Loans, Impaired Financing Receivable (Details) (USD $) | 9 Months Ended | 12 Months Ended |
In Thousands, unless otherwise specified | Sep. 30, 2013 | Sep. 30, 2012 | Dec. 31, 2012 |
Unpaid Contractual Principal Balance [Abstract] | ' | ' | ' |
Unpaid Contractual Principal Balance With No Related Allowance Recorded | $27,110 | $52,977 | $36,332 |
Unpaid Contractual Principal Balance With An Allowance Recorded | 26,583 | 24,057 | 28,034 |
Unpaid Contractual Principal Balance, Total | 53,693 | 77,034 | 64,366 |
Impaired Balance [Abstract] | ' | ' | ' |
Impaired Balance With No Related Allowance Recorded | 21,727 | 44,699 | 29,820 |
Impaired Balance With An Allowance Recorded | 24,132 | 20,893 | 26,278 |
Impaired Balance, Total | 45,859 | 65,592 | 56,098 |
Related Allowance [Abstract] | ' | ' | ' |
Related Allowance With No Related Allowance Recorded | 0 | 0 | 0 |
Related Allowance With An Allowance Recorded | 3,216 | 4,214 | 4,272 |
Related Allowance, Total | 3,216 | 4,214 | 4,272 |
Average Recorded Investment [Abstract] | ' | ' | ' |
Average Recorded Investment With No Related Allowance Recorded | 14,605 | 46,676 | 42,461 |
Average Recorded Investment With An Allowance Recorded | 16,782 | 20,878 | 22,229 |
Average Recorded Investment, Total | 31,387 | 67,554 | 64,690 |
Interest Income Recognized [Abstract] | ' | ' | ' |
Interest Income Recognized With No Related Allowance Recorded | 292 | 793 | 627 |
Interest Income Recognized With An Allowance Recorded | 410 | 264 | 621 |
Interest Income Recognized, Total | 702 | 1,057 | 1,248 |
Interest Income Collected [Abstract] | ' | ' | ' |
Interest Income Collected With No Related Allowance Recorded | 316 | 837 | 693 |
Interest Income Collected With An Allowance Recorded | 415 | 262 | 571 |
Interest Income Collected, Total | 731 | 1,099 | 1,264 |
Commercial [Member] | ' | ' | ' |
Unpaid Contractual Principal Balance [Abstract] | ' | ' | ' |
Unpaid Contractual Principal Balance With No Related Allowance Recorded | 266 | 85 | 1,508 |
Unpaid Contractual Principal Balance With An Allowance Recorded | 1,465 | 1,677 | 1,493 |
Unpaid Contractual Principal Balance, Total | 1,731 | 1,762 | 3,001 |
Impaired Balance [Abstract] | ' | ' | ' |
Impaired Balance With No Related Allowance Recorded | 265 | 34 | 1,042 |
Impaired Balance With An Allowance Recorded | 1,465 | 1,677 | 1,493 |
Impaired Balance, Total | 1,730 | 1,711 | 2,535 |
Related Allowance [Abstract] | ' | ' | ' |
Related Allowance With No Related Allowance Recorded | 0 | 0 | 0 |
Related Allowance With An Allowance Recorded | 108 | 514 | 463 |
Related Allowance, Total | 108 | 514 | 463 |
Average Recorded Investment [Abstract] | ' | ' | ' |
Average Recorded Investment With No Related Allowance Recorded | 98 | 1,056 | 1,053 |
Average Recorded Investment With An Allowance Recorded | 1,280 | 759 | 943 |
Average Recorded Investment, Total | 1,378 | 1,815 | 1,996 |
Interest Income Recognized [Abstract] | ' | ' | ' |
Interest Income Recognized With No Related Allowance Recorded | 11 | 4 | 27 |
Interest Income Recognized With An Allowance Recorded | 14 | 69 | 92 |
Interest Income Recognized, Total | 25 | 73 | 119 |
