v3.25.2
Description of Business (Details) - Location
12 Months Ended
May 02, 2025
Dec. 31, 2024
Evans Bancorp, Inc [Member]
Acquisition of Evans Bancorp, Inc [Abstract]
Number of banking locations operated by acquiree
18
18
X
- Definition
Number of banking locations in which the bank operates.
+ References
No definition available.
+ Details
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nbtb_NumberOfBankingLocations
Namespace Prefix:
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Data Type:
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Balance Type:
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Period Type:
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X
- References
No definition available.
+ Details
Name:
us-gaap_BusinessCombinationDescriptionAbstract
Namespace Prefix:
us-gaap_
Data Type:
xbrli:stringItemType
Balance Type:
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Period Type:
duration
X
- Details
Name:
us-gaap_BusinessAcquisitionAxis=nbtb_EvansBancorpIncMember
Namespace Prefix:
Data Type:
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Balance Type:
Period Type: