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BORROWINGS (Long-Term Borrowings) (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 | Dec. 31, 2023
Debt Instrument [Line Items] |  |
Trust Preferred Capital Securities | $ 150,500 | $ 150,500
Subordinated Debt | 250,000 | 250,000
Fair Value Premium (Discount) | (13,840) | (14,134)
Investment in Trust Preferred Capital Securities | 4,659 | 4,659
Total Long-term Borrowings | $ 391,319 | $ 391,025
SOFR |  |
Debt Instrument [Line Items] |  |
Basis spread on variable rate | 0.262% | 0.262%
Trust Preferred Capital Notes |  |
Debt Instrument [Line Items] |  |
Remaining fair value discount on acquired notes | $ 11,400 | $ 11,700
Statutory Trust I |  |
Debt Instrument [Line Items] |  |
Trust Preferred Capital Securities | 22,500 | 22,500
Investment in Trust Preferred Capital Securities | $ 696 | $ 696
Basis spread on variable rate | 2.75% | 2.75%
Rate | 8.31% | 8.34%
Maturity date | Jun. 17, 2034 | Jun. 17, 2034
Statutory Trust II |  |
Debt Instrument [Line Items] |  |
Trust Preferred Capital Securities | $ 36,000 | $ 36,000
Investment in Trust Preferred Capital Securities | $ 1,114 | $ 1,114
Basis spread on variable rate | 1.40% | 1.40%
Rate | 6.96% | 6.99%
Maturity date | Jun. 15, 2036 | Jun. 15, 2036
VFG Limited Liability Trust I Indenture |  |
Debt Instrument [Line Items] |  |
Trust Preferred Capital Securities | $ 20,000 | $ 20,000
Investment in Trust Preferred Capital Securities | $ 619 | $ 619
Basis spread on variable rate | 2.73% | 2.73%
Rate | 8.29% | 8.32%
Maturity date | Mar. 18, 2034 | Mar. 18, 2034
FNB Statutory Trust II Indenture |  |
Debt Instrument [Line Items] |  |
Trust Preferred Capital Securities | $ 12,000 | $ 12,000
Investment in Trust Preferred Capital Securities | $ 372 | $ 372
Basis spread on variable rate | 3.10% | 3.10%
Rate | 8.66% | 8.69%
Maturity date | Jun. 26, 2033 | Jun. 26, 2033
Gateway Capital Statutory Trust I |  |
Debt Instrument [Line Items] |  |
Trust Preferred Capital Securities | $ 8,000 | $ 8,000
Investment in Trust Preferred Capital Securities | $ 248 | $ 248
Basis spread on variable rate | 3.10% | 3.10%
Rate | 8.66% | 8.69%
Maturity date | Sep. 17, 2033 | Sep. 17, 2033
Gateway Capital Statutory Trust II |  |
Debt Instrument [Line Items] |  |
Trust Preferred Capital Securities | $ 7,000 | $ 7,000
Investment in Trust Preferred Capital Securities | $ 217 | $ 217
Basis spread on variable rate | 2.65% | 2.65%
Rate | 8.21% | 8.24%
Maturity date | Jun. 17, 2034 | Jun. 17, 2034
Gateway Capital Statutory Trust III |  |
Debt Instrument [Line Items] |  |
Trust Preferred Capital Securities | $ 15,000 | $ 15,000
Investment in Trust Preferred Capital Securities | $ 464 | $ 464
Basis spread on variable rate | 1.50% | 1.50%
Rate | 7.06% | 7.09%
Maturity date | May 30, 2036 | May 30, 2036
Gateway Capital Statutory Trust IV |  |
Debt Instrument [Line Items] |  |
Trust Preferred Capital Securities | $ 25,000 | $ 25,000
Investment in Trust Preferred Capital Securities | $ 774 | $ 774
Basis spread on variable rate | 1.55% | 1.55%
Rate | 7.11% | 7.14%
Maturity date | Jul. 30, 2037 | Jul. 30, 2037
MFC Capital Trust II |  |
Debt Instrument [Line Items] |  |
Trust Preferred Capital Securities | $ 5,000 | $ 5,000
Investment in Trust Preferred Capital Securities | $ 155 | $ 155
Basis spread on variable rate | 2.85% | 2.85%
Rate | 8.41% | 8.44%
Maturity date | Jan. 23, 2034 | Jan. 23, 2034
Subordinated Debt |  |
Debt Instrument [Line Items] |  |
Remaining fair value discount on acquired notes | $ 2,400 | $ 2,500
Subordinated Debt | SOFR | Scenario, Plan |  |
Debt Instrument [Line Items] |  |
Basis spread on variable rate | 1.86% | 1.86%
2031 Subordinate Debt |  |
Debt Instrument [Line Items] |  |
Subordinated Debt | $ 250,000 | $ 250,000
Basis spread on variable rate | 0.00% | 0.00%
Rate | 2.875% | 2.875%
Maturity date | Dec. 15, 2031 | Dec. 15, 2031

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