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Note 4 - Loans - Impaired Loan Data (Details) - USD ($) | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018
Unpaid contractual principal balance with no related allowance | $ 20,682,000 | $ 15,967,000 | $ 19,810,000
Impaired balance with no related allowance | 19,769,000 | 15,857,000 | 19,703,000
Average recorded investment with no related allowance | 20,029,000 | 17,218,000 | 17,644,000
Interest income recognized with no related allowance | 383,000 | 348,000 | 904,000
Interest income collected with no related allowance | 456,000 | 356,000 | 949,000
Unpaid contractual principal balance with an allowance | 4,245,000 | 5,932,000 | 4,770,000
Impaired balance with an allowance | 4,245,000 | 5,932,000 | 4,770,000
Related allowance | 1,566,000 | 1,474,000 | 1,418,000
Average recorded investment with an allowance | 3,876,000 | 6,287,000 | 6,061,000
Interest income recognized with an allowance | 94,000 | 121,000 | 169,000
Interest income collected with an allowance | 118,000 | 114,000 | 177,000
Unpaid contractual principal balance | 25,572,000 | 21,899,000 | 24,580,000
Impaired balance | 24,179,000 | 21,789,000 | 24,473,000
Average recorded investment | 23,960,000 | 23,505,000 | 23,705,000
Interest income recognized | 477,000 | 469,000 | 1,073,000
Interest income collected | 574,000 | 470,000 | 1,126,000
Financial Asset Acquired with Credit Deterioration [Member] |  |  |
Related allowance |  | 0 | 0
Unpaid contractual principal balance | 645,000 |  |
Impaired balance | 165,000 | 0 | 0
Average recorded investment | 55,000 |  |
Interest income recognized |  |  |
Interest income collected |  |  |
Commercial and Agricultural Portfolio Segment [Member] | Commercial [Member] |  |  |
Unpaid contractual principal balance with no related allowance | 442,000 | 367,000 | 595,000
Impaired balance with no related allowance | 442,000 | 367,000 | 595,000
Average recorded investment with no related allowance | 525,000 | 520,000 | 526,000
Interest income recognized with no related allowance | 15,000 | 5,000 | 21,000
Interest income collected with no related allowance | 16,000 | 5,000 | 24,000
Unpaid contractual principal balance with an allowance | 0 | 0 | 42,000
Impaired balance with an allowance | 0 | 0 | 42,000
Related allowance |  | 0 | 6,000
Average recorded investment with an allowance | 14,000 | 0 | 8,000
Interest income recognized with an allowance | 0 | 0 | 2,000
Interest income collected with an allowance | 0 | 0 | 2,000
Unpaid contractual principal balance | 510,000 | 367,000 | 637,000
Impaired balance | 484,000 | 367,000 | 637,000
Average recorded investment | 553,000 | 520,000 | 534,000
Interest income recognized | 15,000 | 5,000 | 23,000
Interest income collected | 16,000 | 5,000 | 26,000
Commercial and Agricultural Portfolio Segment [Member] | Commercial [Member] | Financial Asset Acquired with Credit Deterioration [Member] |  |  |
Related allowance |  |  |
Unpaid contractual principal balance | 68,000 |  |
Impaired balance | 42,000 |  |
Average recorded investment | 14,000 |  |
Interest income recognized |  |  |
Interest income collected |  |  |
Commercial and Agricultural Portfolio Segment [Member] | Agricultural [Member] |  |  |
Unpaid contractual principal balance with no related allowance | 736,000 | 311,000 | 434,000
Impaired balance with no related allowance | 716,000 | 290,000 | 413,000
Average recorded investment with no related allowance | 544,000 | 360,000 | 383,000
Interest income recognized with no related allowance | 9,000 | 9,000 | 18,000
Interest income collected with no related allowance | 21,000 | 12,000 | 25,000
Unpaid contractual principal balance with an allowance | 588,000 | 0 | 0
Impaired balance with an allowance | 588,000 | 0 | 0
Related allowance | 588,000 | 0 | 0
Average recorded investment with an allowance | 196,000 | 0 | 0
Interest income recognized with an allowance | 9,000 | 0 | 0
Interest income collected with an allowance | 33,000 | 0 | 0
Unpaid contractual principal balance | 1,324,000 | 311,000 | 434,000
Impaired balance | 1,304,000 | 290,000 | 413,000
Average recorded investment | 740,000 | 360,000 | 383,000
Interest income recognized | 18,000 | 9,000 | 18,000
Interest income collected | 54,000 | 12,000 | 25,000
Commercial and Agricultural Portfolio Segment [Member] | Agricultural [Member] | Financial Asset Acquired with Credit Deterioration [Member] |  |  |
Related allowance |  |  |
Impaired balance |  |  |
Real Estate Portfolio Segment [Member] |  |  |
Interest income collected with an allowance |  | 0 |
Real Estate Portfolio Segment [Member] | Financial Asset Acquired with Credit Deterioration [Member] |  |  |
Impaired balance | 69,000 |  |
Real Estate Portfolio Segment [Member] | Commercial [Member] |  |  |
