Investments (Table Text Block)

3 Months Ended

Jun. 30, 2016

Mar. 31, 2016

Investments Debt Equity Securities [Abstract]

Available-for-Sale Investments

Available-for-sale investments at June 30, 2016 were as follows:

		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses More than 12 Months		Gross Unrealized Losses Less than 12 Months		Estimated Market Value
		(Unaudited)
		(In thousands)
U.S. treasury securities and government obligations	$	98,134	$	6,159	$	–	$	(50)	$	104,243
U.S. government agency mortgage-backed securities		30,884		1,741		(5)		–		32,620
Obligations of states and political subdivisions		165,322		14,339		(32)		(16)		179,613
Corporate securities		1,232,287		45,160		(7,890)		(16,275)		1,253,282
Mortgage-backed securities		42,850		855		–		(7)		43,698
Redeemable preferred stocks		15,977		530		–		(191)		16,316
Common stocks		17,732		8,700		(10)		(35)		26,387
	$	1,603,186	$	77,484	$	(7,937)	$	(16,574)	$	1,656,159

Available-for-sale investments at March 31, 2016 were as follows:

		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses More than 12 Months		Gross Unrealized Losses Less than 12 Months		Estimated Market Value
		(In thousands)
U.S. treasury securities and government obligations	$	85,861	$	3,791	$	–	$	(193)	$	89,459
U.S. government agency mortgage-backed securities		21,845		1,596		(6)		(39)		23,396
Obligations of states and political subdivisions		166,725		10,660		(81)		(414)		176,890
Corporate securities		1,143,125		26,861		(8,013)		(28,181)		1,133,792
Mortgage-backed securities		42,991		475		–		(62)		43,404
Redeemable preferred stocks		17,977		556		–		(105)		18,428
Common stocks		17,732		7,822		(10)		(375)		25,169
	$	1,496,256	$	51,761	$	(8,110)	$	(29,369)	$	1,510,538

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

The adjusted cost and estimated market value of available-for-sale investments by contractual maturity, were as follows:

		June 30, 2016				March 31, 2016
		Amortized Cost		Estimated Market Value		Amortized Cost		Estimated Market Value
		(Unaudited)
		(In thousands)
Due in one year or less	$	31,772	$	32,158	$	48,679	$	49,146
Due after one year through five years		298,190		307,633		250,576		256,597
Due after five years through ten years		628,082		644,932		557,984		557,961
Due after ten years		568,583		585,035		560,317		559,833
		1,526,627		1,569,758		1,417,556		1,423,537
Mortgage backed securities		42,850		43,698		42,991		43,404
Redeemable preferred stocks		15,977		16,316		17,977		18,428
Equity securities		17,732		26,387		17,732		25,169
	$	1,603,186	$	1,656,159	$	1,496,256	$	1,510,538