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Fair Value Measurement - Balance Sheet Grouping (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Carrying Amount |  |
Financial assets: |  |
Cash and cash equivalents | $ 486,297 | $ 560,510
Investment securities: |  |
HTM, at carrying value | 1,172,332 | 1,186,152
Mortgage-backed securities: |  |
HTM, at carrying value | 116,071 | 120,901
FHLB stock, at cost | 40,291 | 11,936
Equity investments | 4,301 | 4,383
Loans, net of allowance for loan losses | 4,533,772 | 4,481,836
Loans held for sale | 768 | 10,894
Financial liabilities: |  |
Deposits | 6,435,702 | 6,549,681
Other borrowings | 105,810 | 509,820
FHLB borrowings | 760,046 | 212,648
Subordinated notes, net of unamortized debt issuance costs | 92,006 | 93,877
Trust preferred subordinated debentures, net of unamortized debt issuance costs | 60,273 | 60,270
Estimated Fair Value |  |
Financial assets: |  |
Cash and cash equivalents | 486,297 | 560,510
Investment securities: |  |
HTM, at carrying value | 1,060,369 | 1,054,739
Mortgage-backed securities: |  |
HTM, at carrying value | 109,154 | 111,423
FHLB stock, at cost | 40,291 | 11,936
Equity investments | 4,301 | 4,383
Loans, net of allowance for loan losses | 4,418,820 | 4,198,879
Loans held for sale | 768 | 10,894
Financial liabilities: |  |
Deposits | 6,436,589 | 6,534,929
Other borrowings | 105,668 | 510,242
FHLB borrowings | 755,052 | 202,750
Subordinated notes, net of unamortized debt issuance costs | 85,253 | 86,285
Trust preferred subordinated debentures, net of unamortized debt issuance costs | 51,946 | 57,480
Estimated Fair Value | Level 1 |  |
Financial assets: |  |
Cash and cash equivalents | 486,297 | 560,510
Investment securities: |  |
HTM, at carrying value | 0 | 0
Mortgage-backed securities: |  |
HTM, at carrying value | 0 | 0
FHLB stock, at cost | 0 | 0
Equity investments | 0 | 0
Loans, net of allowance for loan losses | 0 | 0
Loans held for sale | 0 | 0
Financial liabilities: |  |
Deposits | 0 | 0
Other borrowings | 0 | 0
FHLB borrowings | 0 | 0
Subordinated notes, net of unamortized debt issuance costs | 0 | 0
Trust preferred subordinated debentures, net of unamortized debt issuance costs | 0 | 0
Estimated Fair Value | Level 2 |  |
Financial assets: |  |
Cash and cash equivalents | 0 | 0
Investment securities: |  |
HTM, at carrying value | 1,060,369 | 1,054,739
Mortgage-backed securities: |  |
HTM, at carrying value | 109,154 | 111,423
FHLB stock, at cost | 40,291 | 11,936
Equity investments | 4,301 | 4,383
Loans, net of allowance for loan losses | 0 | 0
Loans held for sale | 768 | 10,894
Financial liabilities: |  |
Deposits | 6,436,589 | 6,534,929
Other borrowings | 105,668 | 510,242
FHLB borrowings | 755,052 | 202,750
Subordinated notes, net of unamortized debt issuance costs | 85,253 | 86,285
Trust preferred subordinated debentures, net of unamortized debt issuance costs | 51,946 | 57,480
Estimated Fair Value | Level 3 |  |
Financial assets: |  |
Cash and cash equivalents | 0 | 0
Investment securities: |  |
HTM, at carrying value | 0 | 0
Mortgage-backed securities: |  |
HTM, at carrying value | 0 | 0
FHLB stock, at cost | 0 | 0
Equity investments | 0 | 0
Loans, net of allowance for loan losses | 4,418,820 | 4,198,879
Loans held for sale | 0 | 0
Financial liabilities: |  |
Deposits | 0 | 0
Other borrowings | 0 | 0
FHLB borrowings | 0 | 0
Subordinated notes, net of unamortized debt issuance costs | 0 | 0
Trust preferred subordinated debentures, net of unamortized debt issuance costs | $ 0 | $ 0

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- Definition Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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