Note 22 - Fair Value - Quantitative Information About Level Fair Value Measurements (Details) $ in Thousands	Dec. 31, 2019 USD ($) item	Dec. 31, 2018 USD ($)
Fair value	$ 7,853	$ 19,785
Amount of fair value assets transferred from Level 1 to Level 2	0	0
Amount of fair value assets transferred from Level 2 to Level 1	0	0
Amount of fair value liabilities transferred from Level 1 to Level 2	0	0
Amount of fair value liabilities transferred from Level 2 to Level 1	0	0
Impaired Loans Leases [Member]
Fair value	$ 3,394	9,657
Valuation technique	qcrh:ValuationTechniqueAppraisalOfCollateralMember
Unobservable input	us-gaap:MeasurementInputAppraisedValueMember
Impaired Loans Leases [Member] \| Minimum
Impaired loans/leases, measurement input \| item	(10.00)
Impaired Loans Leases [Member] \| Maximum
Impaired loans/leases, measurement input \| item	(30.00)
Other Securities
Fair value	$ 4,459	10,128
Valuation technique	qcrh:ValuationTechniqueAppraisalOfCollateralMember
Unobservable input	us-gaap:MeasurementInputAppraisedValueMember
Other Securities \| Minimum
OREO, measurement input \| item	0.00
Other Securities \| Maximum
OREO, measurement input \| item	(35.00)
Other Real Estate Owned [Member]
Fair value	$ 4,459	10,128
Fair Value, Inputs, Level 3 [Member]
Fair value	7,853	19,785
Fair Value, Inputs, Level 3 [Member] \| Impaired Loans Leases [Member]
Fair value	3,394	9,657
Fair Value, Inputs, Level 3 [Member] \| Other Real Estate Owned [Member]
Fair value	$ 4,459	$ 10,128

The measurement input for impaired loans.

No definition available.

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Namespace Prefix:	qcrh_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

Indicates measurement input for alternative investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14210-108612

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- Definition

Indicates valuation technique for measuring alternative investment.

+ References

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Period Type:	instant

- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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

- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Period Type:	instant

- Definition

Value of input used to measure real estate owned by financial institution by financial institution which is not directly related to its business.

+ References

+ Details

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Period Type:	instant

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