Note 9 - Earnings Per Share (Details) - Earnings Per Share - Basic and Diluted - USD ($)		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share, Basic and Diluted [Abstract]
Net income (in Dollars)		$ 6,488,987	$ 4,062,665	$ 10,143,058	$ 11,959,716
Less: Preferred stock dividends (in Dollars)					1,081,877
Net income attributable to QCR Holdings, Inc. common stockholders (in Dollars)		$ 6,488,987	$ 4,062,665	$ 10,143,058	$ 10,877,839
Earnings per common share attributable to QCR Holdings, Inc. common stockholders
Basic (in Dollars per share)		$ 0.55	$ 0.51	$ 1.03	$ 1.37
Diluted (in Dollars per share)		$ 0.55	$ 0.50	$ 1.01	$ 1.35
Weighted average common shares outstanding*	[1]	11,713,993	7,931,944	9,878,882	7,919,201
Weighted average common shares issuable upon exercise of stock options and under the employee stock purchase plan		161,937	122,041	145,559	121,217
Weighted average common and common equivalent shares outstanding		11,875,930	8,053,985	10,024,441	8,040,418

[1] The increase in weighted average common shares outstanding was primarily due to the common stock issuance discussed in Note 7 to the Consolidated Financial Statements.