Note 12 - Regulatory Capital Matters (Details) - Regulatory Capital Information - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Total Capital to Risk-Weighted Assets
Capital	$ 135,304	$ 136,022
Capital to Risk-Weighted Assets	17.01%	17.95%
Capital Required for Capital Adequacy	$ 63,628	$ 60,639
Capital Required for Capital Adequacy to Risk-Weighted Assets	8.00%	8.00%
Capital Required to be Well Capitalized
Capital Requited to be Well Capitalized to Risk-Weighted Assets
Tier I Capital to Risk-Weighted Assets
Tier I Risk Based Capital	$ 126,904	$ 127,220
Tier I Risk Based Capital to Risk-Weighted Assets	15.96%	16.78%
Tier I Risk Based Capital Required for Capital Adequacy	$ 47,721	$ 30,320
Tier I Risk Based Capital Required for Capital Adequacy to Risk-Weighted Assets	6.00%	4.00%
Tier I Risk Based Capital Required to be Well Capitalized
Tier I Risk Based Capital Required to be Well Capitalized to Risk-Weighted Assets
Common Equity Tier I Capital to Risk-Weighted Assets
Common Equity Tier I Risk Based Capital	$ 80,237
Common Equity Tier I Risk Based Capital to Risk-Weighted Assets	10.09%
Common Equity Tier I Risk Based Capital Required for Capital Adequacy	$ 35,791
Common Equity Tier I Risk Based Capital Required for Capital Adequacy to Risk-Weighted Assets	4.50%
Common Equity Tier I Risk Based Capital Required to Be Well Capitalized
Common Equity Tier I Risk Based Capital Required to Be Well Capitalized to Risk-Weighted Assets
Tier I Capital to Average Assets
Tier I Leverage Capital	$ 126,904	$ 127,220
Tier I Leverage Capital to Average Assets	11.14%	11.18%
Tier I Leverage Capital Required for Capital Adequacy	$ 45,571	$ 45,509
Tier I Leverage Capital Required for Capital Adequacy to Average Assets	4.00%	4.00%
Tier I Leverage Capital Required to Be Well Capitalized
Tier I Leverage Capital Required to Be Well Capitalized to Average Assets
Colony Bank [Member]
Total Capital to Risk-Weighted Assets
Capital	$ 130,450	$ 127,833
Capital to Risk-Weighted Assets	16.43%	16.89%
Capital Required for Capital Adequacy	$ 63,536	$ 60,542
Capital Required for Capital Adequacy to Risk-Weighted Assets	8.00%	8.00%
Capital Required to be Well Capitalized	$ 79,421	$ 75,678
Capital Requited to be Well Capitalized to Risk-Weighted Assets	10.00%	10.00%
Tier I Capital to Risk-Weighted Assets
Tier I Risk Based Capital	$ 122,048	$ 119,031
Tier I Risk Based Capital to Risk-Weighted Assets	15.37%	15.73%
Tier I Risk Based Capital Required for Capital Adequacy	$ 47,652	$ 30,271
Tier I Risk Based Capital Required for Capital Adequacy to Risk-Weighted Assets	6.00%	4.00%
Tier I Risk Based Capital Required to be Well Capitalized	$ 63,536	$ 45,407
Tier I Risk Based Capital Required to be Well Capitalized to Risk-Weighted Assets	8.00%	6.00%
Common Equity Tier I Capital to Risk-Weighted Assets
Common Equity Tier I Risk Based Capital	$ 122,048
Common Equity Tier I Risk Based Capital to Risk-Weighted Assets	15.37%
Common Equity Tier I Risk Based Capital Required for Capital Adequacy	$ 35,739
Common Equity Tier I Risk Based Capital Required for Capital Adequacy to Risk-Weighted Assets	4.50%
Common Equity Tier I Risk Based Capital Required to Be Well Capitalized	$ 51,623
Common Equity Tier I Risk Based Capital Required to Be Well Capitalized to Risk-Weighted Assets	6.50%
Tier I Capital to Average Assets
Tier I Leverage Capital	$ 122,048	$ 119,031
Tier I Leverage Capital to Average Assets	10.73%	10.50%
Tier I Leverage Capital Required for Capital Adequacy	$ 45,496	$ 45,364
Tier I Leverage Capital Required for Capital Adequacy to Average Assets	4.00%	4.00%
Tier I Leverage Capital Required to Be Well Capitalized	$ 56,870	$ 56,705
Tier I Leverage Capital Required to Be Well Capitalized to Average Assets	5.00%	5.00%

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