
December 31, 2025	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Available-for-Sale:
U.S. Treasury notes	$	246.5	$	—	$	(8.8)	$	237.7
State, county, and municipal securities	247.3		—		(27.2)		220.1
Obligations of U.S. government agencies	205.1		—		(4.2)		200.9
U.S. agency commercial mortgage-backed securities	891.7		1.1		(36.1)		856.7
U.S. agency residential mortgage-backed securities	1,834.4		4.4		(68.7)		1,770.1
U.S. agency collateralized mortgage obligations	986.1		1.4		(64.8)		922.7
Private mortgage-backed securities	193.9		—		(19.5)		174.4
Collateralized loan obligation	754.3		1.2		—		755.5
Corporate securities	158.7		—		(8.7)		150.0

Total	$	5,518.0	$	8.1	$	(238.0)	$	5,288.1


December 31, 2025	Amortized Cost(1)		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Held-to Maturity:

State, county, and municipal securities	$	173.2	$	0.2	$	(18.6)	$	154.8
Obligations of U.S. government agencies	462.3		—		(37.7)		424.6
U.S. agency commercial mortgage-backed securities	354.8		—		(18.8)		336.0
U.S. agency residential mortgage-backed securities	941.3		0.1		(84.7)		856.7
U.S. agency collateralized mortgage obligations	381.1		0.7		(46.4)		335.4
Corporate securities	29.9		—		(0.8)		29.1

Total	$	2,342.6	$	1.0	$	(207.0)	$	2,136.6
(1) Amortized cost presented above is net of an allowance for credit losses of $0.5 million and includes $5.9 million of unamortized gains and $13.7 million of unamortized losses related to the 2021 and 2022 transfer of securities from available-for-sale to held-to-maturity, respectively.


December 31, 2024	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Available-for-Sale:
U.S. Treasury notes	$	245.0	$	—	$	(18.1)	$	226.9
State, county, and municipal securities	252.0		—		(40.0)		212.0
Obligations of U.S. government agencies	224.1		—		(10.8)		213.3
U.S. agency commercial mortgage-backed securities	1,057.2		0.1		(74.5)		982.8
U.S. agency residential mortgage-backed securities	1,301.2		0.4		(125.8)		1,175.8
U.S. agency collateralized mortgage obligations	1,156.9		0.6		(106.6)		1,050.9
Private mortgage-backed securities	218.1		—		(27.6)		190.5
Collateralized loan obligation	770.7		1.3		—		772.0
Corporate securities	249.6		—		(16.7)		232.9

Total	$	5,474.8	$	2.4	$	(420.1)	$	5,057.1


December 31, 2024	Amortized Cost(1)		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Held-to Maturity:
U.S. Treasury notes	$	99.8	$	—	$	(0.4)	$	99.4
State, county, and municipal securities	176.3		0.2		(26.7)		149.8
Obligations of U.S. government agencies	470.1		—		(59.9)		410.2
U.S. agency commercial mortgage-backed securities	374.9		—		(33.4)		341.5
U.S. agency residential mortgage-backed securities	1,082.5		—		(140.7)		941.8
U.S. agency collateralized mortgage obligations	427.8		—		(66.1)		361.7
Corporate securities	57.0		—		(2.8)		54.2

Total	$	2,688.4	$	0.2	$	(330.0)	$	2,358.6
(1) Amortized cost presented above is net of an allowance for credit losses of $0.9 million and includes $8.0 million of unamortized gains and $15.9 million of unamortized losses related to the 2021 and 2022 transfer of securities from available-for-sale to held-to-maturity, respectively.

The following tables show the gross unrealized losses and fair values of available-for-sale investment securities and the length of time individual investment securities have been in an unrealized loss position as of December 31, 2025 and 2024.


	Less than 12 Months				12 Months or More				Total
December 31, 2025	Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses
Available-for-Sale:
U.S. Treasury notes	$	—	$	—	$	237.7	$	(8.8)	$	237.7	$	(8.8)
State, county, and municipal securities	—		—		210.4		(27.2)		210.4		(27.2)
Obligations of U.S. government agencies	2.4		—		195.8		(4.2)		198.2		(4.2)
U.S. agency commercial mortgage-backed securities	1.3		—		821.6		(36.1)		822.9		(36.1)
U.S. agency residential mortgage-backed securities	254.4		(1.1)		956.5		(67.6)		1,210.9		(68.7)
U.S. agency collateralized mortgage obligations	—		—		869.9		(64.8)		869.9		(64.8)
Private mortgage-backed securities	—		—		174.3		(19.5)		174.3		(19.5)

Corporate securities	—		—		150.0		(8.7)		150.0		(8.7)

Total	$	258.1	$	(1.1)	$	3,616.2	$	(236.9)	$	3,874.3	$	(238.0)


