As of March 31, 2025, the Company had $2.88 billion and $314.0 million in available for sale debt securities and held to maturity debt securities, respectively. Many factors, including lack of liquidity in the secondary market for certain securities, variations in pricing information, changes in interest rates, regulatory actions, changes in the business environment or any changes in the competitive marketplace, could have an adverse effect on the Company’s investment portfolio.

The following tables present the amortized cost, gross unrealized gains, gross unrealized losses and the fair value for available for sale debt securities as of March 31, 2025 and December 31, 2024 (in thousands):


	March 31, 2025
	Amortized cost		Gross unrealized gains	Gross unrealized losses	Fair value

U.S. Treasury obligations	$	330,547	339	(14,574)	316,312
Government-agency obligations	48,309		1,187	(167)	49,329
Mortgage-backed securities	2,399,880		8,690	(152,732)	2,255,838
Asset-backed securities	45,974		619	(207)	46,386
State and municipal obligations	125,239		437	(10,279)	115,397
Corporate obligations	93,229		4,877	(2,583)	95,523

	$	3,043,178	16,149	(180,542)	2,878,785


	December 31, 2024
	Amortized cost		Gross unrealized gains	Gross unrealized losses	Fair value

U.S. Treasury obligations	$	348,621	317	(18,340)	330,598
Government-agency obligations	105,965		1,461	(191)	107,235
Mortgage-backed securities	2,243,725		4,982	(186,548)	2,062,159
Asset-backed securities	47,203		645	(285)	47,563
State and municipal obligations	126,766		243	(10,092)	116,917
Corporate obligations	103,415		3,958	(2,930)	104,443

	$	2,975,695	11,606	(218,386)	2,768,915

Accrued interest on available for sale debt securities, which is excluded from the amortized cost, totaled $10.1 million and $9.7 million as of March 31, 2025 and December 31, 2024, respectively, and is presented within total accrued interest receivable on the Consolidated Statements of Financial Condition.

The amortized cost and fair value of available for sale debt securities as of March 31, 2025, by contractual maturity, are shown below (in thousands). Expected maturities may differ from contractual maturities due to prepayment or early call privileges of the issuer.


	March 31, 2025
	Amortized cost		Fair value
Due in one year or less	$	67,891	67,545
Due after one year through five years	303,663		290,043
Due after five years through ten years	111,816		111,182
Due after ten years	70,591		63,419
	$	553,961	532,189

Investments which pay principal on a periodic basis, and are primarily related to mortgage-backed securities totaling $2.49 billion at amortized cost and $2.35 billion at fair value are excluded from the table above as their expected lives are likely to be shorter than the contractual maturity date due to principal prepayments.

For the three months ended March 31, 2025 proceeds from sales on securities in the available for sale debt portfolio totaled $1.7 million with gross gains of $87,000 and no losses recognized, while calls from securities from the available for sale debt portfolio totaled $9.6 million with no gross gains and no losses recognized. For March 31, 2024, no securities were sold or called from the available for sale debt securities portfolio.

The number of available for sale debt securities in an unrealized loss position as of March 31, 2025 totaled 502, compared with 646 as of December 31, 2024. The decrease in the number of securities in an unrealized loss position as of March 31, 2025 was due to lower current market interest rates compared to rates as of December 31, 2024. All securities in an unrealized loss position were investment grade as of March 31, 2025.

The following tables present the amortized cost, gross unrealized gains, gross unrealized losses and the estimated fair value for held to maturity debt securities as of March 31, 2025 and December 31, 2024 (in thousands):


	March 31, 2025
	Amortized cost		Gross unrealized gains	Gross unrealized losses	Fair value

Government-agency obligations	$	9,999	—	(198)	9,801

State and municipal obligations	297,966		14	(12,540)	285,440
Corporate obligations	6,057		—	(108)	5,949
	$	314,022	14	(12,846)	301,190


	December 31, 2024
	Amortized cost		Gross unrealized gains	Gross unrealized losses	Fair value

Government-agency obligations	$	9,999	—	(292)	9,707

State and municipal obligations	311,118		689	(14,133)	297,674
Corporate obligations	6,520		—	(168)	6,352
	$	327,637	689	(14,593)	313,733

Accrued interest on held to maturity debt securities, which is excluded from the amortized cost, totaled $2.3 million and $2.9 million as of March 31, 2025 and December 31, 2024, respectively, and is presented within total accrued interest receivable on the Consolidated Statements of Financial Condition.

