XML 46 R35.htm IDEA: XBRL DOCUMENT v3.26.1
Securities (Tables)
 3 Months Ended
Mar. 31, 2026
Securities  
Schedule of amortized cost and fair value of investment securities held to maturity

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Gross

  ​ ​ ​

Gross

​

​

 

​

​

Amortized

​

Unrealized

​

Unrealized

​

Fair

 

(Dollars in thousands)

  ​ ​ ​

Cost

  ​ ​ ​

Gains

  ​ ​ ​

Losses

  ​ ​ ​

Value

 

March 31, 2026:

​

​

​

​

​

​

​

​

​

​

​

​

​

U.S. Government agencies

​

$

132,914

​

$

—

​

$

(16,892)

​

$

116,022

​

Residential mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

1,123,852

​

​

—

​

​

(181,274)

​

​

942,578

​

Residential collateralized mortgage-obligations issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

372,106

​

​

—

​

​

(58,553)

​

​

313,553

​

Commercial mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

332,619

​

​

—

​

​

(58,228)

​

​

274,391

​

Small Business Administration loan-backed securities

​

​

45,758

​

​

—

​

​

(8,164)

​

​

37,594

​

​

​

$

2,007,249

​

$

—

​

$

(323,111)

​

$

1,684,138

​

December 31, 2025:

​

​

​

​

​

​

​

​

​

​

​

​

​

U.S. Government agencies

​

$

132,913

​

$

—

​

$

(15,767)

​

$

117,146

​

Residential mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

1,153,024

​

​

—

​

​

(177,101)

​

​

975,923

​

Residential collateralized mortgage-obligations issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

379,107

​

​

—

​

​

(55,232)

​

​

323,875

​

Commercial mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

336,910

​

​

—

​

​

(58,332)

​

​

278,578

​

Small Business Administration loan-backed securities

​

​

46,076

​

​

—

​

​

(8,748)

​

​

37,328

​

​

​

$

2,048,030

​

$

—

​

$

(315,180)

​

$

1,732,850

​
Schedule of amortized cost and fair value of investment securities available for sale

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Gross

​

Gross

​

​

​

​

​

​

Amortized

​

Unrealized

​

Unrealized

​

Fair

 

(Dollars in thousands)

  ​ ​ ​

Cost

  ​ ​ ​

Gains

  ​ ​ ​

Losses

  ​ ​ ​

Value

 

March 31, 2026:

​

​

​

​

​

​

​

​

​

​

​

​

​

Residential mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

$

1,991,530

​

$

5,089

​

$

(147,521)

​

$

1,849,098

​

Residential collateralized mortgage-obligations issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

2,148,049

​

​

9,383

​

​

(52,877)

​

​

2,104,555

​

Commercial mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

1,047,410

​

​

1,545

​

​

(78,644)

​

​

970,311

​

State and municipal obligations

​

​

1,191,625

​

​

593

​

​

(151,023)

​

​

1,041,195

​

Small Business Administration loan-backed securities

​

​

567,569

​

​

464

​

​

(24,548)

​

​

543,485

​

Corporate securities

​

​

23,000

​

​

—

​

​

(1,296)

​

​

21,704

​

​

​

$

6,969,183

​

$

17,074

​

$

(455,909)

​

$

6,530,348

​

December 31, 2025:

​

​

​

​

​

​

​

​

​

​

​

​

​

Residential mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

$

1,826,307

​

$

10,108

​

$

(138,307)

​

$

1,698,108

​

Residential collateralized mortgage-obligations issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

2,208,710

​

​

23,979

​

​

(47,105)

​

​

2,185,584

​

Commercial mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

903,209

​

​

3,282

​

​

(74,042)

​

​

832,449

​

State and municipal obligations

​

​

1,141,377

​

​

1,252

​

​

(135,217)

​

​

1,007,412

​

Small Business Administration loan-backed securities

​

​

593,973

​

​

548

​

​

(26,088)

​

​

568,433

​

Corporate securities

​

​

23,000

​

​

—

​

​

(1,230)

​

​

21,770

​

​

​

$

6,696,576

​

$

39,169

​

$

(421,989)

​

$

6,313,756

​
Schedule of amortized cost and carrying value of other investment securities

​

​

​

​

​

​

​

​

Carrying

 

(Dollars in thousands)

  ​ ​ ​

Value

 

March 31, 2026:

​

​

​

​

Federal Home Loan Bank stock

​

$

18,086

​

Federal Reserve Bank stock

​

​

234,374

​

Investment in unconsolidated subsidiaries

​

​

5,287

​

Other investment securities

​

​

113,177

​

​

​

$

370,924

​

December 31, 2025:

​

​

​

​

Federal Home Loan Bank stock

​

$

18,086

​

Federal Reserve Bank stock

​

​

234,374

​

Investment in unconsolidated subsidiaries

​

​

5,287

​

Other investment securities

​

​

95,681

​

​

​

$

353,428

​
Schedule of amortized cost and fair value of debt and equity securities by contractual maturity

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Securities

​

Securities

 

​

​

Held to Maturity

​

Available for Sale

 

​

​

Amortized

​

Fair

​

Amortized

​

Fair

 

(Dollars in thousands)

  ​ ​ ​

Cost

  ​ ​ ​

Value

  ​ ​ ​

Cost

  ​ ​ ​

Value

 

Due in one year or less

  ​ ​ ​

$

—

​

$

—

  ​ ​ ​

$

19,129

  ​ ​ ​

$

19,092

​

Due after one year through five years

​

​

180,963

​

​

168,977

​

​

403,443

​

​

399,986

​

Due after five years through ten years

​

​

341,754

​

​

297,376

​

​

1,149,497

​

​

1,083,644

​

Due after ten years

​

​

1,484,532

​

​

1,217,785

​

​

5,397,114

​

​

5,027,626

​

​

​

$

2,007,249

​

$

1,684,138

​

$

6,969,183

​

$

6,530,348

​
Schedule of information with respect to sales of available-for-sale securities

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

2025

 

