Pension And Other Postretirement Benefit Plans (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2031
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss expected in net periodic benefit cost during next fiscal year	$ 3,700
Prior service benefit expected in net periodic benefit cost during next fiscal year	$ 1,200
Percentage of total plan assets	98.00%
Percentage of total projected benefit obligation	86.00%
Pension and Other Postretirement Benefits Cost (Reversal of Cost)	$ 3,000	$ 2,900	$ 2,700
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Funded status of the plans, end of year	$ 21,037	$ 26,741
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Revised healthcare cost trend assumption	6.17%	6.17%	7.34%
Year that rate reaches healthcare cost trend rate	2031
Funded status of the plans, end of year	$ 22,251	$ 25,893
Other Postretirement Benefits [Member] | Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Revised healthcare cost trend assumption				4.44%
ERISA Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected company contributions in next fiscal year	0
Nonqualified Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected company contributions in next fiscal year	2,300
Nonqualified Plan [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Funded status of the plans, end of year	33,300
Nonqualified Plan [Member] | Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Funded status of the plans, end of year	$ 20,500