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v3.25.3

BORROWINGS (Long-Term Borrowings) (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2025 | Dec. 31, 2024
Debt Instrument [Line Items] |  |
Trust Preferred Capital Securities | $ 179,000 | $ 179,000
Subordinated Debt | 608,000 | 250,000
Fair Value Premium (Discount) | (23,860) | (16,239)
Investment in Trust Preferred Capital Securities | 5,542 | 5,542
Total Long-term Borrowings | $ 768,682 | $ 418,303
Basis spread on variable rate | 0.262% | 0.262%
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration] | us-gaap:SecuredOvernightFinancingRateSofrMember | us-gaap:SecuredOvernightFinancingRateSofrMember
Sandy Spring |  |
Debt Instrument [Line Items] |  |
Subordinated Debt | $ 358,000 |
Trust Preferred Capital Notes |  |
Debt Instrument [Line Items] |  |
Remaining fair value discount on acquired notes | 13,200 | $ 14,000
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 | 6.99% | 7.32%
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 | 5.64% | 5.97%
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 | 6.97% | 7.30%
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 | 7.34% | 7.67%
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 | 7.34% | 7.67%
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 | 6.89% | 7.22%
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 | 5.74% | 6.07%
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 | 5.79% | 6.12%
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 | 7.09% | 7.42%
Maturity date | Jan. 23, 2034 | Jan. 23, 2034
AMNB Trust I | American National |  |
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 | 1.35% | 1.35%
Rate | 5.59% | 5.92%
Maturity date | Jun. 30, 2036 | Jun. 30, 2036
MidCarolina Trust I | American National |  |
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 | 3.45% | 3.45%
Rate | 7.43% | 7.76%
Maturity date | Nov. 07, 2032 | Nov. 07, 2032
MidCarolina Trust II | American National |  |
Debt Instrument [Line Items] |  |
Trust Preferred Capital Securities | $ 3,500 | $ 3,500
Investment in Trust Preferred Capital Securities | $ 109 | $ 109
Basis spread on variable rate | 2.95% | 2.95%
Rate | 6.93% | 7.26%
Maturity date | Jan. 07, 2034 | Jan. 07, 2034
Subordinated Debt [Member] |  |
Debt Instrument [Line Items] |  |
Remaining fair value discount on acquired notes | $ 10,700 | $ 2,200
Subordinated Debt [Member] | Scenario, Plan [Member] |  |
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 | 2.88% | 2.875%
Maturity date | Dec. 15, 2031 | Dec. 15, 2031
2032 Subordinate Debt | Sandy Spring |  |
Debt Instrument [Line Items] |  |
Subordinated Debt | $ 190,000 |
Basis spread on variable rate | 0.00% |
Rate | 3.88% |
Maturity date | Mar. 30, 2032 |
2032 Subordinate Debt | Scenario, Plan [Member] | Sandy Spring |  |
Debt Instrument [Line Items] |  |
Basis spread on variable rate | 1.965% |
2029 Subordinate Debt | Sandy Spring |  |
Debt Instrument [Line Items] |  |
Subordinated Debt | $ 168,000 |
Basis spread on variable rate | 2.62% |
Rate | 6.86% |
Maturity date | Nov. 15, 2029 |
2029 Subordinate Debt | Scenario, Plan [Member] | Sandy Spring |  |
Debt Instrument [Line Items] |  |
Basis spread on variable rate | 2.62% |
Spread adjustment | 0.26% |

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