Note 4 - Loans Leases Receivable - Troubled Debt Restructurings (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2018 USD ($) loan item	Sep. 30, 2017 USD ($) item	Sep. 30, 2018 USD ($) lease loan	Sep. 30, 2017 USD ($) lease
Number of loans restructured \| loan	0		0
Number of Loans / Leases	8	8	11	36
Pre-Modification Recorded Investment	$ 4,309,980	$ 1,037,049	$ 4,403,824	$ 2,795,032
Post-Modification Recorded Investment	4,309,980	$ 1,037,049	4,403,824	$ 2,795,032
Specific Allowance	$ 1,149,420		$ 1,149,420
Extended Maturity [Member]
Number of Loans / Leases	3		3	2
Pre-Modification Recorded Investment	$ 3,010,990		$ 3,010,990	$ 104,382
Post-Modification Recorded Investment	3,010,990		3,010,990	$ 104,382
Specific Allowance	$ 815,703		$ 815,703
Extended Maturity [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Number of Loans / Leases	2		2
Pre-Modification Recorded Investment	$ 2,975,703		$ 2,975,703
Post-Modification Recorded Investment	2,975,703		2,975,703
Specific Allowance	$ 815,703		$ 815,703
Payment Deferral [Member]
Number of Loans / Leases	5	8	8	34
Pre-Modification Recorded Investment	$ 1,298,990	$ 1,037,049	$ 1,392,834	$ 2,690,650
Post-Modification Recorded Investment	1,298,990	$ 1,037,049	1,392,834	$ 2,690,650
Specific Allowance	$ 333,717		$ 333,717
Payment Deferral [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Number of Loans / Leases	2		2
Pre-Modification Recorded Investment	$ 980,899		$ 980,899
Post-Modification Recorded Investment	980,899		980,899
Specific Allowance	$ 60,000		$ 60,000
Finance Leases Portfolio Segment [Member] \| Extended Maturity [Member]
Number of Loans / Leases \| lease				2
Pre-Modification Recorded Investment				$ 104,382
Post-Modification Recorded Investment				$ 104,382
Finance Leases Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases	2	4	4	27
Pre-Modification Recorded Investment	$ 44,374	$ 416,597	$ 91,898	$ 1,889,000
Post-Modification Recorded Investment	$ 44,374	$ 416,597	$ 91,898	$ 1,889,000
Commercial Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases	1	4	1	7
Pre-Modification Recorded Investment	$ 273,717	$ 620,452	$ 273,717	$ 801,650
Post-Modification Recorded Investment	273,717	$ 620,452	273,717	$ 801,650
Specific Allowance	$ 273,717		$ 273,717
Residential Portfolio Segment [Member] \| Extended Maturity [Member]
Number of Loans / Leases	1		1
Pre-Modification Recorded Investment	$ 35,287		$ 35,287
Post-Modification Recorded Investment	$ 35,287		$ 35,287
Residential Portfolio Segment [Member] \| Payment Deferral [Member]
Number of Loans / Leases \| lease			1
Pre-Modification Recorded Investment			$ 46,320
Post-Modification Recorded Investment			$ 46,320

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Namespace Prefix:	qcrh_
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Balance Type:	credit
Period Type:	duration

- Definition

The number of loans restructured during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	qcrh_
Data Type:	xbrli:integerItemType
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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

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- Definition

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- Definition

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

+ References

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