Benefit Plans (Amounts recognized in balance sheets) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Mar. 31, 2018
Other Postretirement Benefit Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Liability, Defined Benefit Plan, Current	$ (1,633)	$ (1,906)
Liability, Defined Benefit Plan, Noncurrent	(10,918)	(12,194)
Liability, Defined Benefit Pension Plan	(12,551)	(14,100)
Other Defined Benefit Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Liability, Defined Benefit Plan, Current	0	0
Liability, Defined Benefit Plan, Noncurrent	(16,168)	(29,407)
Liability, Defined Benefit Pension Plan	$ (16,168)	$ (29,407)

Amount of liability, recognized in statement of financial position, for defined benefit pension plan. Excludes other postretirement benefit plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(15))
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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