Interest Income Collected [Abstract] | ' | ' | ' |
Interest Income Collected With No Related Allowance Recorded | 14 | 2 | 28 |
Interest Income Collected With An Allowance Recorded | 19 | 64 | 88 |
Interest Income Collected, Total | 33 | 66 | 116 |
Agricultural [Member] | ' | ' | ' |
Unpaid Contractual Principal Balance [Abstract] | ' | ' | ' |
Unpaid Contractual Principal Balance With No Related Allowance Recorded | 0 | 109 | 39 |
Unpaid Contractual Principal Balance With An Allowance Recorded | 0 | 0 | 0 |
Unpaid Contractual Principal Balance, Total | 0 | 109 | 39 |
Impaired Balance [Abstract] | ' | ' | ' |
Impaired Balance With No Related Allowance Recorded | 0 | 109 | 39 |
Impaired Balance With An Allowance Recorded | 0 | 0 | 0 |
Impaired Balance, Total | 0 | 109 | 39 |
Related Allowance [Abstract] | ' | ' | ' |
Related Allowance With No Related Allowance Recorded | 0 | 0 | 0 |
Related Allowance With An Allowance Recorded | 0 | 0 | 0 |
Related Allowance, Total | 0 | 0 | 0 |
Average Recorded Investment [Abstract] | ' | ' | ' |
Average Recorded Investment With No Related Allowance Recorded | 13 | 64 | 58 |
Average Recorded Investment With An Allowance Recorded | 0 | 0 | 0 |
Average Recorded Investment, Total | 13 | 64 | 58 |
Interest Income Recognized [Abstract] | ' | ' | ' |
Interest Income Recognized With No Related Allowance Recorded | 0 | 8 | 0 |
Interest Income Recognized With An Allowance Recorded | 0 | 0 | 0 |
Interest Income Recognized, Total | 0 | 8 | 0 |
Interest Income Collected [Abstract] | ' | ' | ' |
Interest Income Collected With No Related Allowance Recorded | 0 | 18 | 0 |
Interest Income Collected With An Allowance Recorded | 0 | 0 | 0 |
Interest Income Collected, Total | 0 | 18 | 0 |
Commercial Construction [Member] | ' | ' | ' |
Unpaid Contractual Principal Balance [Abstract] | ' | ' | ' |
Unpaid Contractual Principal Balance With No Related Allowance Recorded | 8,335 | 10,527 | 10,625 |
Unpaid Contractual Principal Balance With An Allowance Recorded | 5,924 | 12,331 | 8,267 |
Unpaid Contractual Principal Balance, Total | 14,259 | 22,858 | 18,892 |
Impaired Balance [Abstract] | ' | ' | ' |
Impaired Balance With No Related Allowance Recorded | 5,010 | 8,205 | 6,415 |
Impaired Balance With An Allowance Recorded | 3,473 | 10,610 | 7,618 |
Impaired Balance, Total | 8,483 | 18,815 | 14,033 |
Related Allowance [Abstract] | ' | ' | ' |
Related Allowance With No Related Allowance Recorded | 0 | 0 | 0 |
Related Allowance With An Allowance Recorded | 573 | 1,786 | 1,733 |
Related Allowance, Total | 573 | 1,786 | 1,733 |
Average Recorded Investment [Abstract] | ' | ' | ' |
Average Recorded Investment With No Related Allowance Recorded | 2,220 | 10,121 | 9,194 |
Average Recorded Investment With An Allowance Recorded | 4,386 | 11,506 | 10,534 |
Average Recorded Investment, Total | 6,606 | 21,627 | 19,728 |
Interest Income Recognized [Abstract] | ' | ' | ' |
Interest Income Recognized With No Related Allowance Recorded | 17 | -9 | 27 |
Interest Income Recognized With An Allowance Recorded | 0 | 1 | 0 |
Interest Income Recognized, Total | 17 | -8 | 27 |
Interest Income Collected [Abstract] | ' | ' | ' |
