v3.26.1
Investment Securities (Tables)
 6 Months Ended
Jun. 30, 2026
Investments, Debt and Equity Securities [Abstract]  
Amortized Cost, Gross Unrealized Gains and Losses and Fair Value of Debt Securities Available for Sale
The amortized cost, gross unrealized gains and losses, and fair value of AFS debt securities at June 30, 2026 and December 31, 2025 were as follows: 
Amortized
Cost		Gross
Unrealized
Gains		Gross
Unrealized
Losses		Fair Value
(in thousands)
June 30, 2026
U.S. Treasury securities$251,614 $— $(24,616)$226,998 
U.S. government agency securities40,224 24 (1,549)38,699 
Obligations of states and political subdivisions:
Obligations of states and state agencies43,331 — (681)42,650 
Municipal bonds184,575 3 (29,874)154,704 
Total obligations of states and political subdivisions227,906 3 (30,555)197,354 
Residential mortgage-backed securities3,653,256 14,329 (77,885)3,589,700 
Corporate and other debt securities244,585 2,036 (7,224)239,397 
Total $4,417,585 $16,392 $(141,829)$4,292,148 
December 31, 2025
U.S. Treasury securities$250,494 $226 $(22,233)$228,487 
U.S. government agency securities41,026 35 (1,117)39,944 
Obligations of states and political subdivisions:
Obligations of states and state agencies44,079 — (646)43,433 
Municipal bonds181,883 1 (31,937)149,947 
Total obligations of states and political subdivisions225,962 1 (32,583)193,380 
Residential mortgage-backed securities3,541,284 36,238 (63,444)3,514,078 
Corporate and other debt securities231,876 1,781 (7,328)226,329 
Total$4,290,642 $38,281 $(126,705)$4,202,218 
Age of Unrealized Losses and Fair Value of Related Available for Sale Debt Securities
The age of unrealized losses and fair value of the related AFS debt securities at June 30, 2026 and December 31, 2025 were as follows: 
Less than 12 MonthsMore than 12 MonthsTotal
Fair
Value		Unrealized
Losses		Fair
Value		Unrealized
Losses		Fair
Value		Unrealized
Losses
(in thousands)
June 30, 2026
U.S. Treasury securities$98,582 $(1,445)$128,416 $(23,171)$226,998 $(24,616)
U.S. government agency securities17,848 (133)19,717 (1,416)37,565 (1,549)
Obligations of states and political subdivisions:
Obligations of states and state agencies
— — 5,180 (681)5,180 (681)
Municipal bonds1,685 (25)144,755 (29,849)146,440 (29,874)
Total obligations of states and political subdivisions
1,685 (25)149,935 (30,530)151,620 (30,555)
Residential mortgage-backed securities1,344,626 (13,743)468,565 (64,142)1,813,191 (77,885)
Corporate and other debt securities45,218 (532)122,893 (6,692)168,111 (7,224)
Total$1,507,959 $(15,878)$889,526 $(125,951)$2,397,485 $(141,829)
December 31, 2025
U.S. Treasury securities$— $— $128,232 $(22,233)$128,232 $(22,233)
U.S. government agency securities— — 20,754 (1,117)20,754 (1,117)
Obligations of states and political subdivisions:
Obligations of states and state agencies
— — 5,453 (646)5,453 (646)
Municipal bonds— — 141,083 (31,937)141,083 (31,937)
Total obligations of states and political subdivisions
— — 146,536 (32,583)146,536 (32,583)
Residential mortgage-backed securities118,263 (234)650,985 (63,210)769,248 (63,444)
Corporate and other debt securities12,741 (9)132,307 (7,319)145,048 (7,328)
Total$131,004 $(243)$1,078,814 $(126,462)$1,209,818 $(126,705)
Contractual Maturities of Debt Securities Available for Sale
The contractual maturities of AFS debt securities at June 30, 2026 are set forth in the following table. Contractual maturities may differ from actual maturities as borrowers may have the right to call or repay obligations with or without call or prepayment penalties. Residential mortgage-backed securities are not included in the maturity categories in the following maturity summary as actual maturities may differ from contractual maturities because the underlying mortgages may be called or prepaid without penalties.
