v3.26.1
Investment Securities
6 Months Ended
Jun. 30, 2026
Investments, Debt and Equity Securities [Abstract]  
Investment Securities Investment Securities
The amortized cost, estimated fair values and allowance for credit losses of investments in debt securities are summarized in the following tables:
June 30, 2026
(in thousands)Amortized
Cost
Gross
Unrealized
Gains
Gross
Unrealized
Losses
Estimated
Fair
Value
Debt Securities Available for Sale
Obligations of U.S. government agencies$1,217,068 $339 $(120,196)$1,097,211 
Obligations of states and political subdivisions239,510 72 (20,446)219,136 
Corporate bonds999 — (10)989 
Asset backed securities246,104 159 (948)245,315 
Non-agency collateralized mortgage obligations153,671 — (20,653)133,018 
Total debt securities available for sale$1,857,352 $570 $(162,253)$1,695,669 
Debt Securities Held to Maturity
Obligations of U.S. government agencies$79,225 $$(4,056)75,170 
Obligations of states and political subdivisions1,564 — (19)1,545 
Total debt securities held to maturity$80,789 $$(4,075)$76,715 

December 31, 2025
(in thousands)Amortized
Cost
Gross
Unrealized
Gains
Gross
Unrealized
Losses
Estimated
Fair
Value
Debt Securities Available for Sale
Obligations of U.S. government agencies$1,174,813 $1,600 $(112,385)$1,064,028 
Obligations of states and political subdivisions240,199 110 (19,623)220,686 
Corporate bonds4,981 (26)4,958 
Asset backed securities270,817 131 (1,428)269,520 
Non-agency collateralized mortgage obligations192,602 209 (20,072)172,739 
Total debt securities available for sale$1,883,412 $2,053 $(153,534)$1,731,931 
Debt Securities Held to Maturity
Obligations of U.S. government agencies$88,980 $$(3,552)$85,433 
Obligations of states and political subdivisions1,564 — (10)1,554 
Total debt securities held to maturity$90,544 $$(3,562)$86,987 
Proceeds from the sale or call of available for sale investment securities totaled $1.5 million during the three months ended June 30, 2026. with no gross realized gains or losses. Proceeds from the sale or call of available for sale investment securities totaled $0.7 million for the three months ended June 30, 2025, which resulted in gross realized gains of $4.0 thousand. Proceeds from the sale or call of available for sale investment securities totaled $4.5 million and $30.7 million for the six months ended June 30, 2026 and 2025, respectively, resulting in gross realized gains of $17.0 thousand and $1.1 million, respectively.
Investment securities with an aggregate carrying value of $792.7 million and $839.6 million at June 30, 2026 and December 31, 2025, respectively, were pledged as collateral for specific borrowings, lines of credit or local agency deposits.
The amortized cost and estimated fair value of debt securities at June 30, 2026 by contractual maturity are shown below. Actual maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. At June 30, 2026, obligations of the U.S. government and agencies with a cost basis totaling $1.2 billion consist almost entirely of residential real estate mortgage-backed securities whose contractual maturity, or principal repayment, will follow the repayment of the underlying mortgages. For purposes of the following table, the entire outstanding balance of these mortgage-backed securities issued by the U.S. government and agencies is categorized based on final maturity date. At June 30, 2026, the Company estimates the average remaining life of these mortgage-backed securities issued by U.S. government corporations and agencies to be approximately 5.7 years. Average remaining life is defined as the time span after which the principal balance has been reduced by half.
As of June 30, 2026, the contractual final maturity for available for sale and held to maturity investment securities is as follows:
Debt SecuritiesAvailable for SaleHeld to Maturity
(in thousands)Amortized
Cost
Estimated
Fair Value
Amortized
Cost
Estimated
Fair Value
Due in one year$3,317 $3,298 $17 $17 
Due after one year through five years94,117 90,150 2,584 2,537 
Due after five years through ten years236,030 215,993 77,438 73,446 
Due after ten years1,523,888 1,386,228 750 715 
Totals$1,857,352 $1,695,669 $80,789 $76,715 
Based on an evaluation of available information including security type, counterparty credit quality, past events, current conditions, and reasonable and supportable forecasts that are relevant to collectability of cash flows, as of June 30, 2026, the Company has concluded that it expects to receive all contractual cash flows from each security held in its AFS and HTM debt securities portfolio. There was no allowance for credit losses related to investment securities as of June 30, 2026 or December 31, 2025.