Interest Income Collected With No Related Allowance Recorded | 23 | 1 | 52 |
Interest Income Collected With An Allowance Recorded | 0 | 4 | 0 |
Interest Income Collected, Total | 23 | 5 | 52 |
Commercial Real Estate [Member] | ' | ' | ' |
Unpaid Contractual Principal Balance [Abstract] | ' | ' | ' |
Unpaid Contractual Principal Balance With No Related Allowance Recorded | 8,559 | 35,399 | 16,566 |
Unpaid Contractual Principal Balance With An Allowance Recorded | 15,061 | 4,789 | 12,759 |
Unpaid Contractual Principal Balance, Total | 23,620 | 40,188 | 29,325 |
Impaired Balance [Abstract] | ' | ' | ' |
Impaired Balance With No Related Allowance Recorded | 8,064 | 30,152 | 15,506 |
Impaired Balance With An Allowance Recorded | 15,061 | 4,059 | 12,745 |
Impaired Balance, Total | 23,125 | 34,211 | 28,251 |
Related Allowance [Abstract] | ' | ' | ' |
Related Allowance With No Related Allowance Recorded | 0 | 0 | 0 |
Related Allowance With An Allowance Recorded | 1,559 | 864 | 1,236 |
Related Allowance, Total | 1,559 | 864 | 1,236 |
Average Recorded Investment [Abstract] | ' | ' | ' |
Average Recorded Investment With No Related Allowance Recorded | 8,493 | 30,141 | 26,482 |
Average Recorded Investment With An Allowance Recorded | 7,785 | 4,282 | 6,399 |
Average Recorded Investment, Total | 16,278 | 34,423 | 32,881 |
Interest Income Recognized [Abstract] | ' | ' | ' |
Interest Income Recognized With No Related Allowance Recorded | 95 | 670 | 430 |
Interest Income Recognized With An Allowance Recorded | 287 | 115 | 384 |
Interest Income Recognized, Total | 382 | 785 | 814 |
Interest Income Collected [Abstract] | ' | ' | ' |
Interest Income Collected With No Related Allowance Recorded | 113 | 667 | 421 |
Interest Income Collected With An Allowance Recorded | 285 | 116 | 366 |
Interest Income Collected, Total | 398 | 783 | 787 |
Residential Real Estate [Member] | ' | ' | ' |
Unpaid Contractual Principal Balance [Abstract] | ' | ' | ' |
Unpaid Contractual Principal Balance With No Related Allowance Recorded | 7,378 | 4,291 | 4,450 |
Unpaid Contractual Principal Balance With An Allowance Recorded | 2,804 | 5,260 | 5,515 |
Unpaid Contractual Principal Balance, Total | 10,182 | 9,551 | 9,965 |
Impaired Balance [Abstract] | ' | ' | ' |
Impaired Balance With No Related Allowance Recorded | 5,830 | 3,694 | 4,132 |
Impaired Balance With An Allowance Recorded | 2,804 | 4,547 | 4,422 |
Impaired Balance, Total | 8,634 | 8,241 | 8,554 |
Related Allowance [Abstract] | ' | ' | ' |
Related Allowance With No Related Allowance Recorded | 0 | 0 | 0 |
Related Allowance With An Allowance Recorded | 774 | 1,050 | 840 |
Related Allowance, Total | 774 | 1,050 | 840 |
Average Recorded Investment [Abstract] | ' | ' | ' |
Average Recorded Investment With No Related Allowance Recorded | 2,022 | 2,751 | 3,096 |
Average Recorded Investment With An Allowance Recorded | 3,331 | 4,244 | 4,288 |
Average Recorded Investment, Total | 5,353 | 6,995 | 7,384 |
Interest Income Recognized [Abstract] | ' | ' | ' |
Interest Income Recognized With No Related Allowance Recorded | 157 | 84 | 89 |
Interest Income Recognized With An Allowance Recorded | 65 | 79 | 145 |