June 30, 2026
Amortized
Cost		Fair
Value
(in thousands)
Due in one year$5,970 $5,941 
Due after one year through five years247,676 241,442 
Due after five years through ten years238,772 233,405 
Due after ten years271,911 221,660 
Residential mortgage-backed securities3,653,256 3,589,700 
Total $4,417,585 $4,292,148 
Amortized Cost, Gross Unrealized Gains and Losses and Fair Value of Debt Securities Held to Maturity
The amortized cost, gross unrealized gains and losses and fair value of HTM debt securities at June 30, 2026 and December 31, 2025 were as follows: 
Amortized
Cost		Gross
Unrealized
Gains		Gross
Unrealized
Losses		Fair ValueAllowance for Credit LossesNet Carrying Value
(in thousands)
June 30, 2026
U.S. government agency securities$290,828 $24 $(42,066)$248,786 $— $290,828 
Obligations of states and political subdivisions:
Obligations of states and state agencies57,749 374 (3,438)54,685 1 57,748 
Municipal bonds322,964 38 (19,942)303,060 200 322,764 
Total obligations of states and political subdivisions380,713 412 (23,380)357,745 201 380,512 
Residential mortgage-backed securities2,973,477 5,438 (324,397)2,654,518 — 2,973,477 
Trust preferred securities36,115 — (4,395)31,720 410 35,705 
Corporate and other debt securities76,811 4 (1,234)75,581 133 76,678 
Total $3,757,944 $5,878 $(395,472)$3,368,350 $744 $3,757,200 
December 31, 2025
U.S. government agency securities$292,269 $19 $(39,226)$253,062 $— $292,269 
Obligations of states and political subdivisions:
Obligations of states and state agencies
60,801 504 (3,293)58,012 2 60,799 
Municipal bonds293,074 43 (17,295)275,822 134 292,940 
Total obligations of states and political subdivisions353,875 547 (20,588)333,834 136 353,739 
Residential mortgage-backed securities2,732,752 11,050 (311,815)2,431,987 — 2,732,752 
Trust preferred securities36,103 — (5,414)30,689 425 35,678 
Corporate and other debt securities81,572 — (1,541)80,031 173 81,399 
Total $3,496,571 $11,616 $(378,584)$3,129,603 $734 $3,495,837 
Age of Unrealized Losses and Fair Value of Related Debt Securities Held to Maturity
The age of unrealized losses and fair value of related HTM debt securities at June 30, 2026 and December 31, 2025 were as follows: 
Less than 12 MonthsMore than 12 MonthsTotal
Fair ValueUnrealized
Losses		Fair ValueUnrealized
Losses		Fair ValueUnrealized
Losses
(in thousands)
June 30, 2026
U.S. government agency securities$— $— $232,530 $(42,066)$232,530 $(42,066)
Obligations of states and political subdivisions:
Obligations of states and state agencies9,178 (133)30,021 (3,305)39,199 (3,438)
Municipal bonds55,956 (5,944)143,223 (13,998)199,179 (19,942)
Total obligations of states and political subdivisions
65,134 (6,077)173,244 (17,303)238,378 (23,380)
Residential mortgage-backed securities
556,551 (6,848)1,721,951 (317,549)2,278,502 (324,397)
Trust preferred securities— — 31,721 (4,395)31,721 (4,395)
Corporate and other debt securities— — 28,077 (1,234)28,077 (1,234)
Total$621,685 $(12,925)$2,187,523 $(382,547)$2,809,208 $(395,472)
December 31, 2025
U.S. government agency securities$— $— $235,027 $(39,226)$235,027 $(39,226)
Obligations of states and political subdivisions:
Obligations of states and state agencies8,974 (161)32,537 (3,132)41,511 (3,293)
Municipal bonds18,237 (1,777)176,687 (15,518)194,924 (17,295)
Total obligations of states and political subdivisions
27,211 (1,938)209,224 (18,650)236,435 (20,588)
Residential mortgage-backed securities
23,866 (152)1,837,989 (311,663)1,861,855 (311,815)
Trust preferred securities— — 30,689 (5,414)30,689 (5,414)
Corporate and other debt securities
10,471 (29)64,560 (1,512)75,031 (1,541)
Total$61,548 $(2,119)$2,377,489 $(376,465)$2,439,037 $(378,584)
Contractual Maturities of Debt Securities Held to Maturity
The contractual maturities of investments in HTM debt securities at June 30, 2026 are set forth in the table below. Contractual maturities may differ from actual maturities as borrowers may have the right to call or repay obligations with or without call or prepayment penalties. Residential mortgage-backed securities are not included in the maturity categories in the following maturity summary as actual maturities may differ from contractual maturities because the underlying mortgages may be called or prepaid without penalties.
June 30, 2026
Amortized
Cost		Fair
Value
(in thousands)
Due in one year$63,671 $63,663 
Due after one year through five years62,696 61,800 
Due after five years through ten years171,687 163,482 
Due after ten years486,413 424,887 
Residential mortgage-backed securities2,973,477 2,654,518 
Total$3,757,944 $3,368,350 
Amortized Cost of Debt Securities Held to Maturity by External Credit Rating The following table summarizes the amortized cost of HTM debt securities by external credit rating at June 30, 2026 and December 31, 2025.
AAA/AA/A RatedBBB ratedNon-ratedTotal
(in thousands)
June 30, 2026
U.S. government agency securities$290,828 $— $— $290,828 
Obligations of states and political subdivisions:
Obligations of states and state agencies44,905 — 12,844 57,749 
Municipal bonds230,942 — 92,022 322,964 
Total obligations of states and political subdivisions275,847 — 104,866 380,713 
Residential mortgage-backed securities2,973,477 — — 2,973,477 
Trust preferred securities— — 36,115 36,115 
Corporate and other debt securities— — 76,811 76,811 
Total $3,540,152 $— $217,792 $3,757,944 
December 31, 2025
U.S. government agency securities$292,269 $— $— $292,269 
Obligations of states and political subdivisions:
Obligations of states and state agencies47,458 — 13,343 60,801 
Municipal bonds239,905 — 53,169 293,074 
Total obligations of states and political subdivisions287,363 — 66,512 353,875 
Residential mortgage-backed securities2,732,752 — — 2,732,752 
Trust preferred securities— — 36,103 36,103 
Corporate and other debt securities— 3,000 78,572 81,572 
Total$3,312,384 $3,000 $181,187 $3,496,571 
Debt Securities, Held-to-Maturity, Allowance for Credit Loss
The following table details the activity in the allowance for credit losses for HTM securities for the three and six months ended June 30, 2026 and 2025: 
Three Months Ended
June 30,		Six Months Ended
June 30,
2026202520262025
(in thousands)
Beginning balance$746 $633 $734 $647 
(Credit) provision for credit losses(2)4 10 (10)
Ending balance$744 $637 $744 $637