BORROWED FUNDS - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Outstanding advances of BTFP	$ 269,161	$ 270,765
Outstanding amount	60,777	60,740
Financial Guarantee \| NHTB Capital Trust II and NHTB Capital Trust III
Debt Instrument [Line Items]
Debentures issued by variable interest entities	$ 20,600
SOFR \| Financial Guarantee
Debt Instrument [Line Items]
Interest rate margin	2.79%
Callable Advances
Debt Instrument [Line Items]
Outstanding amount		0
Amortizing Advances
Debt Instrument [Line Items]
Outstanding amount		279
FHLB advances
Debt Instrument [Line Items]
Outstanding amount	$ 276
Advances from the FHLB
Debt Instrument [Line Items]
Short-term FHLB variable rate	0.00%
Outstanding advances of BTFP	$ 196,000	232,300
Outstanding amount	$ 276	279
Long-term FHLB variable rate	0.00%
Credit Facility, Secured, FHLB
Debt Instrument [Line Items]
Line of credit maintained	$ 1,000
Line of credit outstanding	$ 0	0
Federal Reserve Bank Advances
Debt Instrument [Line Items]
Fixed interest rate	4.76%
Outstanding advances of BTFP	$ 65,000	30,000
Existing Advance
Debt Instrument [Line Items]
Fixed interest rate	4.85%
Prepaid existing advance	$ 30,000
New Advance
Debt Instrument [Line Items]
Fixed interest rate	4.76%
New advance	$ 65,000
Credit Facility, Secured, FRB
Debt Instrument [Line Items]
Line of credit maintained	155,900	156,600
Credit Facility, Unsecured, Federal Funds
Debt Instrument [Line Items]
Line of credit maintained	50,000	50,000
Line of credit outstanding	$ 0	$ 0

Variable interest rate of long term debt.

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Face (par) amount of debt instrument at time of issuance.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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