Other Comprehensive Loss - Components Reclassified from AOCI to Earnings (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Pensions and other postretirement benefits
Reclassification Out Of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from accumulated other comprehensive loss to net income, gross	$ 395	$ 367	$ 1,185	$ 1,099
Tax effects of amounts reclassified from accumulated other comprehensive loss to net income	(83)	(82)	(251)	(246)
Amounts reclassified from accumulated other comprehensive loss to net income, net	312	285	934	853
Actuarial loss
Reclassification Out Of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from accumulated other comprehensive loss to net income, gross	560	534	1,680	1,601
Amortization of prior service cost
Reclassification Out Of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from accumulated other comprehensive loss to net income, gross	(165)	(167)	(495)	(502)
Derivatives
Reclassification Out Of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from accumulated other comprehensive loss to net income, gross	729	458	3,189	1,445
Tax effects of amounts reclassified from accumulated other comprehensive loss to net income	(153)	(96)	(669)	(303)
Amounts reclassified from accumulated other comprehensive loss to net income, net	$ 576	$ 362	$ 2,520	$ 1,142