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Fair Value Measurements and Fair Value of Financial Instruments, Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Financial assets [Abstract] |  |
HTM securities | $ 783,986 | $ 812,647
Carrying Amount [Member] | Level 1 [Member] |  |
Financial liabilities [Abstract] |  |
Subordinated debt | 120,061 | 98,000
Carrying Amount [Member] | Level 2 [Member] |  |
Financial assets [Abstract] |  |
HTM securities | 914,520 | 919,517
Financial liabilities [Abstract] |  |
Time deposits | 1,344,199 | 433,772
Long-term debt | 29,834 | 4,815
Junior subordinated debt | 101,196 | 101,196
Carrying Amount [Member] | Level 3 [Member] |  |
Financial assets [Abstract] |  |
Net loans | 9,556,887 | 8,049,909
Estimated Fair Value [Member] | Level 1 [Member] |  |
Financial liabilities [Abstract] |  |
Subordinated debt | 110,057 | 92,883
Estimated Fair Value [Member] | Level 2 [Member] |  |
Financial assets [Abstract] |  |
HTM securities | 783,986 | 812,647
Financial liabilities [Abstract] |  |
Time deposits | 1,301,989 | 413,868
Long-term debt | 29,114 | 4,539
Junior subordinated debt | 99,259 | 98,372
Estimated Fair Value [Member] | Level 3 [Member] |  |
Financial assets [Abstract] |  |
Net loans | $ 9,097,545 | $ 7,840,350

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