Pension And Other Postretirement Benefit Plans (Components Of Company's Net Periodic Benefit Cost) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1,259	$ 1,319	$ 2,511	$ 2,641
Interest cost	2,268	2,882	4,535	5,754
Expected return on plan assets	(3,027)	(3,607)	(6,054)	(7,214)
Net amortization and deferral	83	174	166	348
Net periodic benefit cost	583	768	1,158	1,529
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	17	23	34	47
Interest cost	266	264	528	535
Expected return on plan assets	(11)	(14)	(22)	(28)
Net amortization and deferral	(161)	(160)	(321)	(320)
Net periodic benefit cost	$ 111	$ 113	$ 219	$ 234