Note 18 - Regulatory Matters - Regulatory Ratios of the Consolidated Company and Its Subsidiary Banks (Details) - USD ($)
Dec. 31, 2016
Dec. 31, 2015
Consolidated Entities [Member]    
Common Equity Tier 1 Risk-based Capital, actual, amount [1] $ 187,474,000 $ 172,871,000
Common Equity Tier 1 Risk-based Capital, actual, ratio [1] 16.43% 14.91%
Common Equity Tier 1 Risk-based Capital, for Capital Adequacy Purposes, amount [1] $ 51,349,000 $ 52,184,000
Common Equity Tier 1 Risk-based Capital, for Capital Adequacy Purposes, ratio [1] 4.50% 4.50%
Common Equity Tier 1 Risk-based Capital, to Be Well-capitalized, amount  
Common Equity Tier 1 Risk-based Capital, to Be Well-capitalized, ratio  
Tier 1 Risk-based Capital, actual, amount [1] $ 219,974,000 $ 220,371
Tier 1 Risk-based Capital, actual, ratio [1] 19.28% 19.00%
Tier 1 Risk-based Capital, for Capital Adequacy Purposes, amount [1] $ 68,466,000 $ 69,579
Tier 1 Risk-based Capital, for Capital Adequacy Purposes, ratio [1] 6.00% 6.00%
Tier 1 Risk-based Capital, to Be Well-capitalized, amount  
Tier 1 Risk-based Capital, to Be Well-capitalized, ratio  
Total Risk-based Capital, actual, amount $ 229,318,000 [1] $ 230,686 [2]
Total Risk-based Capital, actual, ratio 20.10% [1] 19.89% [2]
Total Risk-based Capital, for Capital Adequacy Purposes, amount $ 91,288,000 [1] $ 92,772 [2]
Total Risk-based Capital, for Capital Adequacy Purposes, ratio 8.00% [1] 8.00% [2]
Total Risk-based Capital, to Be Well-capitalized, amount  
Total Risk-based Capital, to Be Well-capitalized, ratio  
Tier 1 Leverage Capital, actual, amount $ 219,974,000 [2] $ 220,371
Tier 1 Leverage Capital, actual, ratio 13.20% [2] 12.46%
Tier 1 Leverage Capital, for Capital Adequacy Purposes, amount $ 66,656,000 [2] $ 70,746
Tier 1 Leverage Capital, for Capital Adequacy Purposes, ratio 4.00% [2] 4.00%
Ter 1 Leverage Capital, to Be Well-capitalized, amount [2]
Tier 1 Leverage Capital, to Be Well-capitalized, ratio [2]
Farmers Bank [Member]    
Common Equity Tier 1 Risk-based Capital, actual, amount [1] $ 64,016,000 $ 63,552
Common Equity Tier 1 Risk-based Capital, actual, ratio [1] 16.53% 15.57%
Common Equity Tier 1 Risk-based Capital, for Capital Adequacy Purposes, amount [1] $ 17,425,000 $ 18,366
Common Equity Tier 1 Risk-based Capital, for Capital Adequacy Purposes, ratio [1] 4.50% 4.50%
Common Equity Tier 1 Risk-based Capital, to Be Well-capitalized, amount [1] $ 25,170,000 $ 26,529
Common Equity Tier 1 Risk-based Capital, to Be Well-capitalized, ratio [1] 6.50% 6.50%
Tier 1 Risk-based Capital, actual, amount [1] $ 64,016,000 $ 63,552
Tier 1 Risk-based Capital, actual, ratio [1] 16.53% 15.57%
Tier 1 Risk-based Capital, for Capital Adequacy Purposes, amount [1] $ 23,234,000 $ 24,488
Tier 1 Risk-based Capital, for Capital Adequacy Purposes, ratio [1] 6.00% 6.00%
Tier 1 Risk-based Capital, to Be Well-capitalized, amount [1] $ 30,978,000 $ 32,651
Tier 1 Risk-based Capital, to Be Well-capitalized, ratio [1] 8.00% 8.00%
Total Risk-based Capital, actual, amount $ 66,720,000 [1] $ 66,728 [2]
Total Risk-based Capital, actual, ratio 17.23% [1] 16.35% [2]
Total Risk-based Capital, for Capital Adequacy Purposes, amount $ 30,978,000 [1] $ 32,651 [2]
Total Risk-based Capital, for Capital Adequacy Purposes, ratio 8.00% [1] 8.00% [2]
Total Risk-based Capital, to Be Well-capitalized, amount $ 38,723,000 [1] $ 40,814 [2]
