Investments (Table Text Block)

9 Months Ended

Dec. 31, 2025

Investments Debt Equity Securities [Abstract]

Available for sale investments

Available-for-sale investments as of December 31, 2025 were as follows:

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Allowance for Expected Credit Losses			Fair Value
	(Unaudited)
	(In thousands)
U.S. treasury securities and government obligations	$	104,262	$	265	$	(5,320	)	$	—		$	99,207
U.S. government agency mortgage-backed securities		156,754		1,024		(7,672	)		—			150,106
Obligations of states and political subdivisions		133,861		520		(5,904	)		—			128,477
Corporate securities		1,660,382		5,420		(102,335	)		(3,789	)		1,559,678
Mortgage-backed securities		593,955		3,847		(33,834	)		—			563,968
	$	2,649,214	$	11,076	$	(155,065	)	$	(3,789	)	$	2,501,436

Available for sale investments, unrealized losses, fair value

A summary of available-for-sale investments with unrealized losses for which an allowance for credit losses has not been recorded, aggregated by investment category and length of time that individual securities have been in a continuous loss position as of December 31, 2025 and March 31, 2025 were as follows:

	December 31, 2025
	Less than or equal to 1 year					Greater than 1 year					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
	(Unaudited)
	(In thousands)
U.S. treasury securities and government obligations	$	—	$	—		$	92,760	$	(5,320	)	$	92,760	$	(5,320	)
U.S. government agency mortgage-backed securities		37,360		(190	)		19,478		(7,482	)		56,838		(7,672	)
Obligations of states and political subdivisions		18,120		(434	)		62,533		(5,470	)		80,653		(5,904	)
Corporate securities		72,656		(370	)		1,113,633		(101,965	)		1,186,289		(102,335	)
Mortgage-backed securities		35,644		(2,192	)		194,896		(31,642	)		230,540		(33,834	)
	$	163,780	$	(3,186	)	$	1,483,300	$	(151,879	)	$	1,647,080	$	(155,065	)

Adjusted Cost and Estimated Market Value of Available-for-sale Investments

The amortized cost and fair value of available-for-sale investments by contractual maturity were as follows:

	December 31, 2025				March 31, 2025
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
	(Unaudited)
	(In thousands)
Due in one year or less	$	176,399	$	175,753	$	196,238	$	194,896
Due after one year through five years		577,465		568,566		591,589		576,204
Due after five years through ten years		547,894		518,739		611,788		558,430
Due after ten years		753,501		674,410		746,468		634,160
		2,055,259		1,937,468		2,146,083		1,963,690
Mortgage-backed securities		593,955		563,968		562,479		515,808
	$	2,649,214	$	2,501,436	$	2,708,562	$	2,479,498

Available for sale equity investments

Equity investments of common stock and non-redeemable preferred stock were as follows:

	December 31, 2025				March 31, 2025
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
	(Unaudited)
	(In thousands)
Common stocks	$	32,990	$	49,343	$	30,108	$	43,413
Non-redeemable preferred stocks		11,045		8,075		25,144		22,136
	$	44,035	$	57,418	$	55,252	$	65,549

Carrying value of Investments, other

The carrying value of the other investments was as follows:

	December 31,		March 31,
	2025		2025
	(Unaudited)
	(In thousands)
Mortgage loans, net	$	699,878	$	657,567
Policy loans		12,521		11,868
Other investments		8,314		8,819
	$	720,713	$	678,254