Gross unrealized losses on debt securities and the fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, were as follows:
June 30, 2026:Less than 12 months12 months or moreTotal
(in thousands)Fair
Value
Unrealized
Loss
Fair
Value
Unrealized
Loss
Fair
Value
Unrealized
Loss
Debt Securities Available for Sale
Obligations of U.S. government agencies$182,391 $(3,129)$857,482 $(117,067)$1,039,873 $(120,196)
Obligations of states and political subdivisions21,882 (301)185,569 (20,145)207,451 (20,446)
Corporate bonds988 (10)— — 988 (10)
Asset backed securities21,407 (44)64,336 (904)85,743 (948)
Non-agency collateralized mortgage obligations10,366 (51)122,652 (20,602)133,018 (20,653)
Total debt securities available for sale$237,034 $(3,535)$1,230,039 $(158,718)$1,467,073 $(162,253)
Debt Securities Held to Maturity
Obligations of U.S. government agencies$— $— $75,090 $(4,056)$75,090 $(4,056)
Obligations of states and political subdivisions1,545 (19)— — 1,545 (19)
Total debt securities held to maturity$1,545 $(19)$75,090 $(4,056)$76,635 $(4,075)
The following securities had unrealized losses as of June 30, 2026:
Obligations of U.S. government corporations and agencies included 161 debt securities with aggregate depreciation of 10.4% from the Company’s amortized cost basis.
Obligations of states and political subdivisions included 142 debt securities with aggregate depreciation of 9.0% from the Company’s amortized cost basis.
Corporate bonds included 2 debt securities with aggregate depreciation of 1.1% from the Company’s amortized cost basis.
Asset backed securities included 18 debt securities with aggregate depreciation of 1.1% from the Company’s amortized cost basis.
Non-agency collateralized mortgage obligations included 14 debt securities with aggregate depreciation of 13.4% from the Company’s amortized cost basis.
Based on an evaluation of available information including security type, counterparty credit quality, past events, current conditions, and reasonable and supportable forecasts that are relevant to collectability of cash flows, as of June 30, 2026, the Company has concluded that it expects to receive all contractual cash flows from each security held in its AFS and HTM debt securities portfolio. As such, the unrealized losses on these securities were caused by the changes in market interest rates or the widening of market spreads subsequent to the initial purchase of these securities and are not due to the underlying credit of the issuers.
December 31, 2025:Less than 12 months12 months or moreTotal
(in thousands)Fair
Value
Unrealized
Loss
Fair
Value
Unrealized
Loss
Fair
Value
Unrealized
Loss
Debt Securities Available for Sale
Obligations of U.S. government agencies$39,263 $(133)$916,500 $(112,252)$955,763 $(112,385)
Obligations of states and political subdivisions2,874 (106)201,382 (19,517)204,256 (19,623)
Corporate bonds495 (5)2,229 (21)2,724 (26)
Asset backed securities94,965 (161)70,084 (1,267)165,049 (1,428)
Non-agency collateralized mortgage obligations10,524 (1)131,873 (20,071)142,397 (20,072)
Total debt securities available for sale$148,121 $(406)$1,322,068 $(153,128)$1,470,189 $(153,534)
Debt Securities Held to Maturity
Obligations of U.S. government agencies$— $— $85,273 $(3,552)$85,273 $(3,552)
Obligations of states and political subdivisions— — 1,555 (10)1,555 (10)
Total debt securities held to maturity$— $— $86,828 $(3,562)$86,828 $(3,562)
The Company monitors credit quality of debt securities held-to-maturity through the use of credit ratings. The Company monitors the credit rating on a monthly basis. The following table summarizes the amortized cost of debt securities held-to-maturity at the dates indicated, aggregated by credit quality indicator:
June 30, 2026December 31, 2025
(in thousands)
AAA/AA/ABBB/BB/BAAA/AA/ABBB/BB/B
Obligations of U.S. government agencies$79,225 $— $88,980 $— 
Obligations of states and political subdivisions1,564 — 1,564 — 
Total debt securities held to maturity$80,789 $— $90,544 $—