NOTE 4 - DERIVATIVES AND HEDGING ACTIVITIES - Summary of Interest Rate Swaps Derivatives (Details) - Designated as Hedging Instrument [Member] - Cash Flow Hedging [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Other Assets | Derivative Instrument One Maturing 2023 [Member]
Notional Amount	$ 25,000
Fair Value - Asset	$ 18	$ 112
Other Assets | Derivative Instrument One Maturing 2023 [Member] | London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.75%
Other Assets | Derivative Instrument Two Maturing 2023 [Member]
Notional Amount	$ 50,000
Fair Value - Asset	$ 35	218
Other Assets | Derivative Instrument Two Maturing 2023 [Member] | London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.57%
Other Assets | Derivative Instrument Three Maturing 2023 [Member]
Notional Amount	$ 25,000
Fair Value - Asset	$ 16	96
Other Assets | Derivative Instrument Three Maturing 2023 [Member] | London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.90%
Other Assets | Derivative Instrument Four Maturing 2023 [Member]
Notional Amount	$ 25,000
Fair Value - Asset	$ 17	109
Other Assets | Derivative Instrument Four Maturing 2023 [Member] | London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.80%
Other Assets | Derivative Instrument One Maturing 2024 [Member]
Notional Amount	$ 25,000
Fair Value - Asset	$ 47	214
Other Assets | Derivative Instrument One Maturing 2024 [Member] | London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.75%
Other Assets | Derivative Instrument Two Maturing 2024 [Member]
Notional Amount	$ 50,000
Fair Value - Asset	$ 85	401
Other Assets | Derivative Instrument Two Maturing 2024 [Member] | London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.57%
Other Assets | Derivative Instrument Three Maturing 2024 [Member]
Notional Amount	$ 25,000
Fair Value - Asset	$ 44	202
Other Assets | Derivative Instrument Three Maturing 2024 [Member] | London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.90%
Other Assets | Derivative Instrument Four Maturing 2024 [Member]
Notional Amount	$ 25,000
Fair Value - Asset	$ 42	201
Other Assets | Derivative Instrument Four Maturing 2024 [Member] | London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.80%
Other Assets | Derivative Instrument One Maturing 2025 [Member]
Notional Amount	$ 25,000
Fair Value - Asset	$ 94	337
Other Assets | Derivative Instrument One Maturing 2025 [Member] | London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.75%
Other Assets | Derivative Instrument Two Maturing 2025 [Member]
Notional Amount	$ 50,000
Fair Value - Asset	$ 171	617
Other Assets | Derivative Instrument Two Maturing 2025 [Member] | London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.57%
Other Assets | Derivative Instrument Three Maturing 2025 [Member]
Notional Amount	$ 25,000
Fair Value - Asset	$ 94	332
Other Assets | Derivative Instrument Three Maturing 2025 [Member] | London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.90%
Other Assets | Derivative Instrument Four Maturing 2025 [Member]
Notional Amount	$ 25,000
Fair Value - Asset	$ 86	309
Other Assets | Derivative Instrument Four Maturing 2025 [Member] | London Interbank Offered Rate (LIBOR)
Derivative, Basis Spread on Variable Rate	1.80%
Other Assets | Interest rate swap
Notional Amount	$ 375,000
Fair Value - Asset	749	3,148
Derivative Liabilities | Interest rate swap
Notional Amount	79,000
Fair Value - Liability	$ (8,520)	(3,758)
Receive Rate	3.66%
Pay Rate	5.24%
Derivative Liabilities | CRBT - FHLB Advances or Brokered CDs [Member]
Notional Amount	$ 30,000
Fair Value - Liability	$ (644)
Receive Rate	0.89%
Pay Rate	1.12%
Derivative Liabilities | SFCB - FHLB Advances or Brokered CDs [Member]
Notional Amount	$ 10,000
Fair Value - Liability	$ (162)
Receive Rate	0.74%
Pay Rate	0.95%
Derivative Liabilities | QCR Holdings Statutory Trust II
Notional Amount	$ 10,000
Fair Value - Liability	$ (1,992)	(971)
Receive Rate	4.30%
Pay Rate	5.85%
Derivative Liabilities | QCR Holdings Statutory Trust III
Notional Amount	$ 8,000
Fair Value - Liability	$ (1,594)	(777)
Receive Rate	4.30%
Pay Rate	5.85%
Derivative Liabilities | QCR Holdings Statutory Trust V
Notional Amount	$ 10,000
Fair Value - Liability	$ (1,935)	(944)
Receive Rate	3.54%
Pay Rate	4.54%
Derivative Liabilities | Community National Statutory Trust II
Notional Amount	$ 3,000
Fair Value - Liability	$ (597)	(291)
Receive Rate	3.29%
Pay Rate	5.17%
Derivative Liabilities | Community National Statutory Trust III
Notional Amount	$ 3,500
Fair Value - Liability	$ (698)	(339)
Receive Rate	2.49%
Pay Rate	4.75%
Derivative Liabilities | Guaranty Bankshares Statutory Trust I
Notional Amount	$ 4,500
Fair Value - Liability	$ (898)	$ (436)
Receive Rate	2.49%
Pay Rate	4.75%