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ACQUISITIONS (Details) $ in Thousands |  |  |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | ---
Feb. 01, 2024 USD ($) | Mar. 01, 2023 USD ($) | May 13, 2022 USD ($) item | Aug. 02, 2021 USD ($) | Jul. 01, 2021 USD ($) | Jun. 01, 2021 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Acquisitions |  |  |  |  |  |  |  |  |
Goodwill |  |  |  |  |  |  | $ 845,396 | $ 841,841 | $ 799,109
Other intangibles |  |  |  |  |  |  |  | 2,900 |
Cash |  |  |  |  |  |  | 8,517 | 668 | 29,329
Certain assets of six financial services companies |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Aggregate consideration in contingent consideration arrangements |  |  |  |  |  |  | 1,400 |  |
Purchase price of acquisition |  |  |  |  |  |  | 8,100 |  |
Assets acquired |  |  |  |  |  |  | 5,100 |  |
Goodwill |  |  |  |  |  |  | 3,000 |  |
Purchase price in cash |  |  |  |  |  |  | $ 6,700 |  |
Certain assets of six financial services companies | Maximum |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Term of revenue target for contingent consideration arrangements |  |  |  |  |  |  | 5 years |  |
Certain assets of six financial services companies | Minimum |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Term of revenue target for contingent consideration arrangements |  |  |  |  |  |  | 2 years |  |
Certain assets of six financial services companies | Customer list intangible |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Other intangibles |  |  |  |  |  |  | $ 4,900 |  |
Axiom |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  | 800 |  |
Direct expenses |  |  |  |  |  |  | 1,800 |  |
Purchase price of acquisition |  |  |  |  |  |  | 1,819 |  |
Loans |  |  |  |  |  |  | 0 |  |
Investment securities |  |  |  |  |  |  | 0 |  |
Deposits |  |  |  |  |  |  | 0 |  |
Goodwill |  | $ 600 |  |  |  |  | 625 |  |
Other intangibles |  | 1,200 |  |  |  |  |  |  |
Contingent consideration |  |  |  |  |  |  | 0 |  |
Purchase price in cash |  | $ 1,800 |  |  |  |  |  |  |
Axiom | Core deposit intangibles |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Deposits |  |  |  |  |  |  | 0 |  |
NuVantage Insurance Corp. |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  | 1,300 | 1,300 | 700
Direct expenses |  |  |  |  |  |  | 2,000 | 1,300 | 600
Cash |  |  |  |  |  | $ 2,900 |  |  |
Fringe Benefits Design of Minnesota, Inc |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  | 3,500 | 2,800 |
Direct expenses |  |  |  |  |  |  | 4,100 | 2,500 |
Goodwill |  |  |  |  | $ 2,100 |  |  |  |
Period considered for additional consideration based on future retained revenue |  |  |  |  | 2 years |  |  |  |
Consideration payable term |  |  |  |  | 30 months |  |  |  |
Contingent consideration |  |  |  |  | $ 1,400 |  |  |  |
Cash |  |  |  |  | $ 15,400 |  |  |  |
Contingent consideration, measurement input |  |  |  |  | 0.0105 |  |  |  |
Fair value contingent consideration adjustment |  |  |  |  |  |  | 2,700 |  |
Fringe Benefits Design of Minnesota, Inc | Adjusted level of retained revenue |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Contingent consideration, measurement input |  |  |  |  | 0.50 |  |  |  |
Fringe Benefits Design of Minnesota, Inc | Maximum |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Contingent consideration |  |  |  |  | $ 2,700 |  |  |  |
Fringe Benefits Design of Minnesota, Inc | Minimum |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Contingent consideration |  |  |  |  | 0 |  |  |  |
Steuben Trust Corporation |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Increase (decrease) in other liabilities as a result of reclassification and adjustment |  |  |  |  |  |  | (100) |  |
Thomas Gregory Associates Insurance Brokers, Inc. |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  | 4,400 | 3,100 | 600
Direct expenses |  |  |  |  |  |  | 1,900 | 1,800 | $ 600
Period considered for additional consideration based on future retained revenue |  |  |  | 3 years |  |  |  |  |
Contingent consideration |  |  |  | $ 1,500 |  |  |  |  |
Contingent consideration, measurement input |  |  |  | 0.450 |  |  |  |  |
Fair value contingent consideration adjustment |  |  |  |  |  |  | 1,000 |  |
Thomas Gregory Associates Insurance Brokers, Inc. | Within two years from acquisition |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Consideration payable term |  |  |  | 2 years |  |  |  |  |
Thomas Gregory Associates Insurance Brokers, Inc. | Within three years from acquisition |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Consideration payable term |  |  |  | 3 years |  |  |  |  |
Thomas Gregory Associates Insurance Brokers, Inc. | Maximum |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Cash |  |  |  | $ 3,400 |  |  |  |  |
Contingent consideration, measurement input |  |  |  | 0.0109 |  |  |  |  |
Thomas Gregory Associates Insurance Brokers, Inc. | Minimum |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Cash |  |  |  | $ 0 |  |  |  |  |
Contingent consideration, measurement input |  |  |  | 0.0082 |  |  |  |  |
Elmira Savings Bank |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  | 14,900 | 12,100 |
Direct expenses |  |  |  |  |  |  | $ 4,900 | 3,100 |
Purchase price of acquisition |  |  | $ 82,200 |  |  |  |  | 82,179 |
Number of county | item |  |  | 5 |  |  |  |  |  |
Assets acquired |  |  | $ 583,600 |  |  |  |  |  |
Loans |  |  | 436,800 |  |  |  |  | 436,796 |
Investment securities |  |  | 11,300 |  |  |  |  | 11,305 |
Deposits |  |  | 522,300 |  |  |  |  | 522,295 |
Goodwill |  |  | 42,100 |  |  |  |  | 42,105 |
Contingent consideration |  |  |  |  |  |  |  | 0 |
Elmira Savings Bank | Core deposit intangibles |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Deposits |  |  | $ 8,000 |  |  |  |  | (7,970) |
OneGroup |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  |  | 100 |
Direct expenses |  |  |  |  |  |  |  | 500 |
Purchase price of acquisition |  |  |  |  |  |  |  | $ 3,500 |
Cash |  |  |  | $ 11,600 |  |  |  |  |
Customer list intangible | NuVantage Insurance Corp. |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Other intangibles |  |  |  |  |  | 1,400 |  |  |
Customer list intangible | Fringe Benefits Design of Minnesota, Inc |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Other intangibles |  |  |  |  | $ 14,000 |  |  |  |
Customer list intangible | Thomas Gregory Associates Insurance Brokers, Inc. |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Other intangibles |  |  |  | 10,900 |  |  |  |  |
Goodwill | NuVantage Insurance Corp. |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Goodwill |  |  |  |  |  | $ 1,400 |  |  |
Goodwill | Thomas Gregory Associates Insurance Brokers, Inc. |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Goodwill |  |  |  | $ 2,200 |  |  |  |  |
Subsequent events | Certain assets Of creative plan design limited |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |
Contingent consideration | $ 6,800 |  |  |  |  |  |  |  |
Fair value of contingent consideration at acquisition date | $ 3,900 |  |  |  |  |  |  |  |

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