Investments (Tables)

6 Months Ended

Jun. 30, 2018

Gross Unrealized Gains and Losses and Amortized Cost and Fair Value of Investments Classified as Held-to-maturity

The gross unrealized gains and losses on, and the amortized cost and fair value of, those investments classified as held-to-maturity at June 30, 2018 are summarized as follows:

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
	(in thousands)
States and political subdivisions	$	432,914	$	4,714	$	(2,891	)	$	434,737
Corporate bonds		98,702		38		(724	)		98,016
U.S. agency-based mortgage-backed securities		9,038		420		(71	)		9,387
U.S. Treasury securities and obligations of U.S.    government agencies		64,063		385		(691	)		63,757
Asset-backed securities		1,160		25		(10	)		1,175
Totals	$	605,877	$	5,582	$	(4,387	)	$	607,072

The gross unrealized gains and losses on, and the amortized cost and fair value of, those investments classified as held-to-maturity at December 31, 2017 are summarized as follows:

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
	(in thousands)
States and political subdivisions	$	460,428	$	9,628	$	(955	)	$	469,101
Corporate bonds		100,024		190		(167	)		100,047
U.S. agency-based mortgage-backed securities		10,260		625		(40	)		10,845
U.S. Treasury securities and obligations    of U.S. government agencies		57,657		548		(198	)		58,007
Asset-backed securities		1,299		25		(15	)		1,309
Totals	$	629,668	$	11,016	$	(1,375	)	$	639,309

Gross Unrealized Gains and Losses and Cost or Amortized Cost and Fair Value of Investments Classified as Available-for-sale

The gross unrealized gains and losses on, and the cost or amortized cost and fair value of, those investments classified as available-for-sale at June 30, 2018 are summarized as follows:

	Cost or Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
	(in thousands)
Fixed maturity:
States and political subdivisions	$	217,427	$	3,368	$	(2,495	)	$	218,300
Corporate bonds		144,950		60		(1,051	)		143,959
U.S. agency-based mortgage-backed securities		13,730		—		(368	)		13,362
U.S. Treasury securities and obligations    of U.S. government agencies		67,251		—		(2,110	)		65,141
Total fixed maturity		443,358		3,428		(6,024	)		440,762
Equity securities		13,590		—		—			13,590
Totals	$	456,948	$	3,428	$	(6,024	)	$	454,352

The gross unrealized gains and losses on, and the cost or amortized cost and fair value of, those investments classified as available-for-sale at December 31, 2017 are summarized as follows:

	Cost or Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
	(in thousands)
Fixed maturity:
States and political subdivisions	$	244,898	$	6,819	$	(577	)	$	251,140
Corporate bonds		130,210		224		(212	)		130,222
U.S. agency-based mortgage-backed securities		18,813		—		(799	)		18,014
U.S. Treasury securities and obligations    of U.S. government agencies		67,315		29		(1,126	)		66,218
Total fixed maturity		461,236		7,072		(2,714	)		465,594
Equity securities		8,503		779		—			9,282
Totals	$	469,739	$	7,851	$	(2,714	)	$	474,876

Investment Securities Continuous Unrealized Loss Position

The following table summarizes the fair value and gross unrealized losses on securities, aggregated by major investment category and length of time that the individual securities have been in a continuous unrealized loss position:

	Less Than 12 Months				12 Months or Greater				Total
	Fair Value of Investments with Unrealized Losses		Gross Unrealized Losses		Fair Value of Investments with Unrealized Losses		Gross Unrealized Losses		Fair Value of Investments with Unrealized Losses		Gross Unrealized Losses
	(in thousands)
June 30, 2018
Held-to-Maturity
Fixed maturity securities:
States and political subdivisions	$	204,459	$	2,568	$	12,424	$	323	$	216,883	$	2,891
Corporate bonds		86,816		703		2,237		21		89,053		724
U.S. agency-based mortgage-backed securities		2,524		71		—		—		2,524		71
U.S. Treasury securities and obligations    of U.S. government agencies		43,357		461		11,659		230		55,016		691
Asset-backed securities		565		10		—		—		565		10
Total held-to-maturity securities		337,721		3,813		26,320		574		364,041		4,387
Available-for-Sale
Fixed maturity securities:
States and political subdivisions	$	77,359	$	1,356	$	15,476	$	1,139	$	92,835	$	2,495
Corporate bonds		121,848		1,016		1,021		35		122,869		1,051
U.S. agency-based mortgage-backed securities		11,557		312		1,805		56		13,362		368
U.S. Treasury securities and obligations    of U.S. government agencies		18,071		630		47,070		1,480		65,141		2,110
Total available-for-sale securities		228,835		3,314		65,372		2,710		294,207		6,024
Total	$	566,556	$	7,127	$	91,692	$	3,284	$	658,248	$	10,411

	Less Than 12 Months				12 Months or Greater				Total
	Fair Value of Investments with Unrealized Losses		Gross Unrealized Losses		Fair Value of Investments with Unrealized Losses		Gross Unrealized Losses		Fair Value of Investments with Unrealized Losses		Gross Unrealized Losses
	(in thousands)
December 31, 2017
Held-to-Maturity
Fixed maturity securities:
States and political subdivisions	$	110,698	$	654	$	19,895	$	301	$	130,593	$	955
Corporate bonds		56,425		156		4,121		11		60,546		167
U.S. agency-based mortgage-backed securities		2,798		40		—		—		2,798		40
U.S. Treasury securities and obligations    of U.S. government agencies		48,153		122		3,948		76		52,101		198
Asset-backed securities		—		—		967		15		967		15
Total held-to-maturity securities		218,074		972		28,931		403		247,005		1,375
Available-for-Sale
Fixed maturity securities:
States and political subdivisions	$	23,365	$	86	$	19,153	$	491	$	42,518	$	577
Corporate bonds		82,795		171		5,888		41		88,683		212
U.S. agency-based mortgage-backed securities		14,686		59		3,328		740		18,014		799
U.S. Treasury securities and obligations    of U.S. government agencies		14,730		204		47,716		922		62,446		1,126
Total available-for-sale securities		135,576		520		76,085		2,194		211,661		2,714
Total	$	353,650	$	1,492	$	105,016	$	2,597	$	458,666	$	4,089

Held-to-Maturity Securities [Member]

Summary of Amortized Cost and Fair Value of Investments in Fixed Maturity Securities, by Contractual Maturity

A summary of the amortized cost and fair value of investments in fixed maturity securities, classified as held-to-maturity at June 30, 2018, by contractual maturity, is as follows:

	Amortized Cost		Fair Value
	(in thousands)
Maturity:
Within one year	$	91,818	$	92,103
After one year through five years		252,775		252,787
After five years through ten years		90,966		91,281
After ten years		160,120		160,339
U.S. agency-based mortgage-backed securities		9,038		9,387
Asset-backed securities		1,160		1,175
Totals	$	605,877	$	607,072

Available-for-Sale Securities [Member]

Summary of Amortized Cost and Fair Value of Investments in Fixed Maturity Securities, by Contractual Maturity

A summary of the amortized cost and fair value of investments in fixed maturity securities, classified as available-for-sale at June 30, 2018, by contractual maturity, is as follows:

	Amortized Cost		Fair Value
	(in thousands)
Maturity:
Within one year	$	69,793	$	69,608
After one year through five years		158,974		156,733
After five years through ten years		32,366		31,784
After ten years		168,495		169,275
U.S. agency-based mortgage-backed securities		13,730		13,362
Totals	$	443,358	$	440,762