Total Risk-based Capital, to Be Well-capitalized, ratio 10.00% [1] 10.00% [2]
Tier 1 Leverage Capital, actual, amount $ 64,016,000 [2] $ 63,552
Tier 1 Leverage Capital, actual, ratio 9.80% [2] 9.20%
Tier 1 Leverage Capital, for Capital Adequacy Purposes, amount $ 26,121,000 [2] $ 27,629
Tier 1 Leverage Capital, for Capital Adequacy Purposes, ratio 4.00% [2] 4.00%
Ter 1 Leverage Capital, to Be Well-capitalized, amount $ 32,651,000 [2] $ 34,537
Tier 1 Leverage Capital, to Be Well-capitalized, ratio 5.00% [2] 5.00%
United Bank [Member]    
Common Equity Tier 1 Risk-based Capital, actual, amount [1] $ 58,180,000 $ 65,862
Common Equity Tier 1 Risk-based Capital, actual, ratio [1] 15.54% 18.67%
Common Equity Tier 1 Risk-based Capital, for Capital Adequacy Purposes, amount [1] $ 16,848,000 $ 15,879
Common Equity Tier 1 Risk-based Capital, for Capital Adequacy Purposes, ratio [1] 4.50% 4.50%
Common Equity Tier 1 Risk-based Capital, to Be Well-capitalized, amount [1] $ 24,337,000 $ 22,936
Common Equity Tier 1 Risk-based Capital, to Be Well-capitalized, ratio [1] 6.50% 6.50%
Tier 1 Risk-based Capital, actual, amount [1] $ 58,180,000 $ 65,862
Tier 1 Risk-based Capital, actual, ratio [1] 15.54% 18.67%
Tier 1 Risk-based Capital, for Capital Adequacy Purposes, amount [1] $ 22,465,000 $ 21,171
Tier 1 Risk-based Capital, for Capital Adequacy Purposes, ratio [1] 6.00% 6.00%
Tier 1 Risk-based Capital, to Be Well-capitalized, amount [1] $ 29,953,000 $ 28,228
Tier 1 Risk-based Capital, to Be Well-capitalized, ratio [1] 8.00% 8.00%
Total Risk-based Capital, actual, amount $ 61,680,000 [1] $ 69,456 [2]
Total Risk-based Capital, actual, ratio 16.47% [1] 19.68% [2]
Total Risk-based Capital, for Capital Adequacy Purposes, amount $ 29,953,000 [1] $ 28,228 [2]
Total Risk-based Capital, for Capital Adequacy Purposes, ratio 8.00% [1] 8.00% [2]
Total Risk-based Capital, to Be Well-capitalized, amount $ 37,441,000 [1] $ 35,286 [2]
Total Risk-based Capital, to Be Well-capitalized, ratio 10.00% [1] 10.00% [2]
Tier 1 Leverage Capital, actual, amount $ 58,180,000 [2] $ 65,862
Tier 1 Leverage Capital, actual, ratio 12.38% [2] 12.89%
Tier 1 Leverage Capital, for Capital Adequacy Purposes, amount $ 18,798,000 [2] $ 20,442
Tier 1 Leverage Capital, for Capital Adequacy Purposes, ratio 4.00% [2] 4.00%
Ter 1 Leverage Capital, to Be Well-capitalized, amount $ 23,497,000 [2] $ 25,553
Tier 1 Leverage Capital, to Be Well-capitalized, ratio 5.00% [2] 5.00%
First Citizens Bank [Member]    
Common Equity Tier 1 Risk-based Capital, actual, amount [1] $ 28,324,000 $ 28,743
Common Equity Tier 1 Risk-based Capital, actual, ratio [1] 13.56% 13.55%
Common Equity Tier 1 Risk-based Capital, for Capital Adequacy Purposes, amount [1] $ 9,401,000 $ 9,543
Common Equity Tier 1 Risk-based Capital, for Capital Adequacy Purposes, ratio [1] 4.50% 4.50%
Common Equity Tier 1 Risk-based Capital, to Be Well-capitalized, amount [1] $ 13,580,000 $ 13,784
Common Equity Tier 1 Risk-based Capital, to Be Well-capitalized, ratio [1] 6.50% 6.50%
Tier 1 Risk-based Capital, actual, amount [1] $ 28,324,000  
Tier 1 Risk-based Capital, actual, ratio [1] 13.56% 13.55%
Tier 1 Risk-based Capital, for Capital Adequacy Purposes, amount [1] $ 12,535,000 $ 12,724
Tier 1 Risk-based Capital, for Capital Adequacy Purposes, ratio [1] 6.00% 6.00%
Tier 1 Risk-based Capital, to Be Well-capitalized, amount [1] $ 16,714,000 $ 16,965
