
	September 30, 2023
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Available-for-Sale Debt Securities
U.S. Treasury securities and obligations of U.S. government agencies	$	39,388	$	2	$	(954)	$	38,436
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	1,593,306		58		(266,725)		1,326,639
Private mortgage-backed securities and collateralized mortgage obligations	139,089		25		(13,927)		125,187
Collateralized loan obligations	307,664		—		(3,496)		304,168
Obligations of state and political subdivisions	21,768		—		(2,116)		19,652
Other debt securities	27,293		596		(126)		27,763
Totals	$	2,128,508	$	681	$	(287,344)	$	1,841,845

Held-to-Maturity Debt Securities
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	$	691,404	$	—	$	(154,186)	$	537,218
Totals	$	691,404	$	—	$	(154,186)	$	537,218


	December 31, 2022
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Available-for-Sale Debt Securities
U.S. Treasury securities and obligations of U.S. government agencies	$	13,813	$	173	$	(339)	$	13,647
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	1,561,197		539		(223,083)		1,338,653
Private mortgage-backed securities and collateralized mortgage obligations	179,148		70		(12,831)		166,387
Collateralized loan obligations	313,155		—		(10,251)		302,904
Obligations of state and political subdivisions	29,350		122		(1,731)		27,741
Other debt securities	22,640		197		(427)		22,410
Totals	$	2,119,303	$	1,101	$	(248,662)	$	1,871,742

Held-to-Maturity Debt Securities
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	$	747,408	$	64	$	(129,731)	$	617,741


Totals	$	747,408	$	64	$	(129,731)	$	617,741

During the three months ended March 31, 2023, debt securities with a fair value of $22.1 million obtained in the acquisition of Professional Holding Corp. (“Professional”) were sold. No gain or loss was recognized on the sale. There were $8.4 million in other sales of securities during the three months ended March 31, 2023, with gross gains of $24 thousand and gross losses of $19 thousand. There were no other sales of securities during the three and nine months ended September 30, 2023. During the three months ended March 31, 2022, securities with a fair value of $26.0 million obtained in the acquisition of Business Bank of Florida Corp. were immediately sold. No gain or loss was recognized on the sale. There were no other sales of securities during the three and nine months ended September 30, 2022. Included in “Securities losses, net” are decreases of $0.4 million and $0.5 million for the three and nine months ended September 30, 2023, respectively, and decreases of $0.4 million and $1.1 million for the three and nine months ended September 30, 2022, respectively, in the value of investments in mutual funds that invest in CRA-qualified debt securities.

The amortized cost and fair value of securities as of September 30, 2023, by contractual maturity, are shown below. Expected maturities will differ from contractual maturities because prepayments of the underlying collateral for these securities may occur, due to the right to call or repay obligations with or without call or prepayment penalties. Securities not due at a single maturity date are shown separately.


	September 30, 2023
	Held-to-Maturity				Available-for-Sale
(In thousands)	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Due in less than one year	$	—	$	—	$	6,157	$	6,083
Due after one year through five years	—		—		11,621		11,365
Due after five years through ten years	—		—		11,075		10,938
Due after ten years	—		—		32,303		29,702
	—		—		61,156		58,088

Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	691,404		537,218		1,593,306		1,326,639
Private mortgage-backed securities and collateralized mortgage obligations	—		—		139,089		125,187
Collateralized loan obligations	—		—		307,664		304,168
Other debt securities	—		—		27,293		27,763
Totals	$	691,404	$	537,218	$	2,128,508	$	1,841,845

The estimated fair value of a security is determined based on market quotations when available or, if not available, by using quoted market prices for similar securities, pricing models, or discounted cash flow analyses, or using observable market data. The tables below indicate the fair value of available-for-sale debt securities with unrealized losses for which no allowance for credit losses has been recorded.


