The amortized cost and fair value of available-for-sale fixed maturities were as follows:


	March 31, 2026
			Allowance			Amortized Cost,		Gross		Gross
	Amortized		for Credit			Net of Allowance		Unrealized		Unrealized
(in millions)	Cost		Losses			for Credit Loses		Gains		Losses		Fair Value
U.S. Treasury and government agencies	$	477.7	$	—		$	477.7	$	1.4	$	40.4	$	438.7
Foreign governments		2.8		—			2.8		0.1		—		2.9
Municipals		959.0		—			959.0		2.7		68.5		893.2
Corporates		4,388.5		(0.3	)		4,388.2		34.8		74.9		4,348.1
Residential mortgage-backed		2,389.8		—			2,389.8		20.1		85.6		2,324.3
Commercial mortgage-backed		880.2		—			880.2		0.3		25.6		854.9
Other asset-backed		1,114.1		—			1,114.1		3.5		3.5		1,114.1
Total fixed maturities	$	10,212.1	$	(0.3	)	$	10,211.8	$	62.9	$	298.5	$	9,976.2


	December 31, 2025
			Allowance			Amortized Cost,		Gross		Gross
	Amortized		for Credit			Net of Allowance		Unrealized		Unrealized
(in millions)	Cost		Losses			for Credit Loses		Gains		Losses		Fair Value
U.S. Treasury and government agencies	$	491.3	$	—		$	491.3	$	2.4	$	38.2	$	455.5
Foreign governments		2.5		—			2.5		0.2		—		2.7
Municipals		910.8		—			910.8		4.1		67.2		847.7
Corporates		4,239.3		(0.2	)		4,239.1		71.4		57.0		4,253.5
Residential mortgage-backed		2,472.2		—			2,472.2		32.4		82.8		2,421.8
Commercial mortgage-backed		610.2		—			610.2		1.0		21.3		589.9
Other asset-backed		959.6		—			959.6		6.5		0.7		965.4
Total fixed maturities	$	9,685.9	$	(0.2	)	$	9,685.7	$	118.0	$	267.2	$	9,536.5

The Company enters into various agreements that may require its fixed maturities to be held as collateral by others. At March 31, 2026 and December 31, 2025, fixed maturities with fair values of $332.6 million and $339.2 million, respectively, were held as collateral for the Federal Home Loan Bank (“FHLB”) collateralized borrowing program. Additionally, the Company deposits funds with various state governmental authorities and trustees. For a discussion of the Company’s deposits with these state governmental authorities and trustees, see Note 2 – “Investments” in the Notes to Consolidated Financial Statements in the Company’s 2025 Annual Report on Form 10-K.

The following tables provide information about the Company’s available-for-sale fixed maturity securities that were in an unrealized loss position at March 31, 2026 and December 31, 2025, including the length of time the securities have been in an unrealized loss position:


	March 31, 2026
	12 months or less				Greater than 12 months				Total
	Gross				Gross				Gross
	Unrealized		Fair		Unrealized		Fair		Unrealized		Fair
(in millions)	Losses		Value		Losses		Value		Losses		Value
Investment grade:
U.S. Treasury and government agencies	$	0.2	$	20.9	$	40.2	$	307.1	$	40.4	$	328.0
Municipals		2.9		195.2		65.6		511.4		68.5		706.6
Corporates		13.6		1,296.1		52.7		586.1		66.3		1,882.2
Residential mortgage-backed		2.9		456.9		82.7		503.8		85.6		960.7
Commercial mortgage-backed		5.3		525.9		19.5		259.9		24.8		785.8
Other asset-backed		3.1		543.2		0.3		17.4		3.4		560.6
Total investment grade		28.0		3,038.2		261.0		2,185.7		289.0		5,223.9
Below investment grade:
Foreign governments		—		0.7		—		—		—		0.7
Corporates		4.2		149.9		4.4		33.2		8.6		183.1
Residential mortgage-backed		—		0.5		—		—		—		0.5
Commercial mortgage-backed		—		—		0.8		4.8		0.8		4.8
Other asset-backed		0.1		2.5		—		—		0.1		2.5
Total below investment grade		4.3		153.6		5.2		38.0		9.5		191.6
Total fixed maturities	$	32.3	$	3,191.8	$	266.2	$	2,223.7	$	298.5	$	5,415.5


