Loans - Loans Individually Evaluated for Impairment (Detail) (USD $) | 12 Months Ended |
In Thousands, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 |
Financing Receivable, Impaired [Line Items] | ' | ' | ' |
Total with no related allowance recorded, Unpaid Principal Balance | $13,034 | $20,892 | $27,595 |
Total Unpaid Principal Balance | 32,400 | 41,279 | 51,936 |
Total with no related allowance recorded, Recorded Investment | 11,079 | 17,543 | 20,633 |
Total Recorded Investment | 26,071 | 33,555 | 44,849 |
Total with no related allowance recorded, Average Recorded Investment | 12,875 | 21,747 | 16,129 |
Total with no related allowance recorded, Income Recognized | 96 | 1,039 | 355 |
Total with no related allowance recorded, Cash Basis Income Recognized | 106 | 1,115 | 355 |
Total with an allocated allowance recorded, Unpaid Principal Balance | 19,366 | 20,387 | 24,341 |
Total with an allocated allowance recorded, Recorded Investment | 14,992 | 16,012 | 24,216 |
Total with an allocated allowance recorded, Allowance for Loan Losses Allocated | 2,446 | 2,307 | 8,209 |
Total with an allocated allowance recorded, Average Recorded Investment | 17,785 | 23,974 | 39,762 |
Total Average Recorded Investment | 30,660 | 45,721 | 55,891 |
Total with an allocated allowance recorded, Income Recognized | 385 | 692 | 490 |
Total Income Recognized | 481 | 1,731 | 845 |
Total with an allocated allowance recorded, Cash Basis Income Recognized | 402 | 732 | 485 |
Total Cash Basis Income Recognized | 508 | 1,847 | 840 |
Residential Construction [Member] | ' | ' | ' |
Financing Receivable, Impaired [Line Items] | ' | ' | ' |
Total with no related allowance recorded, Unpaid Principal Balance | ' | 3,208 | 8,119 |
Total with no related allowance recorded, Recorded Investment | ' | 1,816 | 4,833 |
Total with no related allowance recorded, Average Recorded Investment | 633 | 2,650 | 4,402 |
Total with no related allowance recorded, Income Recognized | ' | 35 | 199 |
Total with no related allowance recorded, Cash Basis Income Recognized | ' | 35 | 199 |
Total with an allocated allowance recorded, Unpaid Principal Balance | 2,515 | 2,883 | 827 |
Total with an allocated allowance recorded, Recorded Investment | 2,515 | 2,882 | 702 |
Total with an allocated allowance recorded, Allowance for Loan Losses Allocated | 62 | 552 | 35 |
Total with an allocated allowance recorded, Average Recorded Investment | 2,868 | 2,691 | 7,750 |
Total with an allocated allowance recorded, Income Recognized | ' | 55 | 11 |
Total with an allocated allowance recorded, Cash Basis Income Recognized | ' | 67 | 9 |
Other Construction [Member] | ' | ' | ' |
Financing Receivable, Impaired [Line Items] | ' | ' | ' |
Total with no related allowance recorded, Unpaid Principal Balance | 6,564 | 11,604 | 10,391 |
Total with no related allowance recorded, Recorded Investment | 6,564 | 9,649 | 7,127 |
Total with no related allowance recorded, Average Recorded Investment | 7,507 | 9,334 | 4,465 |
Total with no related allowance recorded, Income Recognized | 1 | 4 | 22 |
Total with no related allowance recorded, Cash Basis Income Recognized | 1 | 8 | 22 |
Total with an allocated allowance recorded, Unpaid Principal Balance | 2,291 | 1,011 | 4,233 |
Total with an allocated allowance recorded, Recorded Investment | 2,291 | 1,011 | 4,233 |
Total with an allocated allowance recorded, Allowance for Loan Losses Allocated | 414 | 399 | 1,843 |
Total with an allocated allowance recorded, Average Recorded Investment | 2,866 | 3,883 | 9,415 |
Total with an allocated allowance recorded, Income Recognized | 15 | 42 | 8 |
Total with an allocated allowance recorded, Cash Basis Income Recognized | 15 | 43 | 8 |
Revolving, Open Ended [Member] | ' | ' | ' |
Financing Receivable, Impaired [Line Items] | ' | ' | ' |
Total with no related allowance recorded, Unpaid Principal Balance | 110 | ' | ' |
Total with no related allowance recorded, Recorded Investment | 110 | ' | ' |
Total with no related allowance recorded, Average Recorded Investment | 184 | ' | 345 |
Total with no related allowance recorded, Income Recognized | 4 | ' | ' |
Total with no related allowance recorded, Cash Basis Income Recognized | 5 | ' | ' |
Total with an allocated allowance recorded, Unpaid Principal Balance | 179 | 575 | 20 |
Total with an allocated allowance recorded, Recorded Investment | 179 | 575 | 20 |
Total with an allocated allowance recorded, Allowance for Loan Losses Allocated | 132 | 121 | 20 |
Total with an allocated allowance recorded, Average Recorded Investment | 377 | 608 | 637 |
Total with an allocated allowance recorded, Income Recognized | 3 | -2 | ' |