	September 30, 2023
	Less Than 12 Months				12 Months or Longer				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 agencies	$	33,881	$	(467)	$	3,569	$	(487)	$	37,450	$	(954)
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	174,339		(18,084)		1,142,859		(248,641)		1,317,198		(266,725)
Private mortgage-backed securities and collateralized mortgage obligations	4,814		(84)		119,348		(13,843)		124,162		(13,927)
Collateralized loan obligations	59,580		(730)		244,588		(2,766)		304,168		(3,496)
Obligations of state and political subdivisions	8,394		(296)		11,258		(1,820)		19,652		(2,116)
Other debt securities	10,765		(126)		—		—		10,765		(126)
Totals	$	291,773	$	(19,787)	$	1,521,622	$	(267,557)	$	1,813,395	$	(287,344)


	December 31, 2022
	Less Than 12 Months				12 Months or Longer				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 agencies	$	3,788	$	(328)	$	249	$	(11)	$	4,037	$	(339)
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	646,651		(54,956)		667,520		(168,127)		1,314,171		(223,083)
Private mortgage-backed securities and collateralized mortgage obligations	130,488		(8,255)		25,234		(4,576)		155,722		(12,831)
Collateralized loan obligations	242,370		(8,343)		60,534		(1,908)		302,904		(10,251)
Obligations of state and political subdivisions	23,804		(1,656)		425		(75)		24,229		(1,731)
Other debt securities	11,459		(427)		—		—		11,459		(427)
Totals	$	1,058,560	$	(73,965)	$	753,962	$	(174,697)	$	1,812,522	$	(248,662)

At September 30, 2023, the Company had unrealized losses of $266.7 million on mortgage-backed securities and collateralized mortgage obligations issued by government-sponsored entities having a fair value of $1.3 billion. These securities are either explicitly or implicitly guaranteed by the U.S. government and have a long history of no credit losses. The implied government guarantee of principal and interest payments and the high credit rating of the portfolio provide a sufficient basis for the current expectation that there is no risk of loss if default were to occur. Based on the assessment of all relevant factors, the Company believes that the unrealized loss positions on these debt securities are a function of changes in investment spreads and interest rate movements and not changes in credit quality, and expects to recover the entire amortized cost basis of these securities. Therefore, on September 30, 2023, no allowance for credit losses has been recorded.

At September 30, 2023, the Company had $13.9 million of unrealized losses on private-label residential and commercial mortgage-backed securities and collateralized mortgage obligations having a fair value of $124.2 million. The securities have a weighted average credit support of 22%. Based on the assessment of all relevant factors, the Company believes that the unrealized loss positions on these debt securities are a function of changes in investment spreads and interest rate movements and not changes in credit quality, and expects to recover the entire amortized cost basis of these securities. Therefore, at September 30, 2023, no allowance for credit losses has been recorded.

At September 30, 2023, the Company had $3.5 million of unrealized losses in floating rate collateralized loan obligations (“CLOs”) having a fair value of $304.2 million. CLOs are special purpose vehicles and those in which the Company has invested are nearly all first-lien, broadly syndicated corporate loans across a diversified band of industries while providing support to senior tranche investors. As of September 30, 2023, all positions held by the Company are in AAA and AA tranches, with weighted average credit support of 38% and 25%, respectively. The Company evaluates the securities for potential credit losses by modeling expected loan-level defaults, recoveries, and prepayments for each CLO security. Based on the assessment of all relevant factors, the Company believes that the unrealized loss positions on these debt securities are a function of changes in investment spreads and interest rate movements and not changes in credit quality, and expects to recover the entire amortized cost basis of these securities. Therefore, at September 30, 2023, no allowance for credit losses has been recorded.

At September 30, 2023, the Company had $2.1 million of unrealized losses on municipal securities having a fair value of $19.7 million. These securities are highly rated issuances of state or local municipalities, all of which are continuing to make timely contractual payments. Based on the assessment of all relevant factors, the Company believes that the unrealized loss positions on these debt securities are a function of changes in investment spreads and interest rate movements and not changes in credit quality, and expects to recover the entire amortized cost basis of these securities. As a result, as of September 30, 2023, no allowance for credit losses has been recorded.

All held-to-maturity (“HTM”) debt securities are issued by government-sponsored entities, which are either explicitly or implicitly guaranteed by the U.S. government and have a long history of no credit losses. While the potential for default on these securities may be greater than zero, the long history with no credit losses, the implied government guarantee of principal and interest payments, and the high credit rating of the HTM portfolio provide sufficient basis for the current expectation that there is no risk of loss if default were to occur. As a result, as of September 30, 2023, no allowance for credit losses has been recorded. The Company has the intent and ability to hold these securities until maturity.