Name:	nbtb_AmortizedCostsOfSecuritiesAvailableForSaleAndHeldToMaturityPledgedAsCollateralForRepurchaseAgreements
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This represents the available for sale and held to maturity securities that are pledged as collateral to secure public deposits and for other purposes required or permitted by law.

No definition available.

Name:	nbtb_AmortizedCostsOfSecuritiesAvailableForSaleAndHeldToMaturityPledgedToSecurePublicDeposits
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Gains from calls (requests of early payments) on debt securities which are classified as held-to-maturity securities.

No definition available.

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Amount of investment in debt security measured at amortized cost (held-to-maturity).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563

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- References

No definition available.

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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
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-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Subparagraph (c)
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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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-Publisher FASB
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