The amount of gain (loss) on loans and leases receivable.

No definition available.

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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

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- Definition

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

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

The amount of the outstanding recorded investment related to 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 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

+ Details

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

- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

+ Details

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

- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

+ Details

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

- Definition

Amount, after allowance for bad debt, of mortgage loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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- Details

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- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LoanRestructuringModificationAxis=qcrh_TroubledDebtRestructuringsMember
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Data Type:	na
Balance Type:
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- Details

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- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
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- Details

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- Details

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- Details

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Note 3 - Loans Leases Receivable - Textual (Details)	3 Months Ended			6 Months Ended		12 Months Ended
Note 3 - Loans Leases Receivable - Textual (Details)	Jun. 30, 2018 USD ($) item	Dec. 31, 2017 USD ($)	Jun. 30, 2017 USD ($) item	Jun. 30, 2018 USD ($) lease item	Jun. 30, 2017 USD ($) lease item	Dec. 31, 2017 USD ($)
Loans and leases	$ 3,105,901,458	$ 2,956,713,493		$ 3,105,901,458		$ 2,956,713,493
Loans and leases receivable loss	0		$ 0	0	$ 0
Financing Receivable, Recorded Investment, Nonaccrual Status	12,553,800	11,441,234		12,553,800		11,441,234
Financing Receivable, Modifications, Recorded Investment	$ 3,168,014	9,394,967		$ 3,168,014		9,394,967
Financing Receivable, Modifications, Number of Contracts			17	3	28
Financing Receivable, Modifications, Post-Modification Recorded Investment			$ 948,170	$ 93,844	$ 1,757,983
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| item	7		2	7	2
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down		195,000		$ 577,377		65,623
One Customer [Member]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment				78,000
Other Customers [Member]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment				$ 378,000
Nonaccrual [Member]
Financing Receivable, Modifications, Number of Contracts \| item				1
Financing Receivable, Modifications, Post-Modification Recorded Investment				$ 46,320	$ 0
Troubled Debt Restructurings [Member]
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 1,841,006	2,282,495		1,841,006		2,282,495
Residential Portfolio Segment [Member]
Loans and leases	257,433,713	258,646,265		257,433,713		258,646,265
Loans Receivable Held-for-sale, Net, Not Part of Disposal Group, Mortgage	1,033,700	645,001		1,033,700		645,001
Financing Receivable, Recorded Investment, Nonaccrual Status	1,315,151	1,363,806		1,315,151		1,363,806
Residential Portfolio Segment [Member] \| Troubled Debt Restructurings [Member]
Financing Receivable, Recorded Investment, Nonaccrual Status	83,287	115,190		83,287		115,190
Commercial Portfolio Segment [Member]
Loans and leases	1,273,000,094	1,134,516,315		1,273,000,094		1,134,516,315
Financing Receivable, Recorded Investment, Nonaccrual Status	1,485,295	1,231,353		1,485,295		1,231,353
Commercial Portfolio Segment [Member] \| Troubled Debt Restructurings [Member]
Financing Receivable, Recorded Investment, Nonaccrual Status	66,021	122,598		66,021		122,598
Commercial Portfolio Segment [Member] \| m2 Lease Funds, LLC [Member]
Loans and leases	92,815,742	66,758,397		92,815,742		66,758,397
Commercial Real Estate Portfolio Segment [Member]
Loans and leases	1,349,318,914	1,303,491,882		1,349,318,914		1,303,491,882
Commercial Real Estate Portfolio Segment [Member] \| Troubled Debt Restructurings [Member]
Financing Receivable, Recorded Investment, Nonaccrual Status	1,066,701	1,336,871		1,066,701		1,336,871
Finance Leases Portfolio Segment [Member]
Loans and leases	133,196,613	141,448,232		133,196,613		141,448,232
Financing Receivable, Recorded Investment, Nonaccrual Status	2,529,004	2,175,044		2,529,004		2,175,044
Finance Leases Portfolio Segment [Member] \| Troubled Debt Restructurings [Member]
Financing Receivable, Recorded Investment, Nonaccrual Status	619,727	700,255		619,727		700,255
Consumer Portfolio Segment [Member]
Loans and leases	92,952,124	118,610,799		92,952,124		118,610,799
Financing Receivable, Recorded Investment, Nonaccrual Status	202,390	249,091		202,390		249,091
Consumer Portfolio Segment [Member] \| Troubled Debt Restructurings [Member]
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 5,270	$ 7,581		$ 5,270		$ 7,581