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ACQUISITIONS (Details) shares in Thousands, $ in Thousands |  |  |  |  |  |  |  | 1 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Nov. 01, 2022 USD ($) | May 13, 2022 USD ($) item | Jan. 01, 2022 USD ($) | Aug. 02, 2021 USD ($) | Jul. 01, 2021 USD ($) | Jun. 01, 2021 USD ($) | Jun. 12, 2020 USD ($) country Office shares | Dec. 31, 2022 USD ($) country | Jun. 30, 2022 USD ($) | Sep. 30, 2022 USD ($) | Dec. 31, 2022 USD ($) country | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Purchase price of acquisition |  |  |  |  |  |  |  |  |  |  | $ 85,656 |  |
Loans |  |  |  |  |  |  |  | $ 436,954 |  |  | 436,954 |  |
Investment securities |  |  |  |  |  |  |  | 11,305 |  |  | 11,305 |  |
Deposits |  |  |  |  |  |  |  | 522,295 |  |  | 522,295 |  |
Goodwill |  |  |  |  |  |  |  | $ 841,841 |  |  | 841,841 | $ 799,109 | $ 793,708
Provision for credit losses |  |  |  |  |  |  |  |  |  |  | 14,773 | (8,839) | 14,212
Number of insurance agencies |  |  | 3 |  |  |  |  |  |  |  |  |  |
Other intangibles |  |  | $ 2,500 |  |  |  |  |  |  |  |  |  |
Contingent consideration |  |  |  |  |  |  |  |  |  |  | 0 |  |
Cash |  |  |  |  |  |  |  |  |  |  | 668 | 29,329 | (34,360)
Acquisition-related contingent consideration adjustment |  |  |  |  |  |  |  |  |  |  | $ (300) | 200 | 0
Upstate New York |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Number of counties where the bank has facilities | country |  |  |  |  |  |  |  | 42 |  |  | 42 |  |
Core deposit intangibles |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Deposits |  |  |  |  |  |  |  | $ 7,970 |  |  | $ 7,970 |  |
NuVantage Insurance Corp. |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue earned |  |  |  |  |  |  |  |  |  |  | 1,300 | 700 |
Direct expenses |  |  |  |  |  |  |  |  |  |  | 1,300 | 600 |
Goodwill |  |  |  |  |  |  |  | 42,669 |  |  | 42,669 |  |
Cash |  |  |  |  |  | $ 2,900 |  |  |  |  |  |  |
NuVantage Insurance Corp. | Minimum | Adjusted level of retained revenue |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration, measurement input 2 |  |  |  |  |  |  |  | $ 4,900 |  |  | 4,900 |  |
Fringe Benefits Design of Minnesota, Inc |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue earned |  |  |  |  |  |  |  |  |  |  | 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 |  |  |  |  | 3 years |  |  |  |  |  |  |  |
Contingent consideration |  |  |  |  | $ 1,400 |  |  |  |  |  |  |  |
Cash |  |  |  |  | $ 15,400 |  |  |  |  |  |  |  |
Contingent consideration, measurement input |  |  |  |  | 0.0105 |  |  | 0.0609 |  |  | 0.0609 |  |
Acquisition-related contingent consideration adjustment |  |  |  |  |  |  |  |  | $ 100 |  | $ 500 |  |
Fair value contingent consideration adjustment |  |  |  |  |  |  |  | $ 400 |  |  | 1,100 |  |
Increase (decrease) in goodwill as a result of fair value adjustment |  |  |  |  |  |  |  |  |  |  | (3,600) |  |
Fringe Benefits Design of Minnesota, Inc | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration |  |  |  |  | $ 2,700 |  |  |  |  |  | 2,700 |  |
Fringe Benefits Design of Minnesota, Inc | Maximum | Adjusted level of retained revenue |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration, measurement input 2 |  |  |  |  | 5,800 |  |  | $ 5,100 |  |  | 5,100 |  |
Fringe Benefits Design of Minnesota, Inc | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration |  |  |  |  | 0 |  |  |  |  |  | 0 |  |
Fringe Benefits Design of Minnesota, Inc | Minimum | Adjusted level of retained revenue |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration, measurement input 2 |  |  |  |  | 5,600 |  |  |  |  |  |  |  |
Steuben Trust Corporation |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue earned |  |  |  |  |  |  |  |  |  |  | 11,400 | 13,100 | 7,700
Direct expenses |  |  |  |  |  |  |  |  |  |  | 4,800 | 5,100 | 2,600
Purchase price of acquisition |  |  |  |  |  |  |  |  |  |  |  |  | 98,555
Assets acquired |  |  |  |  |  |  | $ 607,800 |  |  |  |  |  |
Loans |  |  |  |  |  |  | 339,700 |  |  |  |  |  | 339,017
Investment securities |  |  |  |  |  |  | 180,500 |  |  |  |  |  | 180,497
Deposits |  |  |  |  |  |  | (516,300) |  |  |  |  |  | 516,274
Goodwill |  |  |  |  |  |  | 20,000 |  |  |  |  |  | 19,981
Contingent consideration |  |  |  |  |  |  |  |  |  |  |  |  | 0
Cash |  |  |  |  |  |  | $ 98,600 |  |  |  |  |  |
Issuance of common shares (in shares) | shares |  |  |  |  |  |  | 1,360 |  |  |  |  |  |
Issuance of common shares |  |  |  |  |  |  | $ 21,600 |  |  |  |  |  |
Increase (decrease) in other liabilities as a result of reclassification and adjustment |  |  |  |  |  |  |  |  |  |  | (100) |  |
