Investments (Tables)

9 Months Ended

Sep. 30, 2017

Investments [Abstract]

Amortized Cost and Estimated Fair Value of Investments in Debt and Equity Securities by Category

The amortized cost and estimated fair value of investments in debt and equity securities by category is as follows (in thousands):

			Gross		Gross
	Amortized		Unrealized		Unrealized		Fair
As of September 30, 2017	Cost		Gains		Losses		Value
U.S. Treasury securities and obligations of U.S. Government	$	42,034	$	6	$	(6)	$	42,034
Corporate bonds		283,851		1,810		(1,040)		284,621
Collateralized corporate bank loans		123,070		628		(455)		123,243
Municipal bonds		148,473		917		(407)		148,983
Mortgage-backed		19,457		64		(168)		19,353
Total debt securities		616,885		3,425		(2,076)		618,234
Total equity securities		26,681		22,237		(1,119)		47,799
Total other investments		3,763		458		-		4,221
Total investments	$	647,329	$	26,120	$	(3,195)	$	670,254
As of December 31, 2016
U.S. Treasury securities and obligations of U.S. Government	$	41,976	$	66	$	(20)	$	42,022
Corporate bonds		224,915		1,722		(575)		226,062
Collateralized corporate bank loans		105,220		959		(170)		106,009
Municipal bonds		165,900		956		(2,961)		163,895
Mortgage-backed		59,773		49		(353)		59,469
Total debt securities		597,784		3,752		(4,079)		597,457
Total equity securities		31,449		21,052		(790)		51,711
Total other investments		3,763		1,188		-		4,951
Total investments	$	632,996	$	25,992	$	(4,869)	$	654,119

Summary of Realized Gain (Loss) on Investments

Major categories of net realized gains (losses) on investments are summarized as follows (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2017		2016		2017		2016
U.S. Treasury securities and obligations of U.S. Government	$	-	$	-	$	-	$	-
Corporate bonds		(107)		(81)		(125)		(1)
Collateralized corporate bank loans		8		(98)		56		(116)
Municipal bonds		120		(97)		204		(165)
Mortgage-backed		(1)		(1)		(1)		(1)
Equity securities		3,168		1,382		5,545		1,872
Gain on investments		3,188		1,105		5,679		1,589
Change in unrealized losses on other investments		(228)		-		(731)		-
Other-than-temporary impairments		(850)		-		(4,257)		(2,888)
Net realized gains (losses)	$	2,110	$	1,105	$	691	$	(1,299)

Summary of Gross Unrealized Losses for Investments that have been Continuously in Unrealized Loss Position

The following schedules summarize the gross unrealized losses showing the length of time that investments have been continuously in an unrealized loss position as of September 30, 2017 and December 31, 2016 (in thousands):

	As of September 30, 2017
	12 months or less				Longer than 12 months				Total
			Unrealized				Unrealized				Unrealized
	Fair Value		Losses		Fair Value		Losses		Fair Value		Losses
U.S. Treasury securities and obligations of U.S. Government	$	36,977	$	(6)	$	-	$	-	$	36,977	$	(6)
Corporate bonds		99,803		(1,040)		-		-		99,803		(1,040)
Collateralized corporate bank loans		33,925		(385)		2,474		(70)		36,399		(455)
Municipal bonds		27,971		(355)		2,707		(52)		30,678		(407)
Mortgage-backed		12,886		(166)		1,228		(2)		14,114		(168)
Total debt securities		211,562		(1,952)		6,409		(124)		217,971		(2,076)
Total equity securities		3,251		(1,119)		-		-		3,251		(1,119)
Total other investments		582		-		-		-		582		-
Total investments	$	215,395	$	(3,071)	$	6,409	$	(124)	$	221,804	$	(3,195)
	As of December 31, 2016
	12 months or less				Longer than 12 months				Total
			Unrealized				Unrealized				Unrealized
	Fair Value		Losses		Fair Value		Losses		Fair Value		Losses
U.S. Treasury securities and obligations of U.S. Government	$	7,037	$	(20)	$	-	$	-	$	7,037	$	(20)
Corporate bonds		86,592		(575)		-		-		86,592		(575)
Collateralized corporate bank loans		2,637		(7)		8,314		(163)		10,951		(170)
Municipal bonds		70,633		(1,327)		13,574		(1,634)		84,207		(2,961)
Mortgage-backed		29,475		(348)		2,430		(5)		31,905		(353)
Total debt securities		196,374		(2,277)		24,318		(1,802)		220,692		(4,079)
Total equity securities		4,109		(483)		2,037		(307)		6,146		(790)
Total other investments		-		-		-		-		-		-
Total investments	$	200,483	$	(2,760)	$	26,355	$	(2,109)	$	226,838	$	(4,869)

Carrying Value of Other Invested Assets Portfolio

Details regarding the carrying value of the other investments portfolio as of September 30, 2017 and December 31, 2016 were as follows (in thousands):

	September 30,		December 31,
	2017		2016
Investment Type
Equity warrant	$	4,221	$	4,951
Total other investments	$	4,221	$	4,951

Schedule of Amortized Cost and Estimated Fair Value of Debt Securities by Contractual Maturities

	Amortized		Fair
	Cost		Value
	(in thousands)
Due in one year or less	$	163,460	$	163,697
Due after one year through five years		254,385		255,618
Due after five years through ten years		134,207		134,902
Due after ten years		45,376		44,664
Mortgage-backed		19,457		19,353
	$	616,885	$	618,234