XML 43 R32.htm IDEA: XBRL DOCUMENT v3.24.1.u1
Securities (Tables)
 3 Months Ended
Mar. 31, 2024
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, 2024:

​

​

​

​

​

​

​

​

​

​

​

​

​

U.S. Government agencies

​

$

197,269

​

$

—

​

$

(25,821)

​

$

171,448

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

1,406,440

​

​

—

​

​

(246,764)

​

​

1,159,676

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

437,718

​

​

—

​

​

(72,593)

​

​

365,125

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

352,399

​

​

—

​

​

(73,294)

​

​

279,105

​

Small Business Administration loan-backed securities

​

​

52,763

​

​

—

​

​

(11,550)

​

​

41,213

​

​

​

$

2,446,589

​

$

—

​

$

(430,022)

​

$

2,016,567

​

December 31, 2023:

​

​

​

​

​

​

​

​

​

​

​

​

​

U.S. Government agencies

​

$

197,267

​

$

—

​

$

(24,607)

​

$

172,660

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

1,438,102

​

​

—

​

​

(227,312)

​

​

1,210,790

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

444,883

​

​

—

​

​

(68,139)

​

​

376,744

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

354,055

​

​

—

​

​

(71,327)

​

​

282,728

​

Small Business Administration loan-backed securities

​

​

53,133

​

​

—

​

​

(11,319)

​

​

41,814

​

​

​

$

2,487,440

​

$

—

​

$

(402,704)

​

$

2,084,736

​
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, 2024:

​

​

​

​

​

​

​

​

​

​

​

​

​

U.S. Treasuries

​

$

24,920

​

$

—

​

$

(333)

​

$

24,587

​

U.S. Government agencies

​

​

246,118

​

​

—

​

​

(22,313)

​

​

223,805

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

 

1,780,838

​

 

161

​

 

(288,576)

​

 

1,492,423

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

611,044

​

​

4

​

​

(102,936)

​

​

508,112

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

1,213,549

​

​

767

​

​

(202,099)

​

​

1,012,217

​

State and municipal obligations

​

 

1,127,834

​

 

2

​

 

(167,477)

​

 

960,359

​

Small Business Administration loan-backed securities

​

 

393,770

​

 

52

​

 

(43,779)

​

 

350,043

​

Corporate securities

​

​

30,521

​

​

—

​

​

(3,667)

​

​

26,854

​

​

​

$

5,428,594

​

$

986

​

$

(831,180)

​

$

4,598,400

​

December 31, 2023:

​

​

​

​

​

​

​

​

​

​

​

​

​

U.S. Treasuries

​

$

74,720

​

$

—

​

$

(830)

​

$

73,890

​

U.S. Government agencies

​

​

246,089

​

​

—

​

​

(21,383)

​

​

224,706

​

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

​

 

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

1,822,104

​

 

294

​

 

(264,092)

​

 

1,558,306

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

626,735

​

​

—

​

​

(99,313)

​

​

527,422

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

1,217,125

​

​

1,516

​

​

(194,471)

​

​

1,024,170

​

State and municipal obligations

​

​

1,129,750

​

 

2

​

 

(152,291)

​

 

977,461

​

Small Business Administration loan-backed securities

​

 

413,950

​

 

86

​

 

(42,350)

​

 

371,686

​

Corporate securities

​

 

30,533

​

​

—

​

​

(3,786)

​

​

26,747

​

​

​

$

5,561,006

​

$

1,898

​

$

(778,516)

​

$

4,784,388

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

​

​

​

​

​

​

​

​

Carrying

 

(Dollars in thousands)

    

Value

 

March 31, 2024:

​

​

​

​

Federal Home Loan Bank stock

​

$

18,086

​

Federal Reserve Bank stock

​

​

150,261

​

Investment in unconsolidated subsidiaries

​

 

3,563

​

Other nonmarketable investment securities

​

 

15,375

​

​

​

$

187,285

​

December 31, 2023:

​

​

​

​

Federal Home Loan Bank stock

​

$

22,836

​

Federal Reserve Bank stock

​

​

150,261

​

Investment in unconsolidated subsidiaries

​

 

3,563

​

Other nonmarketable investment securities

​

 

15,383

​

​

​

$

192,043

​
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

    

$

64,365

​

$

63,576

    

$

157,891

    

$

155,556

​

Due after one year through five years

​

 

36,550

​

 

32,413

​

 

262,765

​

 

246,685

​

Due after five years through ten years

​

 

468,529

​

 

399,174

​

 

1,295,555

​

 

1,111,329

​

Due after ten years

​

 

1,877,145

​

 

1,521,404

​

 

3,712,383

​

 

3,084,830

​

​

​

$

2,446,589

​

$

2,016,567

​

$

5,428,594

​

$

4,598,400

​
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

​

Twelve Months

 

