v3.26.3
Investment Securities (Tables)
 9 Months Ended
Sep. 30, 2026
Investments, Debt and Equity Securities [Abstract]  
Schedule of Securities Available for Sale
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 September 30, 2026 and December 31, 2025 (in thousands):
September 30, 2026
Amortized
cost		Gross
unrealized
gains		Gross
unrealized
losses		Fair
value
U.S. Treasury obligations$191,896 2 (6,556)185,342 
Government-agency obligations26,673 597 (64)27,206 
Mortgage-backed securities3,051,193 1,012 (233,760)2,818,445 
Asset-backed securities34,256 427 (207)34,476 
State and municipal obligations118,869 19 (14,985)103,903 
Corporate obligations112,318 4,973 (2,313)114,978 
$3,535,205 7,030 (257,885)3,284,350 
December 31, 2025
Amortized
cost		Gross
unrealized
gains		Gross
unrealized
losses		Fair
value
U.S. Treasury obligations$274,500 190 (7,946)266,744 
Government-agency obligations32,693 877 (31)33,539 
Mortgage-backed securities2,705,346 23,454 (116,453)2,612,347 
Asset-backed securities41,619 409 (267)41,761 
State and municipal obligations119,173 1,249 (7,423)112,999 
Corporate obligations93,498 5,429 (1,561)97,366 
$3,266,829 31,608 (133,681)3,164,756 
Schedule of Investment Securities Classified by Contractual Maturity
The amortized cost and fair value of available for sale debt securities as of September 30, 2026, 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.
September 30, 2026
Amortized
cost		Fair
value
Due in one year or less$97,786 97,143 
Due after one year through five years121,543 115,334 
Due after five years through ten years140,981 139,291 
Due after ten years62,773 52,455 
Securities without a contractual maturity (1)
3,112,122 2,880,127 
$3,535,205 3,284,350 
(1) Residential mortgage-backed securities, other asset-backed securities and government-agency obligations are not included in the maturity categories as actual maturities may differ from contractual maturities because the underlying loans may be called or prepaid without penalties.
The amortized cost and fair value of investment securities in the held to maturity debt securities portfolio as of September 30, 2026 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.
The amortized cost and fair value of held to maturity debt securities as of September 30, 2026 by contractual maturity, excluding allowances for credit losses of 22,000 as of September 30, 2026 are shown below (in thousands). Expected maturities may differ from contractual maturities due to prepayment or early call privileges of the issuer.
September 30, 2026
Amortized
cost		Fair
value
Due in one year or less$51,398 51,186 
Due after one year through five years142,485 137,440 
Due after five years through ten years60,143 50,746 
Due after ten years3,080 2,248 
$257,106 241,620 
Schedule of Gross Unrealized Losses and Estimated Fair Value of Available for Sale Debt Securities
The following table shows gross unrealized losses and estimated fair value of available for sale debt securities, aggregated by investment category and length of time that individual investment securities have been in a continuous loss position as of September 30, 2026 and December 31, 2025 (in thousands):
September 30, 2026
Less Than 12 months12 Months or MoreTotal
Fair
value
Unrealized Losses
Fair
value
Unrealized Losses
Fair
value
Unrealized Losses
Available-for-sale:
U.S. Treasury obligations$2,441 (3)172,927 (6,553)175,368 (6,556)
Government-agency obligations8,314 (64)— — 8,314 (64)
Mortgage-backed securities1,814,944 (87,350)863,356 (146,410)2,678,300 (233,760)
Asset-backed securities 9,254 (36)2,006 (171)11,260 (207)
State and municipal obligations41,237 (3,211)60,485 (11,774)101,722 (14,985)
Corporate obligations35,715 (1,285)19,189 (1,028)54,904 (2,313)
Total$1,911,905 (91,949)1,117,963 (165,936)3,029,868 (257,885)
December 31, 2025
Less Than 12 months12 Months or MoreTotal
Fair
value
Unrealized Losses
Fair
value
Unrealized Losses
Fair
value
Unrealized Losses
Available-for-sale:
U.S. Treasury obligations$— — 245,675 (7,946)245,675 (7,946)
Government-agency obligations8,541 (31)— — 8,541 (31)
Mortgage-backed securities133,316 (4,119)984,261 (112,334)1,117,577 (116,453)
Asset-backed securities 20,493 (129)1,605 (138)22,098 (267)
State and municipal obligations21,613 (665)53,173 (6,758)74,786 (7,423)
Corporate obligations8,994 (6)18,742 (1,555)27,736 (1,561)
Total$192,957 (4,949)1,303,456 (128,732)1,496,412 (133,681)
Schedule of Investment Securities Held to Maturity
The following tables present the amortized cost, gross unrealized gains, gross unrealized losses and the estimated fair value for held to maturity debt securities, excluding allowances for credit losses of $22,000 and $16,000, as of September 30, 2026 and December 31, 2025, respectively (in thousands):
September 30, 2026
Amortized
cost		Gross
unrealized
gains 		Gross
unrealized
losses 		Fair
value
State and municipal obligations257,106 — (15,486)241,620 
$257,106 — (15,486)241,620 
December 31, 2025
Amortized
cost		Gross
unrealized
gains 		Gross
unrealized
losses 		Fair
value
Government-agency obligations$3,400 — (22)3,378 
State and municipal obligations276,600 156 (7,045)269,711 
Corporate obligations2,143 — (14)2,129 
$282,143 156 (7,081)275,218 
Schedule of Amortized Cost of Held to Maturity Debt Securities by Credit Rating The following table provides the amortized cost of held to maturity debt securities by credit rating as of September 30, 2026 and December 31, 2025 (in thousands):
September 30, 2026
Total PortfolioAAAAAABBBNot RatedTotal
State and municipal obligations42,915 178,179 15,476 — 20,536 257,106 
$42,915 178,179 15,476 — 20,536 257,106 
December 31, 2025
Total PortfolioAAAAAABBBNot RatedTotal
Government-agency obligations$3,400 — — — — 3,400 
State and municipal obligations44,930 199,977 20,896 — 10,797 276,600 
Corporate obligations— 573 1,570 — — 2,143 
$48,330 200,550 22,466 — 10,797 282,143 
Schedule of Gross Unrealized Losses and Estimated Fair Value of Held to Maturity Debt Securities
The following table shows gross unrealized losses and estimated fair value of held to maturity debt securities, aggregated by investment category and length of time that individual investment securities have been in a continuous loss position as of September 30, 2026 and December 31, 2025 (in thousands):

September 30, 2026
Less Than 12 months12 Months or MoreTotal
Fair
value
Unrealized Losses
Fair
value
Unrealized Losses
Fair
value
Unrealized Losses
Held-to-maturity:
State and municipal obligations144,745 (4,291)76,430 (11,195)221,175 (15,486)
Total$144,745 (4,291)76,430 (11,195)221,175 (15,486)
December 31, 2025
Less Than 12 months12 Months or MoreTotal
Fair
value
Unrealized Losses
Fair
value
Unrealized Losses
Fair
value
Unrealized Losses
Held-to-maturity:
Government-agency obligations$— — 3,388 (22)3,388 (22)
State and municipal obligations3,353 (1)127,012 (7,044)130,365 (7,045)
Corporate obligations— — 2,129 (14)2,129 (14)
Total$3,353 (1)132,529 (7,080)135,882 (7,081)