Note 8 - Regulatory Capital Requirements and Restrictions On Dividends (Details) - Capital Requirements - USD ($) $ in Thousands		Jun. 30, 2015	Dec. 31, 2014
Parent Company [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total risk-based capital actual amount		$ 267,743	$ 204,376
Total risk-based capital actual ratio		12.92%	10.91%
Total risk-based capital for capital adequacy purposes amount		$ 165,750	$ 149,876
Total risk-based capital for capital adequacy purposes ratio		8.00%	8.00%
Total risk-based capital to be well capitalized under prompt corrective action provisions amount		$ 207,188
Total risk-based capital to be well capitalized under prompt corrective action provisions ratio		10.00%
Total risk-based capital new Basel III minimums amount	[1]	$ 165,750
Total risk-based capital new Basel III minimums ratio	[1]	8.00%
Tier 1 risk-based capital actual amount		$ 241,548	$ 178,364
Tier 1 risk-based capital actual ratio		11.66%	9.52%
Tier 1 risk-based capital for capital adequacy purposes amount		$ 124,313	$ 74,938
Tier 1 risk-based capital for capital adequacy purposes ratio		6.00%	4.00%
Tier 1 risk-based capital to be well capitalized under prompt corrective action provisions amount		$ 165,750
Tier 1 risk-based capital to be well capitalized under prompt corrective action provisions ratio		8.00%
Tier 1 risk-based capital new Basel III minimums amount	[1]	$ 124,313
Tier 1 risk-based capital new Basel III minimums ratio	[1]	6.00%
Tier 1 leverage actual amount		$ 241,548	$ 178,364
Tier 1 leverage actual ratio		9.62%	7.62%
Tier 1 leverage for capital adequacy purposes amount		$ 100,436	$ 93,658
Tier 1 leverage for capital adequacy purposes ratio		4.00%	4.00%
Tier 1 leverage to be well capitalized under prompt corrective action provisions amount		$ 125,545
Tier 1 leverage to be well capitalized under prompt corrective action provisions ratio		5.00%
Tier 1 leverage new Basel III minimums amount	[1]	$ 100,436
Tier 1 leverage new Basel III minimums ratio	[1]	4.00%
Common equity Tier 1 actual amount		$ 241,548
Common equity Tier 1 actual ratio		9.97%
Common equity Tier 1 capital adequacy purposes amount		$ 93,234
Common equity Tier 1 capital adequacy purposes ratio		4.50%
Common equity Tier 1 to be well capitalized under prompt corrective action provisions amount		$ 134,672
Common equity Tier 1 to be well capitalized under prompt corrective action provisions ratio		6.50%
Common equity Tier 1 new Basel III minimums amount	[1]	$ 93,234
Common equity Tier 1 new Basel III minimums ratio	[1]	4.50%
Quad City Bank and Trust Company [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total risk-based capital actual amount		$ 130,828	$ 104,869
Total risk-based capital actual ratio		12.91%	11.26%
Total risk-based capital for capital adequacy purposes amount		$ 81,107	$ 74,495
Total risk-based capital for capital adequacy purposes ratio		8.00%	8.00%
Total risk-based capital to be well capitalized under prompt corrective action provisions amount		$ 101,384	$ 93,119
Total risk-based capital to be well capitalized under prompt corrective action provisions ratio		10.00%	10.00%
Total risk-based capital new Basel III minimums amount	[1]	$ 81,107
Total risk-based capital new Basel III minimums ratio	[1]	8.00%
Tier 1 risk-based capital actual amount		$ 118,182	$ 93,785
Tier 1 risk-based capital actual ratio		11.66%	10.07%
Tier 1 risk-based capital for capital adequacy purposes amount		$ 60,830	$ 37,248
Tier 1 risk-based capital for capital adequacy purposes ratio		6.00%	4.00%
Tier 1 risk-based capital to be well capitalized under prompt corrective action provisions amount		$ 81,107	$ 55,872
Tier 1 risk-based capital to be well capitalized under prompt corrective action provisions ratio		8.00%	6.00%
Tier 1 risk-based capital new Basel III minimums amount	[1]	$ 60,830
Tier 1 risk-based capital new Basel III minimums ratio	[1]	6.00%
Tier 1 leverage actual amount		$ 118,182	$ 93,785
Tier 1 leverage actual ratio		8.86%	7.10%
Tier 1 leverage for capital adequacy purposes amount		$ 53,347	$ 52,817
Tier 1 leverage for capital adequacy purposes ratio		4.00%	4.00%
Tier 1 leverage to be well capitalized under prompt corrective action provisions amount		$ 66,683	$ 66,021
Tier 1 leverage to be well capitalized under prompt corrective action provisions ratio		5.00%	5.00%
Tier 1 leverage new Basel III minimums amount	[1]	$ 53,347
Tier 1 leverage new Basel III minimums ratio	[1]	4.00%
Common equity Tier 1 actual amount		$ 118,182
Common equity Tier 1 actual ratio		11.66%
Common equity Tier 1 capital adequacy purposes amount		$ 45,623
Common equity Tier 1 capital adequacy purposes ratio		4.50%
Common equity Tier 1 to be well capitalized under prompt corrective action provisions amount		$ 65,900
Common equity Tier 1 to be well capitalized under prompt corrective action provisions ratio		6.50%
Common equity Tier 1 new Basel III minimums amount	[1]	$ 45,623
Common equity Tier 1 new Basel III minimums ratio	[1]	4.50%
