Accumulated Other Comprehensive Loss (AOCL) (Components) (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Mar. 31, 2024
Equity [Abstract]
Derivatives	$ (1,004)	$ (15)
Pension and other postretirement benefit liabilities	(67,592)	(68,722)
Cumulative translation adjustment	(4,858)	(5,611)
Total accumulated other comprehensive loss	$ (73,454)	$ (74,348)

Amount, after tax, of accumulated increase (decrease) in equity from transaction and other event and circumstance from nonowner source.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant