Note 4 - Loans/Leases Receivable - Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($) loan
Number of Loans / Leases	4	15
Pre-Modification Recorded Investment	$ 1,022	$ 1,143
Post-Modification Recorded Investment	$ 1,022	1,093
Specific Allowance		$ 89
Payment Deferral [Member]
Number of Loans / Leases \| loan	3	13
Pre-Modification Recorded Investment	$ 187	$ 500
Post-Modification Recorded Investment	$ 187	500
Specific Allowance		$ 35
Direct financing leases \| Payment Deferral [Member]
Number of Loans / Leases \| loan	2	10
Pre-Modification Recorded Investment	$ 112	$ 388
Post-Modification Recorded Investment	$ 112	388
Specific Allowance		$ 35
Commercial Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases \| loan	1	3
Pre-Modification Recorded Investment	$ 75	$ 112
Post-Modification Recorded Investment	$ 75	$ 112
Commercial Portfolio Segment [Member] \| Principal Forgiveness [Member]
Number of Loans / Leases \| loan		1
Pre-Modification Recorded Investment		$ 587
Post-Modification Recorded Investment		$ 537
Consumer Portfolio Segment [Member] \| Extended Maturity [Member]
Number of Loans / Leases \| loan	1
Pre-Modification Recorded Investment	$ 835
Post-Modification Recorded Investment	$ 835
Installment And Other Consumer [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.

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Namespace Prefix:	qcrh_
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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=121611835&loc=SL6953676-111524

+ Details

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- Definition

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

+ References

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- Definition

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

+ References

+ Details

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