Tier 1 Risk-based Capital, to Be Well-capitalized, ratio [1] 8.00% 8.00%
Total Risk-based Capital, actual, amount $ 29,590,000 [1] $ 30,048 [2]
Total Risk-based Capital, actual, ratio 14.16% [1] 14.17% [2]
Total Risk-based Capital, for Capital Adequacy Purposes, amount $ 16,714,000 [1] $ 16,965 [2]
Total Risk-based Capital, for Capital Adequacy Purposes, ratio 8.00% [1] 8.00% [2]
Total Risk-based Capital, to Be Well-capitalized, amount $ 20,892,000 [1] $ 21,207 [2]
Total Risk-based Capital, to Be Well-capitalized, ratio 10.00% [1] 10.00% [2]
Tier 1 Leverage Capital, actual, amount $ 28,324,000 [2] $ 28,743
Tier 1 Leverage Capital, actual, ratio 9.76% [2] 9.20%
Tier 1 Leverage Capital, for Capital Adequacy Purposes, amount $ 11,606,000 [2] $ 12,493
Tier 1 Leverage Capital, for Capital Adequacy Purposes, ratio 4.00% [2] 4.00%
Ter 1 Leverage Capital, to Be Well-capitalized, amount $ 14,507,000 [2] $ 15,617
Tier 1 Leverage Capital, to Be Well-capitalized, ratio 5.00% [2] 5.00%
Citizens Northern [Member]    
Common Equity Tier 1 Risk-based Capital, actual, amount [1] $ 24,661,000 $ 25,770
Common Equity Tier 1 Risk-based Capital, actual, ratio [1] 15.24% 14.42%
Common Equity Tier 1 Risk-based Capital, for Capital Adequacy Purposes, amount [1] $ 7,280,000 $ 8,044
Common Equity Tier 1 Risk-based Capital, for Capital Adequacy Purposes, ratio [1] 4.50% 4.50%
Common Equity Tier 1 Risk-based Capital, to Be Well-capitalized, amount [1] $ 10,516,000 $ 11,619
Common Equity Tier 1 Risk-based Capital, to Be Well-capitalized, ratio [1] 6.50% 6.50%
Tier 1 Risk-based Capital, actual, amount [1] $ 24,661,000 $ 25,770
Tier 1 Risk-based Capital, actual, ratio [1] 15.24% 14.42%
Tier 1 Risk-based Capital, for Capital Adequacy Purposes, amount [1] $ 9,707,000 $ 10,725
Tier 1 Risk-based Capital, for Capital Adequacy Purposes, ratio [1] 6.00% 6.00%
Tier 1 Risk-based Capital, to Be Well-capitalized, amount [1] $ 12,942,000 $ 14,300
Tier 1 Risk-based Capital, to Be Well-capitalized, ratio [1] 8.00% 8.00%
Total Risk-based Capital, actual, amount $ 26,534,000 [1] $ 28,004 [2]
Total Risk-based Capital, actual, ratio 16.40% [1] 15.67% [2]
Total Risk-based Capital, for Capital Adequacy Purposes, amount $ 12,942,000 [1] $ 14,300 [2]
Total Risk-based Capital, for Capital Adequacy Purposes, ratio 8.00% [1] 8.00% [2]
Total Risk-based Capital, to Be Well-capitalized, amount $ 16,178,000 [1] $ 17,875 [2]
Total Risk-based Capital, to Be Well-capitalized, ratio 10.00% [1] 10.00% [2]
Tier 1 Leverage Capital, actual, amount $ 24,661,000 [2] $ 25,770
Tier 1 Leverage Capital, actual, ratio 10.68% [2] 10.79%
Tier 1 Leverage Capital, for Capital Adequacy Purposes, amount $ 9,234,000 [2] $ 9,555
Tier 1 Leverage Capital, for Capital Adequacy Purposes, ratio 4.00% [2] 4.00%
Ter 1 Leverage Capital, to Be Well-capitalized, amount $ 11,543,000 [2] $ 11,943
Tier 1 Leverage Capital, to Be Well-capitalized, ratio 5.00% [2] 5.00%
[1] Common Equity Tier 1 Risk-based, Tier 1 Risk-based, and Total Risk-based Capital ratios are computed by dividing a bank's Common Equity Tier 1, Tier 1, or Total Capital, as defined by regulation, by a risk-weighted sum of the bank's assets, with the risk weighting determined by general standards established by regulation.
[2] Tier 1 Leverage ratio is computed by dividing a bank's Tier 1 Capital by its total quarterly average assets, as defined by regulation.