| Schedule of recorded amount of assets and liabilities measured at fair value on a recurring basis |
| | | | | | | | | | | | | | | | | | Quoted Prices | | | | | | | | | | | | In Active | | Significant | | | | | | | | | Markets | | Other | | Significant | | | | | | for Identical | | Observable | | Unobservable | | | | | | Assets | | Inputs | | Inputs | (Dollars in thousands) | | Fair Value | | (Level 1) | | (Level 2) | | (Level 3) | June 30, 2026: | | | | | | | | | | | | | Assets | | | | | | | | | | | | | Derivative financial instruments | | $ | 148,889 | | $ | — | | $ | 148,889 | | $ | — | Mortgage loans held for sale | | | 68,738 | | | — | | | 68,738 | | | — | Trading securities | | | 191,094 | | | — | | | 191,094 | | | — | Securities available for sale: | | | | | | | | | | | | | Residential mortgage-backed securities issued by U.S. government | | | | | | | | | | | | | agencies or sponsored enterprises | | | 1,886,566 | | | — | | | 1,886,566 | | | — | Residential collateralized mortgage-obligations issued by U.S. government | | | | | | | | | | | | | agencies or sponsored enterprises | | | 2,034,159 | | | — | | | 2,034,159 | | | — | Commercial mortgage-backed securities issued by U.S. government | | | | | | | | | | | | | agencies or sponsored enterprises | | | 1,017,479 | | | — | | | 1,017,479 | | | — | State and municipal obligations | | | 1,114,750 | | | — | | | 1,114,750 | | | — | Small Business Administration loan-backed securities | | | 523,117 | | | — | | | 523,117 | | | — | Corporate securities | | | 22,106 | | | — | | | 22,106 | | | — | Total securities available for sale | | | 6,598,177 | | | — | | | 6,598,177 | | | — | Mortgage servicing rights | | | 91,442 | | | — | | | — | | | 91,442 | SBA servicing asset | | | 4,954 | | | — | | | — | | | 4,954 | | | $ | 7,103,294 | | $ | — | | $ | 7,006,898 | | $ | 96,396 | Liabilities | | | | | | | | | | | | | Derivative financial instruments | | $ | 606,665 | | $ | — | | $ | 606,665 | | $ | — | | | | | | | | | | | | | | December 31, 2025: | | | | | | | | | | | | | Assets | | | | | | | | | | | | | Derivative financial instruments | | $ | 222,886 | | $ | — | | $ | 222,886 | | $ | — | Mortgage loans held for sale | | | 61,400 | | | — | | | 61,400 | | | — | Trading securities | | | 110,183 | | | — | | | 110,183 | | | — | Securities available for sale: | | | | | | | | | | | | | Residential mortgage-backed securities issued by U.S. government | | | | | | | | | | | | | agencies or sponsored enterprises | | | 1,698,108 | | | — | | | 1,698,108 | | | — | Residential collateralized mortgage-obligations issued by U.S. government | | | | | | | | | | | | | agencies or sponsored enterprises | | | 2,185,584 | | | — | | | 2,185,584 | | | — | Commercial mortgage-backed securities issued by U.S. government | | | | | | | | | | | | | agencies or sponsored enterprises | | | 832,449 | | | — | | | 832,449 | | | — | State and municipal obligations | | | 1,007,412 | | | — | | | 1,007,412 | | | — | Small Business Administration loan-backed securities | | | 568,433 | | | — | | | 568,433 | | | — | Corporate securities | | | 21,770 | | | — | | | 21,770 | | | — | Total securities available for sale | | | 6,313,756 | | | — | | | 6,313,756 | | | — | Mortgage servicing rights | | | 84,032 | | | — | | | — | | | 84,032 | SBA servicing asset | | | 5,512 | | | — | | | — | | | 5,512 | | | $ | 6,797,769 | | $ | — | | $ | 6,708,225 | | $ | 89,544 | Liabilities | | | | | | | | | | | | | Derivative financial instruments | | $ | 554,748 | | $ | — | | $ | 554,748 | | $ | — |
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| Schedule of estimated fair value, and related carrying amount, of the Company's financial instruments |