Unpaid contractual principal balance with no related allowance | 12,372,000 | 10,201,000 | 12,164,000
Impaired balance with no related allowance | 11,504,000 | 10,201,000 | 12,164,000
Average recorded investment with no related allowance | 12,341,000 | 11,092,000 | 11,040,000
Interest income recognized with no related allowance | 291,000 | 235,000 | 582,000
Interest income collected with no related allowance | 293,000 | 236,000 | 583,000
Unpaid contractual principal balance with an allowance | 3,031,000 | 5,047,000 | 3,691,000
Impaired balance with an allowance | 3,031,000 | 5,047,000 | 3,691,000
Related allowance | 897,000 | 1,371,000 | 1,276,000
Average recorded investment with an allowance | 2,902,000 | 5,371,000 | 5,121,000
Interest income recognized with an allowance | 61,000 | 106,000 | 135,000
Interest income collected with an allowance | 62,000 | 99,000 | 142,000
Unpaid contractual principal balance | 15,403,000 | 15,248,000 | 15,855,000
Impaired balance | 14,535,000 | 15,248,000 | 15,855,000
Average recorded investment | 15,243,000 | 16,463,000 | 16,161,000
Interest income recognized | 352,000 | 341,000 | 717,000
Interest income collected | 355,000 | 335,000 | 725,000
Real Estate Portfolio Segment [Member] | Commercial [Member] | Financial Asset Acquired with Credit Deterioration [Member] |  |  |
Related allowance |  |  |
Impaired balance |  |  |
Real Estate Portfolio Segment [Member] | Commercial Construction [Member] |  |  |
Unpaid contractual principal balance with no related allowance | 104,000 | 16,000 | 132,000
Impaired balance with no related allowance | 104,000 | 16,000 | 132,000
Average recorded investment with no related allowance | 115,000 | 38,000 | 69,000
Interest income recognized with no related allowance | 3,000 | 1,000 | 8,000
Interest income collected with no related allowance | 3,000 | 1,000 | 8,000
Unpaid contractual principal balance with an allowance |  | 482,000 | 399,000
Impaired balance with an allowance |  | 482,000 | 399,000
Related allowance |  | 54,000 | 39,000
Average recorded investment with an allowance | 133,000 | 487,000 | 466,000
Interest income recognized with an allowance |  | 2,000 | 0
Interest income collected with an allowance |  | 2,000 | 0
Unpaid contractual principal balance | 226,000 | 498,000 | 531,000
Impaired balance | 173,000 | 498,000 | 531,000
Average recorded investment | 271,000 | 525,000 | 535,000
Interest income recognized | 3,000 | 3,000 | 8,000
Interest income collected | 3,000 | 3,000 | 8,000
Real Estate Portfolio Segment [Member] | Commercial Construction [Member] | Financial Asset Acquired with Credit Deterioration [Member] |  |  |
Related allowance |  |  |
Unpaid contractual principal balance | 122,000 |  |
Impaired balance | 69,000 |  |
Average recorded investment | 23,000 |  |
Interest income recognized |  |  |
Interest income collected |  |  |
Real Estate Portfolio Segment [Member] | Residential Construction [Member] |  |  |
Unpaid contractual principal balance with no related allowance | 354,000 |  | 0
Impaired balance with no related allowance | 354,000 |  | 0
Average recorded investment with no related allowance | 118,000 |  | 0
Interest income recognized with no related allowance | 4,000 |  | 0
Interest income collected with no related allowance | 4,000 |  | 0
Unpaid contractual principal balance with an allowance | 0 | 0 | 0
Impaired balance with an allowance | 0 | 0 | 0
Related allowance |  | 0 | 0
Average recorded investment with an allowance | 0 | 0 | 0
Interest income recognized with an allowance | 0 | 0 | 0
Interest income collected with an allowance | 0 |  | 0
Unpaid contractual principal balance | 354,000 |  |
Impaired balance | 354,000 |  |
Average recorded investment | 118,000 |  | 0
Interest income recognized | 4,000 |  | 0
Interest income collected | 4,000 |  | 0
Real Estate Portfolio Segment [Member] | Residential Construction [Member] | Financial Asset Acquired with Credit Deterioration [Member] |  |  |
Related allowance |  |  |
Impaired balance |  |  |
Real Estate Portfolio Segment [Member] | Residential [Member] |  |  |
Unpaid contractual principal balance with no related allowance | 3,872,000 | 3,892,000 | 4,214,000
Impaired balance with no related allowance | 3,849,000 | 3,805,000 | 4,130,000
Average recorded investment with no related allowance | 3,979,000 | 4,113,000 | 4,067,000
Interest income recognized with no related allowance | 83,000 | 87,000 | 208,000
Interest income collected with no related allowance | 98,000 | 89,000 | 213,000
Unpaid contractual principal balance with an allowance | 267,000 | 36,000 | 274,000
Impaired balance with an allowance | 267,000 | 36,000 | 274,000
Related allowance | 49,000 | 21,000 | 61,000
Average recorded investment with an allowance | 270,000 | 60,000 | 98,000
Interest income recognized with an allowance | 11,000 | 1,000 | 8,000