(Dollars in thousands)

​

Sales of Securities Acquired from Independent

​

Investment Securities Sales

​

Total

​

Sale proceeds

​

$

1,279,717

  ​ ​ ​

$

1,594,393

​

$

2,874,110

​

Gross realized gains

​

​

—

​

​

8,892

​

​

8,892

​

Gross realized losses

​

​

—

​

​

(237,703)

​

​

(237,703)

​

Net realized (losses) gain

​

$

—

​

$

(228,811)

​

$

(228,811)

​
Schedule of securities with gross unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

Less Than

​

12 Months

 

​

​

12 Months

​

or More

 

​

​

Gross Unrealized

​

Fair

​

Gross Unrealized

​

Fair

 

(Dollars in thousands)

  ​ ​ ​

Losses

  ​ ​ ​

Value

  ​ ​ ​

Losses

  ​ ​ ​

Value

 

March 31, 2026:

​

​

​

​

​

​

​

​

​

​

​

​

​

Securities Held to Maturity

​

​

​

​

​

​

​

​

​

​

​

​

​

U.S. Government agencies

​

$

—

​

$

—

​

$

16,892

​

$

116,022

​

Residential mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

—

​

​

—

​

​

181,274

​

​

942,578

​

Residential collateralized mortgage-obligations issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

—

​

​

—

​

​

58,553

​

​

313,553

​

Commercial mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

—

​

​

—

​

​

58,228

​

​

274,391

​

Small Business Administration loan-backed securities

​

​

—

​

​

—

​

​

8,164

​

​

37,594

​

​

​

$

—

​

$

—

​

$

323,111

​

$

1,684,138

​

Securities Available for Sale

​

​

​

​

​

​

​

​

​

​

​

​

​

Residential mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

$

4,751

​

$

563,659

​

$

142,770

​

$

774,259

​

Residential collateralized mortgage-obligations issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

3,122

​

​

413,837

​

​

49,755

​

​

267,423

​

Commercial mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

3,447

​

​

391,493

​

​

75,197

​

​

395,381

​

State and municipal obligations

​

​

2,715

​

​

131,282

​

​

148,308

​

​

855,726

​

Small Business Administration loan-backed securities

​

​

302

​

​

159,630

​

​

24,246

​

​

248,694

​

Corporate securities

​

​

2

​

​

9,997

​

​

1,294

​

​

11,706

​

​

​

$

14,339

​

$

1,669,898

​

$

441,570

​

$

2,553,189

​

December 31, 2025:

​

​

​

​

​

​

​

​

​

​

​

​

​

Securities Held to Maturity

​

​

​

​

​

​

​

​

​

​

​

​

​

U.S. Government agencies

​

$

—

​

$

—

​

$

15,767

​

$

117,146

​

Residential mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

—

​

​

—

​

​

177,101

​

​

975,923

​

Residential collateralized mortgage-obligations issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

—

​

​

—

​

​

55,232

​

​

323,874

​

Commercial mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

—

​

​

—

​

​

58,332

​

​

278,579

​

Small Business Administration loan-backed securities

​

​

—

​

​

—

​

​

8,748

​

​

37,328

​

​

​

$

—

​

$

—

​

$

315,180

​

$

1,732,850

​

Securities Available for Sale

​

​

​

​

​

​

​

​

​

​

​

​

​

Residential mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

$

459

​

$

145,357

​

$

137,848

​

$

803,407

​

Residential collateralized mortgage-obligations issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

46

​

​

40,399

​

​

47,059

​

​

278,620

​

Commercial mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

228

​

​

152,299

​

​

73,814

​

​

423,165

​

State and municipal obligations

​

​

572

​

​

43,620

​

​

134,645

​

​

903,784

​

Small Business Administration loan-backed securities

​

​

680

​

​

284,036

​

​

25,408

​

​

202,322

​

Corporate securities

​

​

—

​

​

—

​

​

1,230

​

​

21,769

​

​

​

$

1,985

​

$

665,711

​

$

420,004

​

$

2,633,067

​
Schedule of trading securities

​

​

​

​

​

​

​

​

​

​

  ​ ​ ​

March 31,

​

December 31,

​

(Dollars in thousands)

  ​ ​ ​

2026

 

2025

​

U.S. Government agencies

​

$

14,504

​

$

1,872

​

Residential mortgage pass-through securities issued or guaranteed by U.S.

​

​

​

​

​

​

​

government agencies or sponsored enterprises

​

​

5,787

​

​

9,799

​

Other residential mortgage issued or guaranteed by U.S. government

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

7,302

​

​

1,419

​

Commercial mortgage-backed securities issued by U.S. government

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

27,728

​

​

5,966

​

State and municipal obligations

​

​

26,573

​

​

24,816

​

Small Business Administration loan-backed securities

​

​

34,887

​

​

66,173

​

Other debt securities

​

​

809

​

​

138

​

​

​

$

117,590

​

$

110,183

​
Summary of net gains on trading securities

​

​

​

​

​

​

​

​

​

​

  ​ ​ ​

Three Months Ended

​

​

​

March 31,

​

(Dollars in thousands)

  ​ ​ ​

2026

 

2025

​

Net gains on sales transaction

​

$

383

​

$

362

​

Net unrealized (losses) gains

​

​

(576)

​

​

121

​

Net (losses) gains on trading securities

​

$

(193)

​

$

483

​

​