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

Allowance for Loan Losses and Credit Quality of Loans, Troubled Debt Restructurings (Details) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2016 USD ($) Contract | Jun. 30, 2015 USD ($) Contract | Jun. 30, 2016 USD ($) Contract | Jun. 30, 2015 USD ($) Contract
Financing Receivable, Modifications [Line Items] |  |  |  |
Period of sustained repayment performance for nonperforming TDRs to be returned to performing status |  |  | 6 months |
Number of contracts | Contract | 4 | 20 | 20 | 48
Pre-modification outstanding recorded investment | $ 226 | $ 2,796 | $ 1,792 | $ 4,645
Post-modification outstanding recorded investment | $ 224 | $ 3,239 | $ 1,595 | $ 5,099
Number of TDR loans with subsequent default | Contract |  |  | 1 | 4
Outstanding recorded investment on TDR loans with subsequent default |  |  | $ 175 | $ 233
Commercial Loans [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract |  | 2 |  | 2
Pre-modification outstanding recorded investment |  | $ 1,355 |  | $ 1,355
Post-modification outstanding recorded investment |  | $ 1,341 |  | $ 1,341
Commercial Loans [Member] | Commercial [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract |  | 1 |  | 1
Pre-modification outstanding recorded investment |  | $ 1,165 |  | $ 1,165
Post-modification outstanding recorded investment |  | $ 1,165 |  | $ 1,165
Commercial Loans [Member] | Business Banking [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract |  | 1 |  | 1
Pre-modification outstanding recorded investment |  | $ 190 |  | $ 190
Post-modification outstanding recorded investment |  | $ 176 |  | $ 176
Consumer Loans [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 2 | 12 | 14 | 31
Pre-modification outstanding recorded investment | $ 74 | $ 1,071 | $ 1,109 | $ 2,218
Post-modification outstanding recorded investment | $ 73 | $ 1,128 | $ 1,017 | $ 2,236
Consumer Loans [Member] | Home Equity [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 2 | 12 | 14 | 31
Pre-modification outstanding recorded investment | $ 74 | $ 1,071 | $ 1,109 | $ 2,218
Post-modification outstanding recorded investment | $ 73 | $ 1,128 | $ 1,017 | $ 2,236
Number of TDR loans with subsequent default | Contract |  |  | 0 | 4
Outstanding recorded investment on TDR loans with subsequent default |  |  | $ 0 | $ 233
Residential Real Estate Mortgages [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 2 | 6 | 6 | 15
Pre-modification outstanding recorded investment | $ 152 | $ 370 | $ 683 | $ 1,072
Post-modification outstanding recorded investment | $ 151 | $ 770 | $ 578 | $ 1,522
Number of TDR loans with subsequent default | Contract |  |  | 1 | 0
Outstanding recorded investment on TDR loans with subsequent default |  |  | $ 175 | $ 0

X
- Definition Period of sustained repayment performance for nonperforming TDRs to be returned to performing status. + References No definition available. + Details
Name: | nbtb_PeriodOfSustainedRepaymentPerformanceForNonperformingTdrsToBeReturnedToPerformingStatus
Namespace Prefix: | nbtb_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- 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
Name: | us-gaap_FinancingReceivableModificationsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953676-111524 + Details
Name: | us-gaap_FinancingReceivableModificationsNumberOfContracts2
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Post-modification amount of investment in financing receivables modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953676-111524 + Details
Name: | us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Pre-modification amount of investment in financing receivables modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953676-111524 + Details
Name: | us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953682-111524 + Details
Name: | us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953682-111524 + Details
Name: | us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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=nbtb_BusinessBankingFinancingReceivableMember
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_HomeEquityFinancingReceivablesMember
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: |