Pension And Other Postretirement Benefit Plans (Components Of Company's Net Periodic Benefit Cost) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1,315	$ 1,280	$ 3,956	$ 3,848
Interest cost	2,875	2,897	8,629	8,696
Expected return on plan assets	(3,606)	(3,887)	(10,820)	(11,663)
Net amortization and deferral	174	205	522	611
Net periodic benefit cost	758	495	2,287	1,492
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	22	24	69	73
Interest cost	259	263	794	793
Expected return on plan assets	(13)	(15)	(41)	(47)
Net amortization and deferral	(157)	(189)	(477)	(569)
Net periodic benefit cost	$ 111	$ 83	$ 345	$ 250