The Company generally purchases securities for long-term investment purposes, and differences between amortized cost and fair value may fluctuate during the investment period. There were no sales of securities from the held to maturity debt securities portfolio for the three months ended March 31, 2025 and 2024. For the three months ended March 31, 2025, proceeds from calls of securities in the held to maturity debt securities portfolio totaled $5.0 million, with no gross gains and no gross losses. For the three months ended March 31, 2024, proceeds from calls of securities in the held to maturity debt securities portfolio totaled $1.2 million with no gross gains and gross losses of $1,200.

The amortized cost and fair value of investment securities in the held to maturity debt securities portfolio as of March 31, 2025 by contractual maturity are shown below (in thousands). Expected maturities may differ from contractual maturities due to prepayment or early call privileges of the issuer.


	March 31, 2025
	Amortized cost		Fair value
Due in one year or less	$	48,529	48,232
Due after one year through five years	160,896		158,405
Due after five years through ten years	87,360		81,152
Due after ten years	17,237		13,401
	$	314,022	301,190

The allowance for credit losses on held to maturity debt securities as of March 31, 2025 and December 31, 2024 was $17,000 and $14,000, respectively, and are excluded from amortized cost in the table above.

The number of held to maturity debt securities in an unrealized loss position as of March 31, 2025 totaled 479, compared with 512 as of December 31, 2024. The decrease in the number of securities in an unrealized loss position as of March 31, 2025, was due to lower current market interest rates compared to rates as of December 31, 2024.

Management measures expected credit losses on held to maturity debt securities on a collective basis by security type. Management classifies the held to maturity debt securities portfolio into the following security types:

All of the agency obligations held by the Company are issued by U.S. government entities and agencies. These securities are either explicitly or implicitly guaranteed by the U.S. government, are highly rated by major rating agencies and have a long history of no credit losses. The majority of the state and municipal and corporate obligations carry credit ratings from the rating agencies as of March 31, 2025, that were no lower than an A rating and the Company had no securities rated BBB or worse by Moody’s Ratings ("Moody's").

Credit Quality Indicators. The following table provides the amortized cost of held to maturity debt securities by credit rating as of March 31, 2025 and December 31, 2024 (in thousands):


	March 31, 2025
Total Portfolio	AAA		AA	A	BBB	Not Rated	Total

Government-agency obligations	9,999		—	—	—	—	9,999

State and municipal obligations	44,785		223,348	24,938	—	4,895	297,966
Corporate obligations	500		2,005	3,527	—	25	6,057
	$	55,284	225,353	28,465	—	4,920	314,022

	December 31, 2024
Total Portfolio	AAA		AA	A	BBB	Not Rated	Total

Government-agency obligations	$	9,999	—	—	—	—	9,999

State and municipal obligations	44,821		234,212	28,735	—	3,350	311,118
Corporate obligations	501		2,013	3,981	—	25	6,520
	$	55,321	236,225	32,716	—	3,375	327,637

Credit quality indicators are metrics that provide information regarding the relative credit risk of debt securities. As of March 31, 2025, the held to maturity debt securities portfolio was comprised of 18% rated AAA, 72% rated AA, 9% rated A, and less than 1% either below an A rating or not rated by Moody’s or Standard and Poor’s. Securities not explicitly rated, such as U.S. Government mortgage-backed securities, were grouped where possible under the credit rating of the issuer of the security.