XML 49 R38.htm IDEA: XBRL DOCUMENT
v3.5.0.2

Allowance for Loan Losses and Credit Quality of Loans, Impaired Loans (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015 | Dec. 31, 2015
Allowance for Loan Losses and Credit Quality of Loans [Abstract] |  |  |  |  |
Threshold balance for classified loans to be evaluated individually for impairment | $ 800 |  | $ 800 |  |
With an allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 37,389 |  | 37,389 |  | $ 27,168
Unpaid principal balance (legal) | 41,760 |  | 41,760 |  | 31,665
Related allowance | 3,372 |  | 3,372 |  | 2,005
Average recorded investment | 36,521 | $ 35,142 | 35,116 | $ 33,980 |
Interest income recognized | 251 | 269 | 731 | 694 |
Originated Loans [Member] |  |  |  |  |
With no related allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 27,488 |  | 27,488 |  | 21,296
Unpaid principal balance (legal) | 29,887 |  | 29,887 |  | 23,828
With an allowance recorded [Abstract] |  |  |  |  |
Average recorded investment | 35,316 | 25,693 | 33,911 | 24,252 |
Interest income recognized | 251 | 269 | 731 | 694 |
Originated Loans [Member] | Commercial Loans [Member] |  |  |  |  |
With no related allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 12,898 |  | 12,898 |  | 7,586
Unpaid principal balance (legal) | 13,497 |  | 13,497 |  | 8,606
With an allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 8,696 |  | 8,696 |  | 4,667
Unpaid principal balance (legal) | 10,552 |  | 10,552 |  | 6,516
Related allowance | 2,681 |  | 2,681 |  | 1,270
Originated Loans [Member] | Commercial Loans [Member] | Commercial [Member] |  |  |  |  |
With no related allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 2,174 |  | 2,174 |  | 2,244
Unpaid principal balance (legal) | 2,441 |  | 2,441 |  | 2,490
With an allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 1,014 |  | 1,014 |  | 457
Unpaid principal balance (legal) | 1,022 |  | 1,022 |  | 457
Related allowance | 555 |  | 555 |  | 300
Average recorded investment | 3,204 | 2,469 | 3,041 | 2,026 |
Interest income recognized | 0 | 42 | 0 | 128 |
Originated Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] |  |  |  |  |
With no related allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 8,469 |  | 8,469 |  | 3,165
Unpaid principal balance (legal) | 8,602 |  | 8,602 |  | 3,175
With an allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 7,476 |  | 7,476 |  | 4,210
Unpaid principal balance (legal) | 9,324 |  | 9,324 |  | 6,059
Related allowance | 2,035 |  | 2,035 |  | 970
Average recorded investment | 15,799 | 8,560 | 14,782 | 8,884 |
Interest income recognized | 48 | 42 | 122 | 124 |
Originated Loans [Member] | Commercial Loans [Member] | Agricultural [Member] |  |  |  |  |
With no related allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 133 |  | 133 |  | 576
Unpaid principal balance (legal) | 139 |  | 139 |  | 1,164
With an allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 50 |  | 50 |  | 0
Unpaid principal balance (legal) | 50 |  | 50 |  | 0
Related allowance | 37 |  | 37 |  | 0
Average recorded investment | 85 | 19 | 101 | 19 |
Interest income recognized | 0 | 0 | 1 | 1 |
Originated Loans [Member] | Commercial Loans [Member] | Agricultural Real Estate [Member] |  |  |  |  |
With no related allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 1,457 |  | 1,457 |  | 618
Unpaid principal balance (legal) | 1,583 |  | 1,583 |  | 744
With an allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 156 |  | 156 |  | 0
Unpaid principal balance (legal) | 156 |  | 156 |  | 0
Related allowance | 54 |  | 54 |  | 0
Average recorded investment | 935 | 626 | 742 | 630 |
Interest income recognized | 11 | 11 | 33 | 34 |
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member] |  |  |  |  |
With no related allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 665 |  | 665 |  | 983
Unpaid principal balance (legal) | 732 |  | 732 |  | 1,033
With an allowance recorded [Abstract] |  |  |  |  |
Average recorded investment | 743 | 1,003 | 882 | 952 |
Interest income recognized | 0 | 3 | 7 | 9 |
Originated Loans [Member] | Consumer Loans [Member] |  |  |  |  |
With no related allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 8,502 |  | 8,502 |  | 7,693
Unpaid principal balance (legal) | 9,480 |  | 9,480 |  | 8,595
Originated Loans [Member] | Consumer Loans [Member] | Indirect [Member] |  |  |  |  |
With no related allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 7 |  | 7 |  | 12
Unpaid principal balance (legal) | 17 |  | 17 |  | 21
With an allowance recorded [Abstract] |  |  |  |  |
Average recorded investment | 8 | 20 | 9 | 14 |
