XML 49 R38.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Allowance for Loan Losses and Credit Quality of Loans, Past Due Loans (Details) - USD ($) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2017 | Dec. 31, 2016
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Minimum number of days past due for nonaccrual loan status | 90 days |
Total past due accruing | $ 40,845 | $ 39,485
Nonaccrual | 23,453 | 35,712
Current | 6,402,636 | 6,122,860
Recorded total loans | 6,466,934 | 6,198,057
31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 30,768 | 28,717
61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 6,689 | 5,958
Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 3,388 | 4,810
Commercial Loans [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Recorded total loans | 2,962,287 | 2,786,002
Consumer Loans [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Recorded total loans | 2,202,070 | 2,149,441
Residential Real Estate Mortgages [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Recorded total loans | 1,302,577 | 1,262,614
Originated Loans [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 39,006 | 37,811
Nonaccrual | 20,256 | 30,077
Current | 5,985,849 | 5,630,075
Recorded total loans | 6,045,111 | 5,697,963
Originated Loans [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 29,385 | 27,488
Originated Loans [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 6,280 | 5,870
Originated Loans [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 3,341 | 4,453
Originated Loans [Member] | Commercial Loans [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 3,813 | 1,965
Nonaccrual | 9,139 | 18,292
Current | 2,752,891 | 2,528,127
Recorded total loans | 2,765,843 | 2,548,384
Originated Loans [Member] | Commercial Loans [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 3,566 | 1,642
Originated Loans [Member] | Commercial Loans [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 247 | 323
Originated Loans [Member] | Commercial Loans [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Originated Loans [Member] | Commercial Loans [Member] | Commercial [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 157 | 38
Nonaccrual | 430 | 2,964
Current | 732,535 | 650,568
Recorded total loans | 733,122 | 653,570
Originated Loans [Member] | Commercial Loans [Member] | Commercial [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 1 | 33
Originated Loans [Member] | Commercial Loans [Member] | Commercial [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 156 | 5
Originated Loans [Member] | Commercial Loans [Member] | Commercial [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Originated Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 1,274 | 0
Nonaccrual | 2,020 | 7,935
Current | 1,477,265 | 1,343,854
Recorded total loans | 1,480,559 | 1,351,789
Originated Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 1,274 | 0
Originated Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Originated Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Originated Loans [Member] | Commercial Loans [Member] | Agricultural [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Nonaccrual | 391 | 730
Current | 34,448 | 37,186
Recorded total loans | 34,839 | 37,916
Originated Loans [Member] | Commercial Loans [Member] | Agricultural [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Originated Loans [Member] | Commercial Loans [Member] | Agricultural [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Originated Loans [Member] | Commercial Loans [Member] | Agricultural [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Originated Loans [Member] | Commercial Loans [Member] | Agricultural Real Estate [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 234 | 0
Nonaccrual | 1,658 | 1,803
Current | 33,499 | 30,619
Recorded total loans | 35,391 | 32,422
Originated Loans [Member] | Commercial Loans [Member] | Agricultural Real Estate [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 234 | 0
Originated Loans [Member] | Commercial Loans [Member] | Agricultural Real Estate [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Originated Loans [Member] | Commercial Loans [Member] | Agricultural Real Estate [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 2,148 | 1,927
Nonaccrual | 4,640 | 4,860
Current | 475,144 | 465,900
Recorded total loans | 481,932 | 472,687
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 2,057 | 1,609
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 91 | 318
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Originated Loans [Member] | Consumer Loans [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 30,538 | 31,543
Nonaccrual | 4,937 | 5,103
Current | 2,118,609 | 2,049,790
Recorded total loans | 2,154,084 | 2,086,436
Originated Loans [Member] | Consumer Loans [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 22,007 | 23,121
Originated Loans [Member] | Consumer Loans [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 5,787 | 5,375
Originated Loans [Member] | Consumer Loans [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 2,744 | 3,047
Originated Loans [Member] | Consumer Loans [Member] | Indirect [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 26,319 | 25,937
Nonaccrual | 2,069 | 2,145
Current | 1,602,890 | 1,538,593
Recorded total loans | 1,631,278 | 1,566,675
Originated Loans [Member] | Consumer Loans [Member] | Indirect [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 18,755 | 19,253
Originated Loans [Member] | Consumer Loans [Member] | Indirect [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 5,112 | 4,185
Originated Loans [Member] | Consumer Loans [Member] | Indirect [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 2,452 | 2,499
Originated Loans [Member] | Consumer Loans [Member] | Home Equity [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 3,774 | 5,009
Nonaccrual | 2,790 | 2,851
Current | 452,189 | 448,797
Recorded total loans | 458,753 | 456,657
Originated Loans [Member] | Consumer Loans [Member] | Home Equity [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 2,933 | 3,416
Originated Loans [Member] | Consumer Loans [Member] | Home Equity [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 628 | 1,065
Originated Loans [Member] | Consumer Loans [Member] | Home Equity [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 213 | 528
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 445 | 597
Nonaccrual | 78 | 107
Current | 63,530 | 62,400
Recorded total loans | 64,053 | 63,104
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 319 | 452
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 47 | 125
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 79 | 20
Originated Loans [Member] | Residential Real Estate Mortgages [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 4,655 | 4,303
Nonaccrual | 6,180 | 6,682
Current | 1,114,349 | 1,052,158
Recorded total loans | 1,125,184 | 1,063,143
Originated Loans [Member] | Residential Real Estate Mortgages [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 3,812 | 2,725
