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v3.3.1.900

Allowance for Loan Losses and Credit Quality of Loans (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2015 USD ($) Segment
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Loan portfolio segments | Segment | 3
Commercial Loans [Member] | Commercial Real Estate [Member] | Maximum [Member] |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Real estate loan amount, percentage of appraised value or purchase price of the property | 80.00%
Commercial Loans [Member] | Agricultural Real Estate [Member] | Maximum [Member] |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Real estate loan amount, percentage of appraised value or purchase price of the property | 75.00%
Commercial Loans [Member] | Business Banking [Member] |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Business banking loans, maximum amount available | $ | $ 500
Consumer Loans [Member] | Indirect [Member] |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Percentage of automobile financing to indirect relationships with dealers | 70.00%
Consumer Loans [Member] | Indirect [Member] | Minimum [Member] |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Principal repayment term of loan | 3 years
Consumer Loans [Member] | Indirect [Member] | Maximum [Member] |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Principal repayment term of loan | 6 years
Consumer Loans [Member] | Home Equity [Member] | Maximum [Member] |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Home equity loan amount, percentage of equity in home | 85.00%
Consumer Loans [Member] | Direct [Member] | Minimum [Member] |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Principal repayment term of loan | 1 year
Consumer Loans [Member] | Direct [Member] | Maximum [Member] |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Principal repayment term of loan | 10 years
Residential Real Estate Mortgages [Member] | Maximum [Member] |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Real estate loan amount, percentage of appraised value or purchase price of the property | 85.00%

X
- Definition Represents the repayment term of the debt instrument. + References No definition available. + Details
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Namespace Prefix: | nbtb_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition This element represents the percentage of the equity in home, for the originated amounts of home equity loans. + References No definition available. + Details
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Namespace Prefix: | nbtb_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

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- Definition This element represents the percentage of the appraised value or purchase price of a property, for the originated amounts of real estate loans. + References No definition available. + Details
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Namespace Prefix: | nbtb_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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- Definition This element represents the number of portfolio segments within the loan portfolio. + References No definition available. + Details
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Namespace Prefix: | nbtb_
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Balance Type: | na
Period Type: | duration

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- Definition Represents the percentage of automobile financing to indirect relationships the Company maintains with dealers. + References No definition available. + Details
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Namespace Prefix: | nbtb_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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- Definition This element represents the maximum loan amount available for small business customers. + References No definition available. + Details
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Namespace Prefix: | nbtb_
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Balance Type: | debit
Period Type: | instant

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- Details
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- Details
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