Interest income recognized | 0 | 0 | 0 | 0 |
Originated Loans [Member] | Consumer Loans [Member] | Home Equity [Member] |  |  |  |  |
With no related allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 8,495 |  | 8,495 |  | 7,681
Unpaid principal balance (legal) | 9,463 |  | 9,463 |  | 8,574
With an allowance recorded [Abstract] |  |  |  |  |
Average recorded investment | 8,401 | 7,432 | 8,207 | 6,869 |
Interest income recognized | 116 | 134 | 357 | 298 |
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] |  |  |  |  |
With no related allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 0 |  | 0 |  | 0
Unpaid principal balance (legal) | 0 |  | 0 |  | 0
With an allowance recorded [Abstract] |  |  |  |  |
Average recorded investment | 0 | 0 | 0 | 1 |
Interest income recognized | 0 | 0 | 0 | 0 |
Originated Loans [Member] | Residential Real Estate Mortgages [Member] |  |  |  |  |
With no related allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 6,088 |  | 6,088 |  | 6,017
Unpaid principal balance (legal) | 6,910 |  | 6,910 |  | 6,627
With an allowance recorded [Abstract] |  |  |  |  |
Average recorded investment | 6,141 | 5,564 | 6,147 | 4,857 |
Interest income recognized | 76 | 37 | 211 | 100 |
Acquired Loans [Member] |  |  |  |  |
With an allowance recorded [Abstract] |  |  |  |  |
Average recorded investment | 1,205 | 9,449 | 1,205 | 9,728 |
Interest income recognized | 0 | 0 | 0 | 0 |
Acquired Loans [Member] | Commercial Loans [Member] |  |  |  |  |
With an allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 1,205 |  | 1,205 |  | 1,205
Unpaid principal balance (legal) | 1,321 |  | 1,321 |  | 1,321
Related allowance | 691 |  | 691 |  | 735
Acquired Loans [Member] | Commercial Loans [Member] | Commercial [Member] |  |  |  |  |
With an allowance recorded [Abstract] |  |  |  |  |
Average recorded investment | 0 | 2,531 | 0 | 2,658 |
Interest income recognized | 0 | 0 | 0 | 0 |
Acquired Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] |  |  |  |  |
With an allowance recorded [Abstract] |  |  |  |  |
Recorded investment balance (book) | 1,205 |  | 1,205 |  | 1,205
Unpaid principal balance (legal) | 1,321 |  | 1,321 |  | 1,321
Related allowance | 691 |  | 691 |  | $ 735
Average recorded investment | 1,205 | 6,918 | 1,205 | 7,070 |
Interest income recognized | $ 0 | $ 0 | $ 0 | $ 0 |

X
- References No definition available. + Details
Name: | nbtb_AllowanceForLoanLossesAndCreditQualityOfLoansAbstract
Namespace Prefix: | nbtb_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The threshold balance for classified loans to be individually evaluated for impairment. + References No definition available. + Details
Name: | nbtb_FinancingReceivableClassifiedGradingThresholdBalanceForClassifiedLoansToBeIndividuallyEvaluatedForImpairment
Namespace Prefix: | nbtb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | nbtb_WithAnAllowanceRecordedAbstract
Namespace Prefix: | nbtb_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | nbtb_WithNoAllowanceRecordedAbstract
Namespace Prefix: | nbtb_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableAverageRecordedInvestment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableInterestIncomeAccrualMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableRecordedInvestment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of allowance for credit losses related to recorded investment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Recorded Investment -URI http://asc.fasb.org/extlink&oid=65880944 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableRelatedAllowance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of investment in impaired financing receivables for which there is no related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of investment in impaired financing receivables for which there is a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=nbtb_OriginatedLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=nbtb_CommercialFinancingReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_RealEstateLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=nbtb_AgriculturalFinancingReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=nbtb_AgriculturalRealEstateFinancingReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=nbtb_SmallBusinessFinancingReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=nbtb_IndirectFinancingReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=nbtb_HomeEquityFinancingReceivablesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=nbtb_DirectFinancingReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=nbtb_AcquiredLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |