Note 4 - Loans/Leases Receivable - Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) loan	Dec. 31, 2018 USD ($) loan
Number of Loans / Leases \| loan	15	14
Pre-Modification Recorded Investment	$ 1,143	$ 4,123
Post-Modification Recorded Investment	1,093	4,123
Specific Allowance	$ 89	$ 1,810
Payment Deferral [Member]
Number of Loans / Leases \| loan	13	10
Pre-Modification Recorded Investment	$ 500	$ 1,047
Post-Modification Recorded Investment	500	1,047
Specific Allowance	$ 35	$ 310
Payment Deferral [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Number of Loans / Leases \| loan		1
Pre-Modification Recorded Investment		$ 500
Post-Modification Recorded Investment		500
Specific Allowance		$ 60
Extended Maturity [Member]
Number of Loans / Leases \| loan		4
Pre-Modification Recorded Investment		$ 3,076
Post-Modification Recorded Investment		3,076
Specific Allowance		$ 1,500
Extended Maturity [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Number of Loans / Leases \| loan		2
Pre-Modification Recorded Investment		$ 2,976
Post-Modification Recorded Investment		2,976
Specific Allowance		$ 1,492
Principal Forgiveness [Member]
Number of Loans / Leases \| loan	1
Pre-Modification Recorded Investment	$ 587
Post-Modification Recorded Investment	$ 537
Finance Leases Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases \| loan	10	3
Pre-Modification Recorded Investment	$ 388	$ 75
Post-Modification Recorded Investment	388	$ 75
Specific Allowance	$ 35
Commercial Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases \| loan	3	5
Pre-Modification Recorded Investment	$ 112	$ 426
Post-Modification Recorded Investment	$ 112	426
Specific Allowance		$ 250
Residential Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases \| loan		1
Pre-Modification Recorded Investment		$ 46
Post-Modification Recorded Investment		$ 46
Residential Portfolio Segment [Member] \| Extended Maturity [Member]
Number of Loans / Leases \| loan		2
Pre-Modification Recorded Investment		$ 100
Post-Modification Recorded Investment		100
Specific Allowance		$ 8
Consumer Portfolio Segment [Member] \| Extended Maturity [Member]
Number of Loans / Leases \| loan	1
Pre-Modification Recorded Investment	$ 56
Post-Modification Recorded Investment	56
Specific Allowance	$ 54

Specific allowance of amount of investment in financing receivables modified by troubled debt restructurings.

No definition available.

Name:	qcrh_FinancingReceivableModificationsSpecificAllowanceRecordedInvestment
Namespace Prefix:	qcrh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ 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=118936363&loc=SL6953676-111524

+ Details

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- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

+ Details

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

+ Details

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