Debt Instrument, Call Date, Earliest Period

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

The calculated average balance outstanding for the year for all Federal Home Loan Bank advances as of the Balance Sheet date.

+ References

+ Details

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Period Type:	duration

- Definition

The calculated weighted average interest rate for Federal Home Loan Bank advances for the period ended as of the Balance Sheet date.

+ References

+ Details

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- Definition

The maximum balance outstanding at any month end during the period as of the Balance Sheet date.

+ References

+ Details

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Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82913245&loc=d3e12069-110248

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Period Type:	instant

- Definition

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.

+ References

+ Details

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- Definition

The carrying value as of the balance sheet date of the current portion 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(1))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Details

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BORROWED FUNDS - Narrative (Details) - USD ($)		1 Months Ended	12 Months Ended
BORROWED FUNDS - Narrative (Details) - USD ($)	Jan. 13, 2017	Apr. 30, 2008	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Average balance outstanding			$ 590,100,000	$ 368,400,000
Average interest rate for year			1.21%	0.80%
Short-term debt			$ 649,498,000	$ 394,480,000
Amount			180,223,000	142,116,000
Financial Guarantee \| NHTB Capital Trust II \| Lake Sunapee
Debt Instrument [Line Items]
Debentures issued by variable interest entities	$ 600,000
Financial Guarantee \| NHTB Capital Trust III \| Lake Sunapee
Debt Instrument [Line Items]
Debentures issued by variable interest entities	20,000,000
Subordinated debt \| Lake Sunapee
Debt Instrument [Line Items]
Principal amount of debt issued	$ 17,000,000
Fixed interest rate	6.75%
LIBOR \| Financial Guarantee \| Lake Sunapee
Debt Instrument [Line Items]
Interest rate margin	2.79%
Advances from the FHLB
Debt Instrument [Line Items]
Secured line of credit maintained			1,000,000
Short-term line of credit outstanding			0	0
Short-term debt			608,792,000	372,700,000
Amount			137,190,000	137,116,000
Federal Reserve Bank Advances
Debt Instrument [Line Items]
Secured line of credit maintained			117,100,000
Short-term debt			0	0
Federal Home Loan Bank Certificates and Obligations FHLB Callable Advances
Debt Instrument [Line Items]
Amount			27,000,000	17,000,000
Federal Home Loan Bank Certificates and Obligations FHLB Amortizing Advances
Debt Instrument [Line Items]
Amount			683,000	0
Subordinated borrowings
Debt Instrument [Line Items]
Amount			$ 38,033,000	$ 0
Maturity period (in years)		15 years
Principal amount of debt issued		$ 5,000,000
Earliest callable period without penalties		5 years
Effective interest rate			5.04%	4.41%
Subordinated borrowings \| LIBOR
Debt Instrument [Line Items]
Interest rate margin		3.45%
Federal Home Loan Bank of Boston
Debt Instrument [Line Items]
Maximum outstanding at any month end			$ 720,900,000	$ 427,100,000