Note 8 - Specific Reserve for Loans Modified as TDR's (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Receivables [Abstract]
TDRs with no specific allowance recorded - unpaid principal balance	$ 2,208	$ 2,957
TDRs with an allowance recorded - unpaid principal balance	3,356	2,934
Unpaid principal balance	5,564	5,891
TDRs with an allowance recorded - related allowance	$ 543	$ 450

Financing allowance for credit losses change in method of calculating impairment.

No definition available.

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Period Type:	instant

- Definition

Financing receivables change in method of calculating impairment recorded investment.

+ References

No definition available.

+ Details

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- Definition

Amount of investment in loans modified under a troubled debt restructuring for which there is a related allowance for credit losses.

+ References

No definition available.

+ Details

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Namespace Prefix:	qnbc_
Data Type:	xbrli:monetaryItemType
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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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- References

No definition available.

+ Details

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