Accumulated Other Comprehensive Loss (Table Text Block)

6 Months Ended

Sep. 30, 2024

Sep. 30, 2023

Table Text Block Supplement [Abstract]

Summary of Accumulated Other Comprehensive Income (Loss) Components, Net of Tax

	Foreign Currency Translation			Unrealized Net Gains (Losses) on Investments and Impact of LFPB (a) Discount Rates			Fair Value of Cash Flow Hedges			Postretirement Benefit Obligation Net Loss		Accumulated Other Comprehensive Loss
	(Unaudited)
	(In thousands)
Balance as of March 31, 2024	$	(53,707	)	$	(176,883	)	$	6,330		$	1,044	$	(223,216	)
Foreign currency translation		217			—			—			—		217
Unrealized net loss on investments and impact of LFBP discount rates		—			(9,445	)		—			—		(9,445	)
Change in fair value of cash flow hedges		—			—			(209	)		—		(209	)
Amounts reclassified into earnings on hedging activities		—			—			(8,178	)		—		(8,178	)
Other comprehensive income (loss)		217			(9,445	)		(8,387	)		—		(17,615	)
Balance as of September 30, 2024	$	(53,490	)	$	(186,328	)	$	(2,057	)	$	1,044	$	(240,831	)

	Foreign Currency Translation			Unrealized Net Gains (Losses) on Investments and Impact of LFPB (a) Discount Rates			Fair Value of Cash Flow Hedges			Postretirement Benefit Obligation Net Loss			Accumulated Other Comprehensive Loss
	(Unaudited)
	(In thousands)
Balance as of March 31, 2023	$	(56,539	)	$	(232,740	)	$	4,007		$	(351	)	$	(285,623	)
Foreign currency translation		(2,380	)		—			—			—			(2,380	)
Unrealized net gain on investments and impact of LFBP discount rates		—			7,047			—			—			7,047
Change in fair value of cash flow hedges		—			—			7,175			—			7,175
Amounts reclassified into earnings on hedging activities		—			—			(1,883	)		—			(1,883	)
Other comprehensive income (loss)		(2,380	)		7,047			5,292			—			9,959
Balance as of September 30, 2023	$	(58,919	)	$	(225,693	)	$	9,299		$	(351	)	$	(275,664	)