	December 31, 2025
	12 months or less				Greater than 12 months				Total
	Gross				Gross				Gross
	Unrealized		Fair		Unrealized		Fair		Unrealized		Fair
(in millions)	Losses		Value		Losses		Value		Losses		Value
Investment grade:
U.S. Treasury and government agencies	$	—	$	11.9	$	38.2	$	319.7	$	38.2	$	331.6
Municipals		0.6		56.3		66.6		550.3		67.2		606.6
Corporates		1.0		271.3		51.2		704.2		52.2		975.5
Residential mortgage-backed		0.5		128.7		82.3		521.7		82.8		650.4
Commercial mortgage-backed		0.5		122.5		20.0		284.3		20.5		406.8
Other asset-backed		0.5		82.9		0.2		24.3		0.7		107.2
Total investment grade		3.1		673.6		258.5		2,404.5		261.6		3,078.1
Below investment grade:
Corporates		2.2		37.5		2.6		34.8		4.8		72.3
Commercial mortgage-backed		—		—		0.8		4.9		0.8		4.9
Other asset-backed		—		1.3		—		—		—		1.3
Total below investment grade		2.2		38.8		3.4		39.7		5.6		78.5
Total fixed maturities	$	5.3	$	712.4	$	261.9	$	2,444.2	$	267.2	$	3,156.6

The Company views gross unrealized losses on fixed maturities as non-credit related and through its assessment of unrealized losses has determined that these securities will recover, allowing the Company to realize the anticipated long-term economic value. The Company currently does not intend to sell, nor does it expect to be required to sell these securities before recovery of their amortized cost. The Company employs a systematic methodology to evaluate declines in fair value below amortized cost for fixed maturity securities. In determining impairments, the Company evaluates several factors and circumstances, including the issuer’s overall financial condition; the issuer’s credit and financial strength ratings; the issuer’s financial performance, including earnings trends and asset quality; any specific events which may influence the operations of the issuer; the general outlook for market conditions in the industry or geographic region in which the issuer operates; and the degree to which the fair value of an issuer’s securities is below the Company’s amortized cost. The Company also considers any factors that might raise doubt about the issuer’s ability to make contractual payments as they come due and whether the Company expects to recover the entire amortized cost basis of the security.

For the three months ended March 31, 2026, the Company recognized impairment losses of $2.0 million, consisting of $1.5 million on mortgage loans and $0.5 million on fixed maturities. For the three months ended March 31, 2025, impairment losses were not significant.

At March 31, 2026 and December 31, 2025, the allowance for credit losses on mortgage loans was $8.5 million and $8.1 million, respectively. At March 31, 2026 and December 31, 2025, the allowance for credit losses on available-for-sale debt securities was not material.

The methodology and significant inputs used to measure the amount of credit losses were as follows:

Mortgage loans – the Company estimated losses by applying expected loss rates, which are based on historical data. Embedded in expected loss rates are mortgage risk ratings and risk factors associated with property type such as office, retail, lodging, multi-family and industrial. Risk ratings, based on property characteristics and metrics including the geographic market, are predominantly driven by estimates of loan-to-value and debt service coverage ratios. Ratings may be adjusted to reflect current conditions and to incorporate reasonable and supportable forecasts, such as volatility of cash flows and valuation.

Fixed maturities, Corporate bonds – the Company utilized a financial model that derives expected cash flows based on probability-of-default factors by credit rating and asset duration, and loss-given-default factors based on security type. These factors are based on historical data provided by an independent third-party rating agency. In addition, other qualitative market data relevant to the realizability of contractual cash flows may be considered, including current conditions and reasonable and supportable forecasts.