Interest income collected with an allowance | 11,000 | 1,000 | 8,000
Unpaid contractual principal balance | 4,162,000 | 3,928,000 | 4,488,000
Impaired balance | 4,130,000 | 3,841,000 | 4,404,000
Average recorded investment | 4,254,000 | 4,173,000 | 4,165,000
Interest income recognized | 94,000 | 88,000 | 216,000
Interest income collected | 109,000 | 90,000 | 221,000
Real Estate Portfolio Segment [Member] | Residential [Member] | Financial Asset Acquired with Credit Deterioration [Member] |  |  |
Related allowance |  |  |
Unpaid contractual principal balance | 23,000 |  |
Impaired balance | 14,000 |  |
Average recorded investment | 5,000 |  |
Interest income recognized |  |  |
Interest income collected |  |  |
Real Estate Portfolio Segment [Member] | Farmland [Member] |  |  |
Unpaid contractual principal balance with no related allowance | 2,670,000 | 980,000 | 2,054,000
Impaired balance with no related allowance | 2,668,000 | 978,000 | 2,052,000
Average recorded investment with no related allowance | 2,246,000 | 896,000 | 1,361,000
Interest income recognized with no related allowance | (25,000) | 5,000 | 53,000
Interest income collected with no related allowance | 17,000 | 7,000 | 82,000
Unpaid contractual principal balance with an allowance | 359,000 | 367,000 | 364,000
Impaired balance with an allowance | 359,000 | 367,000 | 364,000
Related allowance | 32,000 | 28,000 | 36,000
Average recorded investment with an allowance | 361,000 | 369,000 | 368,000
Interest income recognized with an allowance | 13,000 | 12,000 | 24,000
Interest income collected with an allowance | 12,000 | 12,000 | 25,000
Unpaid contractual principal balance | 3,266,000 | 1,347,000 | 2,418,000
Impaired balance | 3,067,000 | 1,345,000 | 2,416,000
Average recorded investment | 2,620,000 | 1,265,000 | 1,729,000
Interest income recognized | (12,000) | 17,000 | 77,000
Interest income collected | 29,000 | 19,000 | 107,000
Real Estate Portfolio Segment [Member] | Farmland [Member] | Financial Asset Acquired with Credit Deterioration [Member] |  |  |
Related allowance |  |  |
Unpaid contractual principal balance | 237,000 |  |
Impaired balance | 40,000 |  |
Average recorded investment | 13,000 |  |
Interest income recognized |  |  |
Interest income collected |  |  |
Consumer and Other Portfolio Segment [Member] | Consumer [Member] |  |  |
Unpaid contractual principal balance with no related allowance | 132,000 | 200,000 | 213,000
Impaired balance with no related allowance | 132,000 | 200,000 | 213,000
Average recorded investment with no related allowance | 159,000 | 199,000 | 197,000
Interest income recognized with no related allowance | 3,000 | 6,000 | 14,000
Interest income collected with no related allowance | 4,000 | 6,000 | 14,000
Unpaid contractual principal balance with an allowance | 0 | 0 | 0
Impaired balance with an allowance | 0 | 0 | 0
Related allowance |  | 0 | 0
Average recorded investment with an allowance | 0 | 0 | 0
Interest income recognized with an allowance | 0 | 0 | 0
Interest income collected with an allowance | 0 | 0 | 0
Unpaid contractual principal balance | 327,000 | 200,000 | 213,000
Impaired balance | 132,000 | 200,000 | 213,000
Average recorded investment | 159,000 | 199,000 | 197,000
Interest income recognized | 3,000 | 6,000 | 14,000
Interest income collected | 4,000 | 6,000 | 14,000
Consumer and Other Portfolio Segment [Member] | Consumer [Member] | Financial Asset Acquired with Credit Deterioration [Member] |  |  |
Related allowance |  |  |
Unpaid contractual principal balance | 195,000 |  |
Impaired balance |  |  |
Average recorded investment |  |  |
Interest income recognized |  |  |
Interest income collected |  |  |
Consumer and Other Portfolio Segment [Member] | Other [Member] |  |  |
Unpaid contractual principal balance with no related allowance |  | 0 | 4,000
Impaired balance with no related allowance |  | 0 | 4,000
Average recorded investment with no related allowance | 2,000 | 0 | 1,000
Interest income recognized with no related allowance |  | 0 | 0
Interest income collected with no related allowance |  | 0 | 0
Unpaid contractual principal balance with an allowance |  | 0 |
Impaired balance with an allowance |  | 0 |
Related allowance |  | 0 | 0
Average recorded investment with an allowance |  | 0 | 0
Interest income recognized with an allowance |  | 0 | 0
Interest income collected with an allowance |  | 0 | 0
Unpaid contractual principal balance |  | 0 | 4,000
Impaired balance |  | 0 | 4,000
Average recorded investment | 2,000 | 0 | 1,000
Interest income recognized |  | 0 | 0
Interest income collected |  | $ 0 | $ 0
Consumer and Other Portfolio Segment [Member] | Other [Member] | Financial Asset Acquired with Credit Deterioration [Member] |  |  |
Related allowance |  |  |
Impaired balance |  |  |

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