| | | | | | | | | | | | | | | | | | | Carrying | | Fair | | | | | | | | | | | (Dollars in thousands) | | Amount | | Value | | Level 1 | | Level 2 | | Level 3 | | June 30, 2026 | | | | | | | | | | | | | | | | | Financial assets: | | | | | | | | | | | | | | | | | Cash and cash equivalents | | $ | 2,350,312 | | $ | 2,350,312 | | $ | 2,350,312 | | $ | — | | $ | — | | Trading securities | | | 191,094 | | | 191,094 | | | — | | | 191,094 | | | — | | Investment securities | | | 8,920,917 | | | 8,606,205 | | | 287,033 | | | 8,239,219 | | | 79,953 | | Loans held for sale | | | 405,441 | | | 406,234 | | | — | | | 406,234 | | | — | | Loans, net of allowance for credit losses | | | 50,260,208 | | | 49,968,238 | | | — | | | — | | | 49,968,238 | | Accrued interest receivable | | | 238,893 | | | 238,893 | | | — | | | 36,943 | | | 201,950 | | Mortgage servicing rights | | | 91,442 | | | 91,442 | | | — | | | — | | | 91,442 | | SBA servicing asset | | | 4,954 | | | 4,954 | | | — | | | — | | | 4,954 | | Interest rate swap – non-designated hedge | | | 147,342 | | | 147,342 | | | — | | | 147,342 | | | — | | Other derivative financial instruments (mortgage banking related) | | | 1,547 | | | 1,547 | | | — | | | 1,547 | | | — | | Financial liabilities: | | | | | | | | | | | | | | | | | Deposits | | | | | | | | | | | | | | | | | Noninterest-bearing | | | 13,451,094 | | | 13,451,094 | | | — | | | 13,451,094 | | | — | | Interest-bearing other than time deposits | | | 35,038,294 | | | 35,038,294 | | | — | | | 35,038,294 | | | — | | Time deposits | | | 7,860,422 | | | 7,840,476 | | | — | | | 7,840,476 | | | — | | Federal funds purchased and securities sold under agreements to repurchase | | | 569,486 | | | 569,486 | | | — | | | 569,486 | | | — | | Corporate and subordinated debentures | | | 696,749 | | | 669,627 | | | — | | | 669,627 | | | — | | Other borrowings | | | 300,000 | | | 299,995 | | | — | | | 299,995 | | | — | | Accrued interest payable | | | 34,948 | | | 34,948 | | | — | | | 34,948 | | | — | | Interest rate swap – non-designated hedge | | | 606,404 | | | 606,404 | | | — | | | 606,404 | | | — | | Other derivative financial instruments (mortgage banking related) | | | 261 | | | 261 | | | — | | | 261 | | | — | | December 31, 2025 | | | | | | | | | | | | | | | | | Financial assets: | | | | | | | | | | | | | | | | | Cash and cash equivalents | | $ | 3,172,483 | | $ | 3,172,483 | | $ | 3,172,483 | | $ | — | | $ | — | | Trading securities | | | 110,183 | | | 110,183 | | | — | | | 110,183 | | | — | | Investment securities | | | 8,715,214 | | | 8,400,034 | | | 274,730 | | | 8,046,606 | | | 78,698 | | Loans held for sale | | | 345,343 | | | 348,381 | | | — | | | 348,381 | | | — | | Loans, net of allowance for credit losses | | | 48,013,330 | | | 47,378,022 | | | — | | | — | | | 47,378,022 | | Accrued interest receivable | | | 233,265 | | | 233,265 | | | — | | | 35,302 | | | 197,963 | | Mortgage servicing rights | | | 84,032 | | | 84,032 | | | — | | | — | | | 84,032 | | SBA servicing asset | | | 5,512 | | | 5,512 | | | — | | | — | | | 5,512 | | Interest rate swap – non-designated hedge | | | 221,835 | | | 221,835 | | | — | | | 221,835 | | | — | | Other derivative financial instruments (mortgage banking related) | | | 1,051 | | | 1,051 | | | — | | | 1,051 | | | — | | Financial liabilities: | | | | | | | | | | | | | | | | | Deposits | | | | | | | | | | | | | | | | | Noninterest-bearing | | | 13,375,697 | | | 13,375,697 | | | — | | | 13,375,697 | | | — | | Interest-bearing other than time deposits | | | 34,410,867 | | | 34,410,867 | | | — | | | 34,410,867 | | | — | | Time deposits | | | 7,359,233 | | | 7,347,648 | | | — | | | 7,347,648 | | | — | | Federal funds purchased and securities sold under agreements to repurchase | | | 618,215 | | | 618,215 | | | — | | | 618,215 | | | — | | Corporate and subordinated debentures | | | 696,536 | | | 683,772 | | | — | | | 683,772 | | | — | | Accrued interest payable | | | 48,972 | | | 48,972 | | | — | | | 48,972 | | | — | | Interest rate swap – non-designated hedge | | | 554,433 | | | 554,433 | | | — | | | 554,433 | | | — | | Other derivative financial instruments (mortgage banking related) | | | 315 | | | 315 | | | — | | | 315 | | | — | |
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