Note 8 - Specific Reserve for Loans Modified as TDR's (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Receivables [Abstract]
TDRs with no specific allowance recorded - unpaid principal balance	$ 3,398	$ 3,448
TDRs with an allowance recorded - unpaid principal balance	279	867
Unpaid principal balance	3,677	4,315
TDRs with an allowance recorded - related allowance	$ 190	$ 235

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

No definition available.

+ Details

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Namespace Prefix:	qnbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of allowance for credit losses related to receivables which had been measured under a general allowance for credit losses methodology that are now identified as troubled debt restructurings.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of the outstanding recorded investment related to 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 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

+ Details

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- References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of receivables for which the allowance for credit losses had previously been measured under a general allowance for credit losses methodology, and are now identified as troubled debt restructurings.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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