The measurement input for impaired loans.

No definition available.

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

Indicates measurement input for alternative investment.

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 https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 31
-URI https://asc.fasb.org/extlink&oid=123596393&loc=d3e14210-108612

Name:	us-gaap_AlternativeInvestmentMeasurementInputExtensibleList
Namespace Prefix:	us-gaap_
Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	instant

Indicates valuation technique for measuring alternative investment.

Name:	us-gaap_AlternativeInvestmentValuationTechniqueExtensibleList
Namespace Prefix:	us-gaap_
Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	instant

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

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 https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

No definition available.

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

Indicates measurement input for loan held for sale.

Name:	us-gaap_LoansHeldForSaleMeasurementInputExtensibleList
Namespace Prefix:	us-gaap_
Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	instant

Indicates valuation technique for measuring loan held for sale.

Name:	us-gaap_LoansHeldForSaleValuationTechniqueExtensibleList
Namespace Prefix:	us-gaap_
Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	instant

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

Name:	us-gaap_OtherRealEstateOwnedMeasurementInput
Namespace Prefix:	us-gaap_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

Indicates measurement input for real estate owned by financial institution which is not directly related to its business.

Name:	us-gaap_OtherRealEstateOwnedMeasurementInputExtensibleList
Namespace Prefix:	us-gaap_
Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	instant

Indicates valuation technique for measuring real estate owned by financial institution which is not directly related to its business.

Name:	us-gaap_OtherRealEstateOwnedValuationTechniqueExtensibleList
Namespace Prefix:	us-gaap_
Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	instant

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_ValuationTechniqueAxis=qcrh_ValuationTechniqueAppraisalOfCollateralMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputAppraisedValueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FairValueByAssetClassAxis=qcrh_ImpairedLoansLeasesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: