Note 12 - Junior Subordinated Debentures - Trust Preferred Securities (Details) - USD ($)		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015
Amount Outstanding		$ 35,570,000	$ 40,725,000
Interest Rate		3.26%	2.60%
Trust Preferred Securities [Member]
Date issued	[1]	February 2004
Trust Preferred Securities [Member] | QCR Holdings Statuory Trust II [Member]
Amount Outstanding	[1]	$ 10,310,000	$ 10,310,000
Interest Rate, Basis Spread	[1]	2.85%
Interest Rate	[1]	3.85%	3.18%
Trust Preferred Securities [Member] | QCR Holdings Statutory Trust III [Member]
Date issued		February 2004
Amount Outstanding		$ 8,248,000	$ 8,248,000
Interest Rate, Basis Spread		2.85%
Interest Rate		3.85%	3.18%
Trust Preferred Securities [Member] | QCR Holdings Statutory Trust IV [Member]
Date issued		May 2005
Amount Outstanding			$ 5,155,000
Interest Rate, Basis Spread		1.80%
Interest Rate			2.12%
Trust Preferred Securities [Member] | QCR Holdings Statutory Trust V [Member]
Date issued		February 2006
Amount Outstanding		$ 10,310,000	$ 10,310,000
Interest Rate, Basis Spread		1.55%
Interest Rate		2.43%	1.87%
Trust Preferred Securities [Member] | Community National Statutory Trust II [Member]
Date issued		September 2004
Amount Outstanding		$ 3,093,000	$ 3,093,000
Interest Rate, Basis Spread		2.17%
Interest Rate		3.17%	2.74%
Trust Preferred Securities [Member] | Community National Statutory Trust III [Member]
Date issued		March 2007
Amount Outstanding		$ 3,609,000	$ 3,609,000
Interest Rate, Basis Spread		1.75%
Interest Rate		2.71%	2.26%

[1] Original amount issued for QCR Holdings Statutory Trust II was $12,372,000.