Benefit Plans (Change in benefit obligations funded status) (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, Plan Assets, Foreign Currency Translation Gain (Loss) |
$ (142)
|
$ (292)
|
|
| Defined benefit plan repayment of obligation [Member] |
|
|
|
| Defined Benefit Plan Disclosure [Line Items] |
|
|
|
| Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months |
3,839
|
|
|
| Other Postretirement Benefit Plans, Defined Benefit |
|
|
|
| Defined Benefit Plan Disclosure [Line Items] |
|
|
|
| Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months |
1,510
|
|
|
| Defined Benefit Plan, Benefit Obligation |
11,368
|
12,551
|
$ 14,100
|
| Defined Benefit Plan, Service Cost |
0
|
0
|
0
|
| Defined Benefit Plan, Amortization of Prior Service Cost (Credit) |
0
|
0
|
|
| Defined benefit plan, change in benefit obligation, interest cost |
408
|
457
|
|
| Defined Benefit Plan, Actuarial Net (Gains) Losses |
181
|
(106)
|
|
| Defined Benefit Plan, Benefit Obligation, Benefits Paid |
1,772
|
1,900
|
|
| Defined Benefit Plan, Benefit Obligation, Contributions by Plan Participant |
0
|
0
|
|
| Defined Benefit Plan, Benefits Paid (Deprecated 2017-01-31) |
(1,772)
|
(1,900)
|
|
| Defined Benefit Plan, Plan Assets, Contributions by Plan Participant |
0
|
0
|
|
| Defined Benefit Plan, Plan Assets, Amount |
0
|
0
|
0
|
| Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) |
0
|
0
|
|
| Defined Benefit Plan, Plan Assets, Contributions by Employer |
1,772
|
1,900
|
|
| Defined Benefit Plan, Funded (Unfunded) Status of Plan |
(11,368)
|
(12,551)
|
|
| Defined Benefit Plan, Plan Assets, Foreign Currency Translation Gain (Loss) |
0
|
0
|
|
| Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss) |
0
|
0
|
|
| Other Defined Benefit Pension Plans [Member] |
|
|
|
| Defined Benefit Plan Disclosure [Line Items] |
|
|
|
| Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months |
5,872
|
|
|
| Defined Benefit Plan, Benefit Obligation |
123,190
|
133,672
|
148,848
|
| Defined Benefit Plan, Service Cost |
1,380
|
2,394
|
2,402
|
| Defined Benefit Plan, Amortization of Prior Service Cost (Credit) |
0
|
831
|
|
| Defined benefit plan, change in benefit obligation, interest cost |
2,955
|
3,255
|
|
| Defined Benefit Plan, Actuarial Net (Gains) Losses |
(3,736)
|
(4,402)
|
|
| Defined Benefit Plan, Benefit Obligation, Benefits Paid |
6,466
|
6,150
|
|
| Defined Benefit Plan, Benefit Obligation, Contributions by Plan Participant |
1,046
|
743
|
|
| Defined Benefit Plan, Benefits Paid (Deprecated 2017-01-31) |
(6,466)
|
(6,150)
|
|
| Defined Benefit Plan, Plan Assets, Contributions by Plan Participant |
1,045
|
742
|
|
| Defined Benefit Plan, Plan Assets, Amount |
112,203
|
117,504
|
$ 119,441
|
| Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) |
228
|
6,543
|
|
| Defined Benefit Plan, Plan Assets, Contributions by Employer |
5,071
|
5,005
|
|
| Defined Benefit Plan, Funded (Unfunded) Status of Plan |
(10,987)
|
(16,168)
|
|
| Defined Benefit Plan, Plan Assets, Foreign Currency Translation Gain (Loss) |
(5,179)
|
(8,077)
|
|
| Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss) |
$ (5,661)
|
$ (11,847)
|
|