefiit
Defined Benefit Plan Disclosure [Line Items]
Service costs	125,000	157,000	$ 253,000	$ 337,000
Interest cost	3,460,000	2,819,000	6,932,000	5,689,000
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	(2,946,000)	(2,708,000)	(5,892,000)	(5,421,000)
Net amortization	103,000	207,000	204,000	415,000
Net periodic pension (benefit) cost	$ 782,000	$ 475,000	$ 1,578,000	$ 1,020,000
Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year					$ 6,744,000