Cedar Rapids Bank and Trust [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total risk-based capital actual amount		$ 101,472	$ 76,662
Total risk-based capital actual ratio		13.73%	11.54%
Total risk-based capital for capital adequacy purposes amount		$ 59,112	$ 53,126
Total risk-based capital for capital adequacy purposes ratio		8.00%	8.00%
Total risk-based capital to be well capitalized under prompt corrective action provisions amount		$ 73,889	$ 66,407
Total risk-based capital to be well capitalized under prompt corrective action provisions ratio		10.00%	10.00%
Total risk-based capital new Basel III minimums amount	[1]	$ 59,112
Total risk-based capital new Basel III minimums ratio	[1]	8.00%
Tier 1 risk-based capital actual amount		$ 92,223	$ 68,772
Tier 1 risk-based capital actual ratio		12.48%	10.36%
Tier 1 risk-based capital for capital adequacy purposes amount		$ 44,334	$ 26,563
Tier 1 risk-based capital for capital adequacy purposes ratio		6.00%	4.00%
Tier 1 risk-based capital to be well capitalized under prompt corrective action provisions amount		$ 59,112	$ 39,844
Tier 1 risk-based capital to be well capitalized under prompt corrective action provisions ratio		8.00%	6.00%
Tier 1 risk-based capital new Basel III minimums amount	[1]	$ 44,334
Tier 1 risk-based capital new Basel III minimums ratio	[1]	6.00%
Tier 1 leverage actual amount		$ 92,223	$ 68,772
Tier 1 leverage actual ratio		10.73%	8.21%
Tier 1 leverage for capital adequacy purposes amount		$ 34,387	$ 33,525
Tier 1 leverage for capital adequacy purposes ratio		4.00%	4.00%
Tier 1 leverage to be well capitalized under prompt corrective action provisions amount		$ 42,984	$ 41,906
Tier 1 leverage to be well capitalized under prompt corrective action provisions ratio		5.00%	5.00%
Tier 1 leverage new Basel III minimums amount	[1]	$ 34,387
Tier 1 leverage new Basel III minimums ratio	[1]	4.00%
Common equity Tier 1 actual amount		$ 92,223
Common equity Tier 1 actual ratio		12.48%
Common equity Tier 1 capital adequacy purposes amount		$ 33,250
Common equity Tier 1 capital adequacy purposes ratio		4.50%
Common equity Tier 1 to be well capitalized under prompt corrective action provisions amount		$ 48,028
Common equity Tier 1 to be well capitalized under prompt corrective action provisions ratio		6.50%
Common equity Tier 1 new Basel III minimums amount	[1]	$ 33,250
Common equity Tier 1 new Basel III minimums ratio	[1]	4.50%
Rockford Bank and Trust [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total risk-based capital actual amount		$ 37,885	$ 35,906
Total risk-based capital actual ratio		11.71%	12.56%
Total risk-based capital for capital adequacy purposes amount		$ 25,891	$ 22,875
Total risk-based capital for capital adequacy purposes ratio		8.00%	8.00%
Total risk-based capital to be well capitalized under prompt corrective action provisions amount		$ 32,363	$ 28,594
Total risk-based capital to be well capitalized under prompt corrective action provisions ratio		10.00%	10.00%
Total risk-based capital new Basel III minimums amount	[1]	$ 25,891
Total risk-based capital new Basel III minimums ratio	[1]	8.00%
Tier 1 risk-based capital actual amount		$ 33,838	$ 32,325
Tier 1 risk-based capital actual ratio		10.46%	11.30%
Tier 1 risk-based capital for capital adequacy purposes amount		$ 19,418	$ 11,438
Tier 1 risk-based capital for capital adequacy purposes ratio		6.00%	4.00%
Tier 1 risk-based capital to be well capitalized under prompt corrective action provisions amount		$ 25,891	$ 17,156
Tier 1 risk-based capital to be well capitalized under prompt corrective action provisions ratio		8.00%	6.00%
Tier 1 risk-based capital new Basel III minimums amount	[1]	$ 19,418
Tier 1 risk-based capital new Basel III minimums ratio	[1]	6.00%
Tier 1 leverage actual amount		$ 33,838	$ 32,325
Tier 1 leverage actual ratio		9.42%	9.16%
Tier 1 leverage for capital adequacy purposes amount		$ 14,369	$ 14,112
Tier 1 leverage for capital adequacy purposes ratio		4.00%	4.00%
Tier 1 leverage to be well capitalized under prompt corrective action provisions amount		$ 17,961	$ 17,640
Tier 1 leverage to be well capitalized under prompt corrective action provisions ratio		5.00%	5.00%
Tier 1 leverage new Basel III minimums amount	[1]	$ 14,369
Tier 1 leverage new Basel III minimums ratio	[1]	4.00%
Common equity Tier 1 actual amount		$ 33,838
Common equity Tier 1 actual ratio		10.46%
Common equity Tier 1 capital adequacy purposes amount		$ 14,564
Common equity Tier 1 capital adequacy purposes ratio		4.50%
Common equity Tier 1 to be well capitalized under prompt corrective action provisions amount		$ 21,036
Common equity Tier 1 to be well capitalized under prompt corrective action provisions ratio		6.50%
Common equity Tier 1 new Basel III minimums amount	[1]	$ 14,564
Common equity Tier 1 new Basel III minimums ratio	[1]	4.50%

[1] The minimums under Basel III phase-in higher by .625% (the capital conservation buffer) annually until 2019. The fully phased-in mimimums are 10.5% (Total risk-based capital), 8.5% (Tier 1 risk-based capital), and 7.0% (Common equity Tier 1).