Increase (decrease) in goodwill as a result of fair value adjustment |  |  |  |  |  |  |  |  |  | $ (4,900) |  |  |
Steuben Trust Corporation | Western New York State |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Number of new counties where the bank has extended footprints | country |  |  |  |  |  |  | 2 |  |  |  |  |  |
Number of counties where the bank has facilities | country |  |  |  |  |  |  | 4 |  |  |  |  |  |
Number of branch locations | Office |  |  |  |  |  |  | 11 |  |  |  |  |  |
Steuben Trust Corporation | Core deposit intangibles |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Deposits |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,928
Thomas Gregory Associates Insurance Brokers, Inc. |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue earned |  |  |  |  |  |  |  |  |  |  | 3,100 | 600 |
Direct expenses |  |  |  |  |  |  |  |  |  |  | 1,800 | $ 600 |
Period considered for additional consideration based on future retained revenue |  |  |  | 3 years |  |  |  |  |  |  |  |  |
Contingent consideration |  |  |  | $ 1,500 |  |  |  |  |  |  |  |  |
Acquisition-related contingent consideration adjustment |  |  |  |  |  |  |  |  | 500 |  | 300 |  |
Fair value contingent consideration adjustment |  |  |  |  |  |  |  |  | $ 200 |  | 1,700 |  |
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 |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue earned |  |  |  | $ 3,800 |  |  |  |  |  |  |  |  |
Contingent consideration |  |  |  |  |  |  |  |  |  |  | $ 3,400 |  |
Cash |  |  |  | $ 3,400 |  |  |  |  |  |  |  |  |
Contingent consideration, measurement input |  |  |  | 0.0109 |  |  |  | 6.21 |  |  | 6.21 |  |
Thomas Gregory Associates Insurance Brokers, Inc. | Maximum | Adjusted level of retained revenue |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration, measurement input 2 |  |  |  |  |  |  |  | $ 3,200 |  |  | $ 3,200 |  |
Thomas Gregory Associates Insurance Brokers, Inc. | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue earned |  |  |  | $ 2,300 |  |  |  |  |  |  |  |  |
Contingent consideration |  |  |  |  |  |  |  |  |  |  | $ 0 |  |
Cash |  |  |  | $ 0 |  |  |  |  |  |  |  |  |
Contingent consideration, measurement input |  |  |  | 0.0082 |  |  |  | 5.87 |  |  | 5.87 |  |
Thomas Gregory Associates Insurance Brokers, Inc. | Minimum | Adjusted level of retained revenue |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration, measurement input 2 |  |  |  |  |  |  |  | $ 3,100 |  |  | $ 3,100 |  |
Elmira transaction |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue earned |  |  |  |  |  |  |  |  |  |  | 12,100 |  |
Direct expenses |  |  |  |  |  |  |  |  |  |  | 3,100 |  |
Purchase price of acquisition |  | $ 82,200 |  |  |  |  |  |  |  |  | 82,179 |  |
Number of county | item |  | 5 |  |  |  |  |  |  |  |  |  |  |
Assets acquired |  | $ 583,400 |  |  |  |  |  |  |  |  |  |  |
Loans |  | 437,000 |  |  |  |  |  | 436,954 |  |  | 436,954 |  |
Investment securities |  | 11,300 |  |  |  |  |  | 11,305 |  |  | 11,305 |  |
Deposits |  | 522,300 |  |  |  |  |  | 522,295 |  |  | 522,295 |  |
Goodwill |  | 42,200 |  |  |  |  |  | 42,220 |  |  | 42,220 |  |
Provision for credit losses |  | 3,900 |  |  |  |  |  |  |  |  |  |  |
Contingent consideration |  |  |  |  |  |  |  |  |  |  | 0 |  |
Elmira transaction | Core deposit intangibles |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Deposits |  | $ 8,000 |  |  |  |  |  | $ 7,970 |  |  | 7,970 |  |
OneGroup |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue earned |  |  |  |  |  |  |  |  |  |  | 900 |  |
Direct expenses |  |  |  |  |  |  |  |  |  |  | 400 |  |
Purchase price of acquisition |  |  | $ 2,500 |  |  |  |  |  |  |  |  |  |
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 |  |  |  |  |  |  |  |  |
Certain assets of JMD Associates |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Cash paid | $ 1,000 |  |  |  |  |  |  |  |  |  |  |  |
Revenue earned |  |  |  |  |  |  |  |  |  |  | 100 |  |
Direct expenses |  |  |  |  |  |  |  |  |  |  | $ 100 |  |
Certain assets of JMD Associates | Noncompete agreement |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Cash paid | 100 |  |  |  |  |  |  |  |  |  |  |  |
Certain assets of JMD Associates | Customer list intangible |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Cash paid | 400 |  |  |  |  |  |  |  |  |  |  |  |
Certain assets of JMD Associates | Goodwill |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |
Cash paid | $ 500 |  |  |  |  |  |  |  |  |  |  |  |

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