Note 3 - Loans Leases Receivable - Troubled Debt Restructurings (Details)	3 Months Ended
Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)
Number of Loans / Leases	3	11
Pre-Modification Recorded Investment	$ 93,844	$ 809,813
Post-Modification Recorded Investment	93,844	809,813
Specific Allowance
Payment Deferral [Member]
Number of Loans / Leases		1
Pre-Modification Recorded Investment		$ 6,263
Post-Modification Recorded Investment		6,263
Specific Allowance
Extended Maturity [Member]
Number of Loans / Leases	3	10
Pre-Modification Recorded Investment	$ 93,844	$ 803,550
Post-Modification Recorded Investment	93,844	803,550
Specific Allowance
Commercial Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases		2
Pre-Modification Recorded Investment		$ 133,689
Post-Modification Recorded Investment		133,689
Specific Allowance
Residential Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases	1
Pre-Modification Recorded Investment	$ 46,320
Post-Modification Recorded Investment	46,320
Specific Allowance
Finance Leases Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases		1
Pre-Modification Recorded Investment		$ 6,263
Post-Modification Recorded Investment		6,263
Specific Allowance
Finance Leases Portfolio Segment [Member] \| Extended Maturity [Member]
Number of Loans / Leases	2	8
Pre-Modification Recorded Investment	$ 47,524	$ 669,861
Post-Modification Recorded Investment	47,524	669,861
Specific Allowance

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

No definition available.

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Namespace Prefix:	qcrh_
Data Type:	xbrli:monetaryItemType
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

+ Details

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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

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