Originated Loans [Member] | Residential Real Estate Mortgages [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 246 | 172
Originated Loans [Member] | Residential Real Estate Mortgages [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 597 | 1,406
Acquired Loans [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 1,839 | 1,674
Nonaccrual | 3,197 | 5,635
Current | 416,787 | 492,785
Recorded total loans | 421,823 | 500,094
Acquired Loans [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 1,383 | 1,229
Acquired Loans [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 409 | 88
Acquired Loans [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 47 | 357
Acquired Loans [Member] | Commercial Loans [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 630 | 236
Nonaccrual | 1,274 | 2,695
Current | 194,540 | 234,687
Recorded total loans | 196,444 | 237,618
Acquired Loans [Member] | Commercial Loans [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 355 | 236
Acquired Loans [Member] | Commercial Loans [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 275 | 0
Acquired Loans [Member] | Commercial Loans [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Acquired Loans [Member] | Commercial Loans [Member] | Commercial [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Nonaccrual | 0 | 0
Current | 39,037 | 49,447
Recorded total loans | 39,037 | 49,447
Acquired Loans [Member] | Commercial Loans [Member] | Commercial [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Acquired Loans [Member] | Commercial Loans [Member] | Commercial [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Acquired Loans [Member] | Commercial Loans [Member] | Commercial [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Acquired Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Nonaccrual | 501 | 1,891
Current | 112,810 | 135,398
Recorded total loans | 113,311 | 137,289
Acquired Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Acquired Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Acquired Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Acquired Loans [Member] | Commercial Loans [Member] | Business Banking [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 630 | 236
Nonaccrual | 773 | 804
Current | 42,693 | 49,842
Recorded total loans | 44,096 | 50,882
Acquired Loans [Member] | Commercial Loans [Member] | Business Banking [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 355 | 236
Acquired Loans [Member] | Commercial Loans [Member] | Business Banking [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 275 | 0
Acquired Loans [Member] | Commercial Loans [Member] | Business Banking [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 0
Acquired Loans [Member] | Consumer Loans [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 412 | 474
Nonaccrual | 198 | 304
Current | 47,376 | 62,227
Recorded total loans | 47,986 | 63,005
Acquired Loans [Member] | Consumer Loans [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 368 | 384
Acquired Loans [Member] | Consumer Loans [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 34 | 60
Acquired Loans [Member] | Consumer Loans [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 10 | 30
Acquired Loans [Member] | Consumer Loans [Member] | Indirect [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 40 | 105
Nonaccrual | 30 | 47
Current | 2,084 | 8,541
Recorded total loans | 2,154 | 8,693
Acquired Loans [Member] | Consumer Loans [Member] | Indirect [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 29 | 100
Acquired Loans [Member] | Consumer Loans [Member] | Indirect [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 8 | 5
Acquired Loans [Member] | Consumer Loans [Member] | Indirect [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 3 | 0
Acquired Loans [Member] | Consumer Loans [Member] | Home Equity [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 307 | 337
Nonaccrual | 160 | 237
Current | 42,510 | 50,553
Recorded total loans | 42,977 | 51,127
Acquired Loans [Member] | Consumer Loans [Member] | Home Equity [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 307 | 254
Acquired Loans [Member] | Consumer Loans [Member] | Home Equity [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 53
Acquired Loans [Member] | Consumer Loans [Member] | Home Equity [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 0 | 30
Acquired Loans [Member] | Consumer Loans [Member] | Direct [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 65 | 32
Nonaccrual | 8 | 20
Current | 2,782 | 3,133
Recorded total loans | 2,855 | 3,185
Acquired Loans [Member] | Consumer Loans [Member] | Direct [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 32 | 30
Acquired Loans [Member] | Consumer Loans [Member] | Direct [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 26 | 2
Acquired Loans [Member] | Consumer Loans [Member] | Direct [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 7 | 0
Acquired Loans [Member] | Residential Real Estate Mortgages [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 797 | 964
Nonaccrual | 1,725 | 2,636
Current | 174,871 | 195,871
Recorded total loans | 177,393 | 199,471
Acquired Loans [Member] | Residential Real Estate Mortgages [Member] | 31-60 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 660 | 609
Acquired Loans [Member] | Residential Real Estate Mortgages [Member] | 61-90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | 100 | 28
Acquired Loans [Member] | Residential Real Estate Mortgages [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |
Financing Receivable, Recorded Investment, Aging [Abstract] |  |
Total past due accruing | $ 37 | $ 327

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

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

X
- Definition Financing receivables that are current. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7A -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524 + Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524 + Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentNonaccrualStatus
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Recorded Investment in financing receivables that are past due at the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7A -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524 + Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentPastDue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524 + Details
Name: | us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=nbtb_FinancingReceivables31To60DaysPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=nbtb_FinancingReceivables61To90DaysPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=nbtb_FinancingReceivablesGreaterThan90DaysPastDueMember
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_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
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_OriginatedLoansMember
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_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_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=nbtb_AcquiredLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |