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Amount of financing receivables processed.

No definition available.

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Number of financing receivables processed.

No definition available.

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Represents the principal repayment term of the financing receivable, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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Represents the draw term of the financing receivable, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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Amount of financing receivables modified related to COVID-19.

No definition available.

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This element represents the percentage of the appraised value or purchase price of a property for the originated amounts of loans.

No definition available.

Name:	nbtb_LoanOriginationAmountPercentageOfAppraisedValueOrPurchasePriceOfProperty
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This element represents the percentage of the equity in a property for the originated amounts of loans.

No definition available.

Name:	nbtb_LoanOriginationAmountPercentageOfEquityInProperty
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No definition available.

Name:	nbtb_LoansReceivableAbstract
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The amount of noninterest income out-of-scope of Topic 606.

No definition available.

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No definition available.

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Period of sustained repayment performance for nonperforming TDRs to be returned to performing status, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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Represents expiration period of standby letters of credit, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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The threshold period past due for a loan to be considered nonperforming, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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The threshold period past due for a loan to be written off, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	nbtb_ThresholdPeriodPastDueForLoansToBeWrittenOff
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No definition available.

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The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

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No definition available.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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