Pension And Other Postretirement Benefit Plans (Estimated Future Benefit Payments) (Details) $ in Thousands	Mar. 31, 2018 USD ($)
Pension Benefits [Member]
2019	$ 22,601
2020	16,117
2021	17,622
2022	17,235
2023	17,497
2024 - 2028	91,433
Other Postretirement Benefits [Member]
2019	2,819
2020	2,726
2021	2,639
2022	2,536
2023	2,458
2024 - 2028	$ 10,971

Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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