Benefit Plans (Expected payments to be made to plan participants) (Details) - USD ($)
$ in Thousands |
12 Months Ended |
Mar. 31, 2020 |
Mar. 31, 2019 |
Mar. 31, 2018 |
| Defined Benefit Plan Disclosure [Line Items] |
|
|
|
| Defined Benefit Plan, Gross Prescription Drug Subsidy Receipts Received (Deprecated 2017-01-31) |
$ 708
|
$ 706
|
|
| Other Defined Benefit Pension Plans [Member] |
|
|
|
| Defined Benefit Plan Disclosure [Line Items] |
|
|
|
| Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) |
(3,736)
|
(4,402)
|
|
| Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months |
5,872
|
|
|
| Defined Benefit Plan, Expected Future Benefit Payments in Year Two |
6,025
|
|
|
| Defined Benefit Plan, Expected Future Benefit Payments in Year Three |
6,600
|
|
|
| Defined Benefit Plan, Expected Future Benefit Payments in Year Four |
6,336
|
|
|
| Defined Benefit Plan, Expected Future Benefit Payments in Year Five |
6,518
|
|
|
| Defined Benefit Plan, Expected Future Benefit Payments in Five Fiscal Years Thereafter |
35,292
|
|
|
| Defined Benefit Plan, Amortization of Prior Service Cost (Credit) |
69
|
51
|
$ 0
|
| Other Postretirement Benefit Plans, Defined Benefit |
|
|
|
| Defined Benefit Plan Disclosure [Line Items] |
|
|
|
| Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) |
181
|
(106)
|
|
| Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months |
1,510
|
|
|
| Defined Benefit Plan, Expected Future Benefit Payments in Year Two |
1,392
|
|
|
| Defined Benefit Plan, Expected Future Benefit Payments in Year Three |
1,252
|
|
|
| Defined Benefit Plan, Expected Future Benefit Payments in Year Four |
1,115
|
|
|
| Defined Benefit Plan, Expected Future Benefit Payments in Year Five |
1,007
|
|
|
| Defined Benefit Plan, Expected Future Benefit Payments in Five Fiscal Years Thereafter |
3,726
|
|
|
| Defined Benefit Plan, Amortization of Prior Service Cost (Credit) |
$ (3,263)
|
$ (3,263)
|
$ (3,263)
|