Interest Income Recognized, Total | 222 | 163 | 234 |
Interest Income Collected [Abstract] | ' | ' | ' |
Interest Income Collected With No Related Allowance Recorded | 152 | 99 | 123 |
Interest Income Collected With An Allowance Recorded | 64 | 78 | 117 |
Interest Income Collected, Total | 216 | 177 | 240 |
Farmland [Member] | ' | ' | ' |
Unpaid Contractual Principal Balance [Abstract] | ' | ' | ' |
Unpaid Contractual Principal Balance With No Related Allowance Recorded | 2,277 | 2,340 | 2,829 |
Unpaid Contractual Principal Balance With An Allowance Recorded | 1,329 | 0 | 0 |
Unpaid Contractual Principal Balance, Total | 3,606 | 2,340 | 2,829 |
Impaired Balance [Abstract] | ' | ' | ' |
Impaired Balance With No Related Allowance Recorded | 2,277 | 2,297 | 2,413 |
Impaired Balance With An Allowance Recorded | 1,329 | 0 | 0 |
Impaired Balance, Total | 3,606 | 2,297 | 2,413 |
Related Allowance [Abstract] | ' | ' | ' |
Related Allowance With No Related Allowance Recorded | 0 | 0 | 0 |
Related Allowance With An Allowance Recorded | 202 | 0 | 0 |
Related Allowance, Total | 202 | 0 | 0 |
Average Recorded Investment [Abstract] | ' | ' | ' |
Average Recorded Investment With No Related Allowance Recorded | 1,618 | 2,297 | 2,326 |
Average Recorded Investment With An Allowance Recorded | 0 | 87 | 65 |
Average Recorded Investment, Total | 1,618 | 2,384 | 2,391 |
Interest Income Recognized [Abstract] | ' | ' | ' |
Interest Income Recognized With No Related Allowance Recorded | 0 | 31 | 43 |
Interest Income Recognized With An Allowance Recorded | 44 | 0 | 0 |
Interest Income Recognized, Total | 44 | 31 | 43 |
Interest Income Collected [Abstract] | ' | ' | ' |
Interest Income Collected With No Related Allowance Recorded | 0 | 44 | 55 |
Interest Income Collected With An Allowance Recorded | 47 | 0 | 0 |
Interest Income Collected, Total | 47 | 44 | 55 |
Consumer [Member] | ' | ' | ' |
Unpaid Contractual Principal Balance [Abstract] | ' | ' | ' |
Unpaid Contractual Principal Balance With No Related Allowance Recorded | 295 | 226 | 297 |
Unpaid Contractual Principal Balance With An Allowance Recorded | 0 | 0 | 0 |
Unpaid Contractual Principal Balance, Total | 295 | 226 | 297 |
Impaired Balance [Abstract] | ' | ' | ' |
Impaired Balance With No Related Allowance Recorded | 281 | 208 | 255 |
Impaired Balance With An Allowance Recorded | 0 | 0 | 0 |
Impaired Balance, Total | 281 | 208 | 255 |
Related Allowance [Abstract] | ' | ' | ' |
Related Allowance With No Related Allowance Recorded | 0 | 0 | 0 |
Related Allowance With An Allowance Recorded | 0 | 0 | 0 |
Related Allowance, Total | 0 | 0 | 0 |
Average Recorded Investment [Abstract] | ' | ' | ' |
Average Recorded Investment With No Related Allowance Recorded | 141 | 219 | 228 |
Average Recorded Investment With An Allowance Recorded | 0 | 0 | 0 |
Average Recorded Investment, Total | 141 | 219 | 228 |
Interest Income Recognized [Abstract] | ' | ' | ' |
Interest Income Recognized With No Related Allowance Recorded | 12 | 5 | 10 |
Interest Income Recognized With An Allowance Recorded | 0 | 0 | 0 |
Interest Income Recognized, Total | 12 | 5 | 10 |
Interest Income Collected [Abstract] | ' | ' | ' |