	Less than 12 Months				12 Months or More				Total
December 31, 2024	Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses
Available-for-Sale:
U.S. Treasury notes	$	—	$	—	$	226.8	$	(18.1)	$	226.8	$	(18.1)
State, county, and municipal securities	—		—		210.1		(40.0)		210.1		(40.0)
Obligations of U.S. government agencies	3.6		—		206.2		(10.8)		209.8		(10.8)
U.S. agency commercial mortgage-backed securities	38.1		(0.4)		934.9		(74.1)		973.0		(74.5)
U.S. agency residential mortgage-backed securities	33.7		(1.5)		1,086.2		(124.3)		1,119.9		(125.8)
U.S. agency collateralized mortgage obligations	20.5		(0.3)		987.1		(106.3)		1,007.6		(106.6)
Private mortgage-backed securities	—		—		190.4		(27.6)		190.4		(27.6)
Collateralized loan obligation	10.0		—		—		—		10.0		—
Corporate securities	27.5		(0.5)		205.5		(16.2)		233.0		(16.7)

Total	$	133.4	$	(2.7)	$	4,047.2	$	(417.4)	$	4,180.6	$	(420.1)

The Company determines the allowance for credit losses on both available-for-sale and held-to-maturity investment securities by a discounted cash flow approach when needed, using each security’s effective interest rate at the time of purchase or upon acquisition. The allowance for credit losses for available-for-sale investment securities is measured as the amount by which an investment security’s amortized cost exceeds the net present value of expected future cash flows, however, the amount of credit losses is limited to the amount of a security’s unrealized loss. The allowance for credit loss on held-to-maturity investment securities is representative of current expected credit losses that management expects to be incurred over the life of the investment and established through a charge to provision for credit losses in current period earnings. For held-to-maturity investment securities, the Company has the intent and ability to hold these investment securities to maturity.

The investment securities portfolio primarily contains securities that are guaranteed by a sovereign entity or are generally considered to have non-credit related risks, such as interest rate risk or liquidity factors. The Company considers whether the securities are issued by the federal government or its agencies and whether downgrades by bond rating agencies have occurred.

As of December 31, 2025 and 2024, the Company had 633 and 670 individual available-for-sale investment securities, respectively, that were in an unrealized loss position, which was related primarily to fluctuations in current interest rates. As of December 31, 2025, the Company does not intend to sell nor is it more likely than not the Company will be required to sell any available-for-sale securities with unrealized losses.

On a quarterly basis, the Company refreshes the credit quality indicator of each held-to-maturity security. As of December 31, 2025 and 2024, the held-to-maturity portfolio is primarily composed of investment grade or better securities. The Company had a $0.5 million and a $0.9 million allowance for credit losses for held-to-maturity corporate and state, county, and municipal investment securities as of December 31, 2025 and 2024, respectively.

As of December 31, 2025 and 2024, the Company had $27.8 million and $29.6 million, respectively, of accrued interest receivable from investment securities on the consolidated balance sheets. Accrued interest receivable is presented as a separate line item on the consolidated balance sheets and is not included in the carrying value of our securities.

The following schedule represents the amortized cost of debt securities by contractual maturity except for maturities of mortgage-backed securities, which have been adjusted to reflect shorter maturities based upon estimated prepayments of principal.


	Available-for-Sale				Held-to-Maturity
December 31, 2025	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
Within one year	$	114.4	$	113.5	$	32.8	$	32.9
After one year but within five years	1,239.7		1,192.6		617.0		587.1
After five years but within ten years	944.6		877.5		273.2		249.8
After ten years	3,219.3		3,104.5		1,419.6		1,266.8
Total	$	5,518.0	$	5,288.1	$	2,342.6	$	2,136.6

As of December 31, 2025, the Company held investment securities callable within one year having amortized costs and estimated fair values of $603.6 million and $577.8 million, respectively. These investment securities are primarily included in the “after five year” categories in the table above.

As of December 31, 2025 and 2024, the Company had securities with carrying values of $2,983.6 million and $3,460.2 million, respectively, for investment securities pledged to secure public deposits, derivatives, and securities sold under repurchase agreements that had estimated fair values as of December 31, 2025 and 2024 of $2,781.2 million and $3,092.6 million, respectively. All securities sold under repurchase agreements are with clients and mature on the next banking day. The Company retains possession of the underlying securities sold under repurchase agreements.

As of December 31, 2025 and 2024, the Company held $106.3 million and $177.4 million, respectively, in equity securities primarily in a combination of Federal Reserve Bank and Federal Home Loan Bank (“FHLB”) stocks, which are restricted nonmarketable securities acquired to meet regulatory requirements and related to outstanding borrowings. These securities are carried at cost.