NOTE 4 - DERIVATIVES AND HEDGING ACTIVITIES - Summary of Interest Rate Cap Derivatives (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2021	Dec. 31, 2020
Derivative Assets	$ 193,395	$ 222,757
Interest rate swap
Derivative Assets	191,134	222,431
Interest rate cap
Derivative Assets	158	67
Cash Flow Hedging \| Interest rate swap
Derivative Assets	1,490
Cash Flow Hedging \| Interest rate cap
Derivative Assets	613	259
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging
Notional Amount	150,000
Fair Value - Asset	1,490
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument One Maturing 2023 [Member]
Notional Amount	25,000
Fair Value - Asset	$ 3	3
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument One Maturing 2023 [Member] \| London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.75%
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument Two Maturing 2023 [Member]
Notional Amount	$ 50,000
Fair Value - Asset	$ 8	5
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument Two Maturing 2023 [Member] \| London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.57%
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument Three Maturing 2023 [Member]
Notional Amount	$ 25,000
Fair Value - Asset	$ 3	3
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument Three Maturing 2023 [Member] \| London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.80%
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument One Maturing 2024 [Member]
Notional Amount	$ 25,000
Fair Value - Asset	$ 35	15
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument One Maturing 2024 [Member] \| London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.75%
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument Two Maturing 2024 [Member]
Notional Amount	$ 50,000
Fair Value - Asset	$ 73	31
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument Two Maturing 2024 [Member] \| London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.57%
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument Three Maturing 2024 [Member]
Notional Amount	$ 25,000
Fair Value - Asset	$ 37	15
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument Three Maturing 2024 [Member] \| London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.80%
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument One Maturing 2025 [Member]
Notional Amount	$ 25,000
Fair Value - Asset	$ 110	46
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument One Maturing 2025 [Member] \| London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.75%
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument Two Maturing 2025 [Member]
Notional Amount	$ 50,000
Fair Value - Asset	$ 229	94
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument Two Maturing 2025 [Member] \| London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.57%
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument Four Maturing 2025 [Member]
Notional Amount	$ 25,000
Fair Value - Asset	$ 115	47
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Derivative Instrument Four Maturing 2025 [Member] \| London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.80%
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| QCBT - Loans
Notional Amount	$ 35,000
Fair Value - Asset	$ 351
Receive Rate	1.40%
Pay Rate	2.81%
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| CRBT - Loans
Notional Amount	$ 50,000
Fair Value - Asset	$ 502
Receive Rate	1.40%
Pay Rate	2.81%
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| CSB - Loans
Notional Amount	$ 40,000
Fair Value - Asset	$ 386
Receive Rate	1.40%
Pay Rate	2.81%
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| SFCB - Loans
Notional Amount	$ 25,000
Fair Value - Asset	$ 251
Receive Rate	1.40%
Pay Rate	2.81%
Designated as Hedging Instrument \| Derivative Assets \| Cash Flow Hedging \| Interest rate cap
Notional Amount	$ 300,000
Fair Value - Asset	613	259
Designated as Hedging Instrument \| Derivative Liabilities \| Cash Flow Hedging \| Interest rate swap
Notional Amount	39,000
Fair Value - Liability	(4,958)	(6,839)
Designated as Hedging Instrument \| Derivative Liabilities \| Cash Flow Hedging \| QCR Holdings Statutory Trust II
Notional Amount	10,000
Fair Value - Liability	$ (1,282)	(1,767)
Receive Rate	3.00%
Pay Rate	5.85%
Designated as Hedging Instrument \| Derivative Liabilities \| Cash Flow Hedging \| QCR Holdings Statutory Trust III
Notional Amount	$ 8,000
Fair Value - Liability	$ (1,025)	(1,414)
Receive Rate	3.00%
Pay Rate	5.85%
Designated as Hedging Instrument \| Derivative Liabilities \| Cash Flow Hedging \| QCR Holdings Statutory Trust V
Notional Amount	$ 10,000
Fair Value - Liability	$ (1,246)	(1,721)
Receive Rate	1.74%
Pay Rate	4.54%
Designated as Hedging Instrument \| Derivative Liabilities \| Cash Flow Hedging \| Community National Statutory Trust II
Notional Amount	$ 3,000
Fair Value - Liability	$ (383)	(529)
Receive Rate	2.30%
Pay Rate	5.17%
Designated as Hedging Instrument \| Derivative Liabilities \| Cash Flow Hedging \| Community National Statutory Trust III
Notional Amount	$ 3,500
Fair Value - Liability	$ (447)	(616)
Receive Rate	1.87%
Pay Rate	4.75%
Designated as Hedging Instrument \| Derivative Liabilities \| Cash Flow Hedging \| Guaranty Bankshares Statutory Trust I
Notional Amount	$ 4,500
Fair Value - Liability	$ (575)	(792)
Receive Rate	1.87%
Pay Rate	4.75%
Not Designated as Hedging Instrument \| Interest rate swap
Derivative Assets	$ 191,134	222,431
Not Designated as Hedging Instrument \| Derivative Assets
Notional Amount	75,000
Derivative Assets	158	67
Not Designated as Hedging Instrument \| Derivative Assets \| Derivative Instrument One Maturing 2023 [Member]
Notional Amount	25,000
Derivative Assets	$ 3	2
Not Designated as Hedging Instrument \| Derivative Assets \| Derivative Instrument One Maturing 2023 [Member] \| London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.90%
Not Designated as Hedging Instrument \| Derivative Assets \| Derivative Instrument One Maturing 2024 [Member]
Notional Amount	$ 25,000
Derivative Assets	$ 35	15
Not Designated as Hedging Instrument \| Derivative Assets \| Derivative Instrument One Maturing 2024 [Member] \| London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.90%
Not Designated as Hedging Instrument \| Derivative Assets \| Derivative Instrument One Maturing 2025 [Member]
Notional Amount	$ 25,000
Derivative Assets	$ 120	$ 50
Not Designated as Hedging Instrument \| Derivative Assets \| Derivative Instrument One Maturing 2025 [Member] \| London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.90%

Represents the pay rate of the derivative instrument.

No definition available.

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- Definition

Represents the receive rate of the derivative instrument.

+ References

No definition available.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

The percentage points added to the reference rate to compute the variable rate on the interest rate derivative.

+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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- Definition

Fair value as of the balance sheet date of all interest rate derivative assets designated as cash flow hedging instruments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

+ References

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