BORROWED FUNDS - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Outstanding advances of FRB	$ 335,659	$ 331,369
Outstanding amount	62,915	62,877
Financial Guarantee \| NHTB Capital Trust II and NHTB Capital Trust III
Debt Instrument [Line Items]
Debentures issued by variable interest entities	$ 20,600
LIBOR \| 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		288
FHLB advances
Debt Instrument [Line Items]
Outstanding amount	$ 285
Advances from the FHLB
Debt Instrument [Line Items]
Outstanding advances of FRB	322,925	318,000
Outstanding amount	2,585	2,588
Credit Facility, Secured, FHLB [Member]
Debt Instrument [Line Items]
Line of credit maintained	1,000
Line of credit outstanding	0	0
Credit Facility, Secured, FRB [Member]
Debt Instrument [Line Items]
Line of credit maintained	177,500
Line of credit outstanding	0	0
Credit Facility, Unsecured, Federal Funds [Member]
Debt Instrument [Line Items]
Line of credit maintained	50,000	50,000
Line of credit outstanding	$ 0	$ 0

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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

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