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BORROWINGS (Narrative) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Subordinated Borrowing [Line Items] |  |  |
Remaining available balance for the federal funds lines | $ 682,000,000.0 | $ 1,000,000,000.0 |
Maximum collateral dependent line of credit with the FHLB | 6,200,000,000 | 6,000,000,000.0 |
Trust Preferred Capital Securities | 150,500,000 | 150,500,000 |
Fair value discount | 14,134,000 | 15,296,000 |
Net proceeds from issuance of long-term borrowings | 0 | 0 | $ 246,869,000
Subordinated Debt | 250,000,000 | 250,000,000 |
Long-term debt, early repayments | 0 | 0 | $ 364,695,000
Remaining borrowing capacity | 25,000,000.0 | 25,000,000.0 |
Federal Reserve Bank Term Funding Program |  |  |
Subordinated Borrowing [Line Items] |  |  |
Additional funding available | 522,900,000 |  |
FHLB Secured Line Of Credit |  |  |
Subordinated Borrowing [Line Items] |  |  |
Maximum collateral dependent line of credit with the FHLB | 1,700,000,000 | 1,800,000,000 |
Remaining credit availability on collateral dependent line of credit with the FHLB | 989,000 | 814,000 |
Acquired Trust Preferred Capital Notes |  |  |
Subordinated Borrowing [Line Items] |  |  |
Fair value discount | 11,700,000 | 12,500,000 |
2031 Subordinate Debt |  |  |
Subordinated Borrowing [Line Items] |  |  |
Fair value discount | 2,500,000 | 2,800,000 |
Subordinated Debt | $ 250,000,000 | $ 250,000,000 |
Stated percentage on debt instrument | 2.875% | 2.875% |
Three-month CME SOFR rate plus | 0.00% | 0.00% |
Maturity date | Dec. 15, 2031 | Dec. 15, 2031 |
Previous bank acquisitions | Trust Preferred Capital Notes |  |  |
Subordinated Borrowing [Line Items] |  |  |
Trust Preferred Capital Securities | $ 58,500,000 |  |
Previous bank acquisitions | Acquired Trust Preferred Capital Notes |  |  |
Subordinated Borrowing [Line Items] |  |  |
Trust Preferred Capital Securities | $ 92,000,000.0 |  |

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- Definition Federal funds lines available balance. + References No definition available. + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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- Definition Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(2)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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- Definition Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 + Details
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