Interest Income Collected With No Related Allowance Recorded | 14 | 6 | 13 |
Interest Income Collected With An Allowance Recorded | 0 | 0 | 0 |
Interest Income Collected, Total | 14 | 6 | 13 |
Other [Member] | ' | ' | ' |
Unpaid Contractual Principal Balance [Abstract] | ' | ' | ' |
Unpaid Contractual Principal Balance With No Related Allowance Recorded | 0 | 0 | 18 |
Unpaid Contractual Principal Balance With An Allowance Recorded | 0 | 0 | 0 |
Unpaid Contractual Principal Balance, Total | 0 | 0 | 18 |
Impaired Balance [Abstract] | ' | ' | ' |
Impaired Balance With No Related Allowance Recorded | 0 | 0 | 18 |
Impaired Balance With An Allowance Recorded | 0 | 0 | 0 |
Impaired Balance, Total | 0 | 0 | 18 |
Related Allowance [Abstract] | ' | ' | ' |
Related Allowance With No Related Allowance Recorded | 0 | 0 | 0 |
Related Allowance With An Allowance Recorded | 0 | 0 | 0 |
Related Allowance, Total | 0 | 0 | 0 |
Average Recorded Investment [Abstract] | ' | ' | ' |
Average Recorded Investment With No Related Allowance Recorded | 0 | 27 | 24 |
Average Recorded Investment With An Allowance Recorded | 0 | 0 | 0 |
Average Recorded Investment, Total | 0 | 27 | 24 |
Interest Income Recognized [Abstract] | ' | ' | ' |
Interest Income Recognized With No Related Allowance Recorded | 0 | 0 | 1 |
Interest Income Recognized With An Allowance Recorded | 0 | 0 | 0 |
Interest Income Recognized, Total | 0 | 0 | 1 |
Interest Income Collected [Abstract] | ' | ' | ' |
Interest Income Collected With No Related Allowance Recorded | 0 | 0 | 1 |
Interest Income Collected With An Allowance Recorded | 0 | 0 | 0 |
Interest Income Collected, Total | 0 | 0 | 1 |
Residential Construction [Member] | ' | ' | ' |
Unpaid Contractual Principal Balance [Abstract] | ' | ' | ' |
Unpaid Contractual Principal Balance With No Related Allowance Recorded | 0 | 0 | 0 |
Unpaid Contractual Principal Balance With An Allowance Recorded | 0 | 0 | 0 |
Unpaid Contractual Principal Balance, Total | 0 | 0 | 0 |
Impaired Balance [Abstract] | ' | ' | ' |
Impaired Balance With No Related Allowance Recorded | 0 | 0 | 0 |
Impaired Balance With An Allowance Recorded | 0 | 0 | 0 |
Impaired Balance, Total | 0 | 0 | 0 |
Related Allowance [Abstract] | ' | ' | ' |
Related Allowance With No Related Allowance Recorded | 0 | 0 | 0 |
Related Allowance With An Allowance Recorded | 0 | 0 | 0 |
Related Allowance, Total | 0 | 0 | 0 |
Average Recorded Investment [Abstract] | ' | ' | ' |
Average Recorded Investment With No Related Allowance Recorded | 0 | 0 | 0 |
Average Recorded Investment With An Allowance Recorded | 0 | 0 | 0 |
Average Recorded Investment, Total | 0 | 0 | 0 |
Interest Income Recognized [Abstract] | ' | ' | ' |
Interest Income Recognized With No Related Allowance Recorded | 0 | 0 | 0 |
Interest Income Recognized With An Allowance Recorded | 0 | 0 | 0 |
Interest Income Recognized, Total | 0 | 0 | 0 |
Interest Income Collected [Abstract] | ' | ' | ' |
Interest Income Collected With No Related Allowance Recorded | 0 | 0 | 0 |
Interest Income Collected With An Allowance Recorded | 0 | 0 | 0 |
Interest Income Collected, Total | $0 | $0 | $0 |