Investments (Tables)

3 Months Ended

Mar. 31, 2025

Investments [Abstract]

Amortized cost, gross unrealized gains and losses and fair value of fixed income securities

Our fixed income securities classified as available-for-sale at March 31, 2025 and December 31, 2024 are shown in tables 7.1a and 7.1b below.

Details of fixed income securities by category as of March 31, 2025
Table	7.1a
(In thousands)		Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)		Fair Value
U.S. Treasury securities and obligations of U.S. government corporations and agencies		$	275,166	$	340	$	(3,812)	$	271,694
Obligations of U.S. states and political subdivisions		2,026,899		3,915		(165,119)		1,865,695
Corporate debt securities		2,858,150		18,082		(93,465)		2,782,767
ABS		180,604		2,702		(915)		182,391
RMBS		375,046		4,463		(21,520)		357,989
CMBS		264,095		421		(5,571)		258,945
CLOs		146,537		76		(32)		146,581
Foreign government debt		4,487		—		(587)		3,900
Commercial paper		15,071		—		—		15,071
Total fixed income securities		$	6,146,055	$	29,999	$	(291,021)	$	5,885,033

Details of fixed income securities by category as of December 31, 2024
Table	7.1b
(In thousands)		Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)		Fair Value
U.S. Treasury securities and obligations of U.S. government corporations and agencies		$	265,349	$	231	$	(5,087)	$	260,493
Obligations of U.S. states and political subdivisions		2,065,953		2,331		(192,789)		1,875,495
Corporate debt securities		2,857,627		12,593		(112,839)		2,757,381
ABS		155,594		2,157		(1,234)		156,517
RMBS		373,485		2,103		(25,528)		350,060
CMBS		243,840		21		(7,990)		235,871
CLOs		199,773		286		—		200,059
Foreign government debt		4,487		—		(689)		3,798
Commercial paper		12,015		—		—		12,015
Total fixed income securities		$	6,178,123	$	19,722	$	(346,156)	$	5,851,689

Amortized cost and fair values of fixed income securities by contractual maturity

The amortized cost and fair values of fixed income securities at March 31, 2025, by contractual maturity, are shown in table 7.2 below. Actual maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Because most mortgage and asset-backed securities are not due at a single maturity date, they are listed in separate categories.

Fixed income securities maturity schedule
Table	7.2
		March 31, 2025
(In thousands)		Amortized cost		Fair Value
Due in one year or less		$	742,080	$	740,345
Due after one year through five years		1,664,014		1,634,666
Due after five years through ten years		1,809,299		1,717,716
Due after ten years		964,380		846,400
		5,179,773		4,939,127
ABS		180,604		182,391
RMBS		375,046		357,989
CMBS		264,095		258,945
CLOs		146,537		146,581
Total		$	6,146,055	$	5,885,033

Cost and fair value of investments in equity securities

The cost and fair value of investments in equity securities at March 31, 2025 and December 31, 2024 are shown in tables 7.3a and 7.3b below.

Details of equity security investments as of March 31, 2025
Table	7.3a
(In thousands)		Cost		Fair Value Gains		Fair Value Losses		Fair Value
Equity securities		$	16,180	$	23	$	(1,288)	$	14,915

Details of equity security investments as of December 31, 2024
Table	7.3b
(In thousands)		Cost		Fair Value Gains		Fair Value Losses		Fair Value
Equity securities		$	16,146	$	8	$	(1,392)	$	14,762

Schedule of realized gains (losses) and proceeds from sale of securities

The net gains (losses) on investments and other financial instruments and the proceeds from the sale of fixed income securities classified as available-for-sale securities are shown in table 7.4 below.

Details of net gains (losses) on investments and other financial instruments
Table	7.4	Three Months Ended March 31,
(in thousands)		2025		2024
Fixed income securities:
Gains on sales		$	349	$	55
Losses on sales		(29)		(5,485)
Equity securities gains (losses):
Changes in fair value		120		(103)
Change in embedded derivative on Home Re Transactions(1)		301		(2,976)
Other:
Gains (losses) on sales		—		1
Market adjustment		—		(1)
Net gains (losses) on investments and other financial instruments		$	741	$	(8,509)
Proceeds from sales of fixed income securities		$	20,737	$	14,886

(1) See Note 8 "Fair Value Measurements" for discussion of the embedded derivative on the Home Re Transactions.

Aging of the fair values of securities in an unrealized loss position

Tables 7.5a and 7.5b below summarize, for all available-for-sale investments in an unrealized loss position at March 31, 2025 and December 31, 2024, the aggregate fair value and gross unrealized loss by the length of time those securities have been continuously in an unrealized loss position. The fair value amounts reported in tables 7.5a and 7.5b are estimated using the process described in Note 8 - “Fair Value Measurements” to these consolidated financial statements and in Note 3 - “Significant Accounting Policies” to the consolidated financial statements in our 2024 Annual Report on Form 10-K.

Unrealized loss aging for securities by type and length of time as of March 31, 2025
Table	7.5a
		Less Than 12 Months				12 Months or Greater				Total
(In thousands)		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
U.S. Treasury securities and obligations of U.S. government corporations and agencies		$	36,101	$	(63)	$	66,902	$	(3,749)	$	103,003	$	(3,812)
Obligations of U.S. states and political subdivisions		378,830		(6,953)		1,204,931		(158,166)		1,583,761		(165,119)
Corporate debt securities		595,473		(5,842)		1,013,348		(87,623)		1,608,821		(93,465)
ABS		9,237		(94)		37,330		(821)		46,567		(915)
RMBS		31,034		(379)		194,501		(21,141)		225,535		(21,520)
CMBS		81,237		(864)		136,860		(4,707)		218,097		(5,571)
CLOs		49,747		(32)		—		—		49,747		(32)
Foreign government debt		—		—		3,900		(587)		3,900		(587)
Total		$	1,181,659	$	(14,227)	$	2,657,772	$	(276,794)	$	3,839,431	$	(291,021)

Unrealized loss aging for securities by type and length of time as of December 31, 2024
Table	7.5b
		Less Than 12 Months				12 Months or Greater				Total
(In thousands)		Fair Value		Unrealized  Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized  Losses
U.S. Treasury securities and obligations of U.S. government corporations and agencies		$	37,017	$	(437)	$	69,959	$	(4,650)	$	106,976	$	(5,087)
Obligations of U.S. states and political subdivisions		409,406		(5,621)		1,195,869		(187,168)		1,605,275		(192,789)
Corporate debt securities		852,752		(10,334)		1,051,862		(102,505)		1,904,614		(112,839)
ABS		20,090		(184)		49,640		(1,050)		69,730		(1,234)
RMBS		171,654		(5,498)		151,893		(20,030)		323,547		(25,528)
CMBS		77,567		(1,774)		151,188		(6,216)		228,755		(7,990)
Foreign government debt		—		—		3,798		(689)		3,798		(689)
Total		$	1,568,486	$	(23,848)	$	2,674,209	$	(322,308)	$	4,242,695	$	(346,156)