Investments (Tables)

9 Months Ended

Sep. 30, 2021

Investments [Abstract]

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

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

			Gross		Gross
		Amortized Cost/	Unrealized		Unrealized
	Carrying Value		Gains		Losses		Fair Value
As of September 30, 2021
U.S. Treasury securities and obligations of U.S. Government	$	66,354	$	142	$	—	$	66,496
Corporate bonds		119,341		2,829		(73)		122,097
Corporate bank loans		86,749		117		(532)		86,334
Municipal bonds		40,618		421		(68)		40,971
Mortgage-backed		1,967		55		(4)		2,018
Total debt securities		315,029		3,564		(677)		317,916
Total equity securities		39,129		8,148		(1,915)		45,362
Total investments	$	354,158	$	11,712	$	(2,592)	$	363,278
			Gross		Gross
		Amortized Cost/	Unrealized		Unrealized
As of December 31, 2020	Carrying Value		Gains		Losses		Fair Value
U.S. Treasury securities and obligations of U.S. Government	$	179,259	$	487	$	—	$	179,746
Corporate bonds		214,666		5,086		(384)		219,368
Corporate bank loans		53,650		3		(871)		52,782
Municipal bonds		49,833		756		(50)		50,539
Mortgage-backed		4,759		114		(29)		4,844
Total debt securities		502,167		6,446		(1,334)		507,279
Total equity securities		26,988		5,648		(3,248)		29,388
Total investments	$	529,155	$	12,094	$	(4,582)	$	536,667

Major Categories of Net Investment Gains (Losses) on Investments

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

	Three Months Ended September 30,				Nine Months Ended September 30,
	2021		2020		2021		2020
U.S. Treasury securities and obligations of U.S. Government	$	—	$	(3)	$	—	$	(3)
Corporate bonds		133		352		494		766
Corporate bank loans		14		66		105		(19)
Municipal bonds		(18)		(25)		(12)		1,397
Equity securities		930		—		4,701		3,471
Gain on investments		1,059		390		5,288		5,612
Other-than-temporary impairments		—		(1,692)		—		(1,692)
Unrealized losses on other investments		—		(262)		—		(2,136)
Unrealized (losses) gains on equity investments		(1,592)		937		3,834		(29,683)
Investment (losses) gains, net	$	(533)	$	(627)	$	9,122	$	(27,899)

Summary of Gross 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, 2021 and December 31, 2020 (in thousands):

	As of September 30, 2021
	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	$	—	$	—	$	—	$	—	$	—	$	—
Corporate bonds		—		—		2,592		(73)		2,592		(73)
Corporate bank loans		27,235		(125)		20,443		(407)		47,678		(532)
Municipal bonds		4,000		(57)		999		(11)		4,999		(68)
Mortgage-backed		—		—		11		(4)		11		(4)
Total debt securities		31,235		(182)		24,045		(495)		55,280		(677)
Total equity securities		9,514		(335)		4,143		(1,580)		13,657		(1,915)
Total investments with unrealized losses	$	40,749	$	(517)	$	28,188	$	(2,075)	$	68,937	$	(2,592)

	As of December 31, 2020
	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	$	—	$	—	$	—	$	—	$	—	$	—
Corporate bonds		7,801		(186)		3,556		(198)		11,357		(384)
Corporate bank loans		45,233		(559)		4,144		(312)		49,377		(871)
Municipal bonds		2,859		(33)		1,154		(17)		4,013		(50)
Mortgage-backed		635		(25)		14		(4)		649		(29)
Total debt securities		56,528		(803)		8,868		(531)		65,396		(1,334)
Total equity securities		9,572		(1,610)		1,848		(1,638)		11,420		(3,248)
Total investments with unrealized losses	$	66,100	$	(2,413)	$	10,716	$	(2,169)	$	76,816	$	(4,582)

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

The amortized cost and estimated fair value of debt securities at September 30, 2021 by contractual maturity are as follows. Expected maturities may differ from contractual maturities because certain borrowers may have the right to call or prepay obligations with or without penalties.

	Amortized Cost		Fair Value
	(in thousands)
Due in one year or less	$	125,303	$	126,261
Due after one year through five years		114,399		116,086
Due after five years through ten years		64,251		64,191
Due after ten years		9,109		9,360
Mortgage-backed		1,967		2,018
	$	315,029	$	317,916