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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Past Due Status of Modifications under ASU 2022-02 (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	$ 2,028,954	$ 1,972,664
Total Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	12,691	14,360
30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	4,692	9,562
60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	2,231	943
90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	5,768	3,855
Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	2,016,263	1,958,304
Commercial and industrial
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	289,266	264,396
Commercial and industrial | Total Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	1,249	1,237
Commercial and industrial | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	144	1,196
Commercial and industrial | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	232	31
Commercial and industrial | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	873	10
Commercial and industrial | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	288,017	263,159
Residential Mortgages
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	274,099	277,992
Residential Mortgages | Total Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	3,408	3,030
Residential Mortgages | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	2,293	2,244
Residential Mortgages | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	341	201
Residential Mortgages | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	774	585
Residential Mortgages | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	270,691	274,962
Commercial Mortgages
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	1,174,939	1,122,925
Commercial Mortgages | Commercial mortgages, other
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	1,036,229	984,038
Commercial Mortgages | Total Past Due | Commercial mortgages, other
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	3,150	1,386
Commercial Mortgages | 30 - 59 Days Past Due | Commercial mortgages, other
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	0	1,022
Commercial Mortgages | 60 - 89 Days Past Due | Commercial mortgages, other
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	1,014	103
Commercial Mortgages | 90 Days or More Past Due | Commercial mortgages, other
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	2,136	261
Commercial Mortgages | Loans Not Past Due | Commercial mortgages, other
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	1,033,079	982,652
Consumer Loans
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	290,650	307,351
Consumer Loans | Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	92,449	87,056
Consumer Loans | Total Past Due | Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	852	914
Consumer Loans | 30 - 59 Days Past Due | Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	437	461
Consumer Loans | 60 - 89 Days Past Due | Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	192	87
Consumer Loans | 90 Days or More Past Due | Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	223	366
Consumer Loans | Loans Not Past Due | Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	91,597	86,142
Restructured Debt | Total Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	561	3,159
Restructured Debt | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	0	0
Restructured Debt | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	0	0
Restructured Debt | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	440	0
Restructured Debt | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	121	3,159
Restructured Debt | Commercial and industrial | Total Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	121
Restructured Debt | Commercial and industrial | Total Past Due | Commercial and Agricultural Sector
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees		875
Restructured Debt | Commercial and industrial | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	0
Restructured Debt | Commercial and industrial | 30 - 59 Days Past Due | Commercial and Agricultural Sector
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees		0
Restructured Debt | Commercial and industrial | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	0
Restructured Debt | Commercial and industrial | 60 - 89 Days Past Due | Commercial and Agricultural Sector
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees		0
Restructured Debt | Commercial and industrial | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	0
Restructured Debt | Commercial and industrial | 90 Days or More Past Due | Commercial and Agricultural Sector
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees		0
Restructured Debt | Commercial and industrial | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	121
Restructured Debt | Commercial and industrial | Loans Not Past Due | Commercial and Agricultural Sector
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees		875
Restructured Debt | Residential Mortgages | Total Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	440
Restructured Debt | Residential Mortgages | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	0
Restructured Debt | Residential Mortgages | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	0
Restructured Debt | Residential Mortgages | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	440
Restructured Debt | Residential Mortgages | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees	$ 0
Restructured Debt | Commercial Mortgages | Total Past Due | Commercial mortgages, other
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees			$ 2,167
Restructured Debt | Commercial Mortgages | 30 - 59 Days Past Due | Commercial mortgages, other
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees			0
Restructured Debt | Commercial Mortgages | 60 - 89 Days Past Due | Commercial mortgages, other
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees			0
Restructured Debt | Commercial Mortgages | 90 Days or More Past Due | Commercial mortgages, other
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees			0
Restructured Debt | Commercial Mortgages | Loans Not Past Due | Commercial mortgages, other
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees			$ 2,167
Restructured Debt | Consumer Loans | Total Past Due | Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees		117
Restructured Debt | Consumer Loans | 30 - 59 Days Past Due | Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees		0
Restructured Debt | Consumer Loans | 60 - 89 Days Past Due | Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees		0
Restructured Debt | Consumer Loans | 90 Days or More Past Due | Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees		0
Restructured Debt | Consumer Loans | Loans Not Past Due | Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Loans, net of deferred loan fees		$ 117

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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