​

​

Twelve Months

​

or More

 

​

​

Gross Unrealized

​

Fair

​

Gross Unrealized

​

Fair

 

(Dollars in thousands)

    

Losses

    

Value

    

Losses

    

Value

 

March 31, 2024:

​

​

​

​

​

​

​

​

​

​

​

​

​

Securities Held to Maturity

​

​

​

​

​

​

​

​

​

​

​

​

​

U.S. Government agencies

​

$

—

​

$

—

​

$

25,821

​

$

171,448

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

—

​

​

—

​

​

246,764

​

​

1,159,676

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

—

​

 

—

​

 

72,593

​

 

365,125

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

—

​

​

—

​

​

73,294

​

​

279,105

​

Small Business Administration loan-backed securities

​

​

—

​

​

—

​

​

11,550

​

​

41,213

​

​

​

$

—

​

$

—

​

$

430,022

​

$

2,016,567

​

Securities Available for Sale

​

​

​

​

​

​

​

​

​

​

​

​

​

U.S. Treasuries

​

$

—

​

$

—

​

$

333

​

$

24,597

​

U.S. Government agencies

​

​

—

​

​

—

​

​

22,313

​

​

223,805

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

135

​

​

8,878

​

​

288,441

​

​

1,473,944

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

—

​

 

—

​

 

102,936

​

 

506,900

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

 

63

​

​

14,929

​

​

202,036

​

​

932,902

​

State and municipal obligations

​

 

1,981

​

​

19,989

​

​

165,496

​

​

936,573

​

Small Business Administration loan-backed securities

​

 

62

​

​

16,734

​

​

43,717

​

​

317,469

​

Corporate securities

​

​

10

​

​

489

​

​

3,657

​

​

26,366

​

​

​

$

2,251

​

$

61,019

​

$

828,929

​

$

4,442,556

​

December 31, 2023:

​

​

​

​

​

​

​

​

​

​

​

​

​

Securities Held to Maturity

​

​

​

​

​

​

​

​

​

​

​

​

​

U.S. Government agencies

​

$

—

​

$

—

​

$

24,607

​

$

172,660

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

—

​

​

—

​

​

227,312

​

​

1,210,790

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

—

​

 

—

​

 

68,139

​

 

376,745

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

—

​

​

—

​

​

71,327

​

​

282,728

​

Small Business Administration loan-backed securities

​

​

—

​

​

—

​

​

11,319

​

​

41,814

​

​

​

$

—

​

$

—

​

$

402,704

​

$

2,084,737

​

Securities Available for Sale

​

​

​

​

​

​

​

​

​

​

​

​

​

U.S. Treasuries

​

$

—

​

$

—

​

$

830

​

$

73,890

​

U.S. Government agencies

​

​

—

​

​

—

​

​

21,383

​

​

224,706

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

122

​

​

9,358

​

​

263,970

​

​

1,539,208

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

—

​

 

—

​

 

99,313

​

 

527,422

​

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

​

​

​

​

​

​

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

91

​

​

7,959

​

​

194,380

​

​

955,059

​

State and municipal obligations

​

​

177

​

​

6,340

​

​

152,114

​

​

967,305

​

Small Business Administration loan-backed securities

​

​

128

​

​

42,447

​

​

42,222

​

​

304,770

​

Corporate securities

​

 

18

​

​

480

​

​

3,768

​

​

26,267

​

​

​

$

536

​

$

66,584

​

$

777,980

​

$

4,618,627

​
Schedule of trading securities

​

​

​

​

​

​

​

​

​

​

    

March 31,

​

December 31,

​

(Dollars in thousands)

    

2024

 

2023

​

U.S. Government agencies

​

$

10,352

​

$

1,537

​

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

​

​

​

​

​

​

​

government agencies or sponsored enterprises

​

​

11,383

​

​

14,461

​

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

​

 

​

​

 

​

​

agencies or sponsored enterprises

​

 

1,148

​

 

—

​

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

​

​

​

​

​

​

​

agencies or sponsored enterprises

​

​

8,467

​

​

—

​

State and municipal obligations

​

​

31,263

​

​

14,620

​

Other debt securities

​

​

3,575

​

​

703

​

​

​

$

66,188

​

$

31,321

​
Summary of net gains (losses) on trading securities

​

​

​

​

​

​

​

​

​

​

    

Three Months Ended

​

​

​

March 31,

​

(Dollars in thousands)

    

2024

 

2023

​

Net gains (losses) on sales transaction

​

$

54

​

$

(139)

​

Net mark to mark gains (losses)

​

​

12

​

​

(6)

​

Net gains (losses) on trading securities

​

$

66

​

$

(145)

​

​