Total with an allocated allowance recorded, Cash Basis Income Recognized | 5 | 3 | ' |
First Liens [Member] | ' | ' | ' |
Financing Receivable, Impaired [Line Items] | ' | ' | ' |
Total with no related allowance recorded, Unpaid Principal Balance | 1,163 | 2,446 | 6,811 |
Total with no related allowance recorded, Recorded Investment | 1,163 | 2,444 | 6,650 |
Total with no related allowance recorded, Average Recorded Investment | 1,751 | 3,943 | 3,470 |
Total with no related allowance recorded, Income Recognized | 29 | 81 | 125 |
Total with no related allowance recorded, Cash Basis Income Recognized | 33 | 80 | 125 |
Total with an allocated allowance recorded, Unpaid Principal Balance | 6,122 | 3,333 | 3,005 |
Total with an allocated allowance recorded, Recorded Investment | 6,122 | 3,333 | 3,005 |
Total with an allocated allowance recorded, Allowance for Loan Losses Allocated | 460 | 288 | 617 |
Total with an allocated allowance recorded, Average Recorded Investment | 5,167 | 3,118 | 8,927 |
Total with an allocated allowance recorded, Income Recognized | 272 | 157 | 119 |
Total with an allocated allowance recorded, Cash Basis Income Recognized | 255 | 184 | 119 |
Junior Liens [Member] | ' | ' | ' |
Financing Receivable, Impaired [Line Items] | ' | ' | ' |
Total with no related allowance recorded, Unpaid Principal Balance | 83 | 74 | ' |
Total with no related allowance recorded, Recorded Investment | 83 | 74 | ' |
Total with no related allowance recorded, Average Recorded Investment | 70 | 15 | 107 |
Total with no related allowance recorded, Income Recognized | 4 | 47 | ' |
Total with no related allowance recorded, Cash Basis Income Recognized | 3 | 47 | ' |
Total with an allocated allowance recorded, Unpaid Principal Balance | ' | 263 | 427 |
Total with an allocated allowance recorded, Recorded Investment | ' | 263 | 427 |
Total with an allocated allowance recorded, Allowance for Loan Losses Allocated | ' | 184 | 150 |
Total with an allocated allowance recorded, Average Recorded Investment | 87 | 213 | 345 |
Total with an allocated allowance recorded, Income Recognized | ' | 16 | 7 |
Total with an allocated allowance recorded, Cash Basis Income Recognized | ' | 16 | 7 |
Farmland [Member] | ' | ' | ' |
Financing Receivable, Impaired [Line Items] | ' | ' | ' |
Total with no related allowance recorded, Unpaid Principal Balance | ' | ' | 485 |
Total with no related allowance recorded, Recorded Investment | ' | ' | 234 |
Total with no related allowance recorded, Allowance for Loan Losses Allocated | ' | ' | ' |
Total with no related allowance recorded, Average Recorded Investment | ' | 187 | 47 |
Total with no related allowance recorded, Income Recognized | ' | ' | ' |
Total with no related allowance recorded, Cash Basis Income Recognized | ' | ' | ' |
Total with an allocated allowance recorded, Unpaid Principal Balance | ' | ' | ' |
Total with an allocated allowance recorded, Recorded Investment | ' | ' | ' |
Total with an allocated allowance recorded, Allowance for Loan Losses Allocated | ' | ' | ' |
Total with an allocated allowance recorded, Average Recorded Investment | ' | ' | 469 |
Total with an allocated allowance recorded, Income Recognized | ' | ' | ' |
Total with an allocated allowance recorded, Cash Basis Income Recognized | ' | ' | ' |
Owner Occupied [Member] | ' | ' | ' |
Financing Receivable, Impaired [Line Items] | ' | ' | ' |
Total with no related allowance recorded, Unpaid Principal Balance | 1,411 | 1,097 | ' |
Total with no related allowance recorded, Recorded Investment | 1,411 | 1,097 | ' |
Total with no related allowance recorded, Average Recorded Investment | 1,159 | 1,017 | 1,772 |
Total with no related allowance recorded, Income Recognized | 58 | 50 | ' |
Total with no related allowance recorded, Cash Basis Income Recognized | 64 | 48 | ' |
Total with an allocated allowance recorded, Unpaid Principal Balance | 1,845 | 1,722 | 1,285 |
Total with an allocated allowance recorded, Recorded Investment | 1,845 | 1,722 | 1,285 |
Total with an allocated allowance recorded, Allowance for Loan Losses Allocated | 276 | 287 | 569 |
Total with an allocated allowance recorded, Average Recorded Investment | 1,862 | 1,105 | 2,141 |
Total with an allocated allowance recorded, Income Recognized | 129 | 149 | 34 |
Total with an allocated allowance recorded, Cash Basis Income Recognized | 126 | 143 | 34 |
Non-Owner Occupied [Member] | ' | ' | ' |
Financing Receivable, Impaired [Line Items] | ' | ' | ' |
Total with no related allowance recorded, Unpaid Principal Balance | 3,582 | 1,992 | 181 |
Total with no related allowance recorded, Recorded Investment | 1,627 | 1,992 | 181 |
Total with no related allowance recorded, Average Recorded Investment | 1,354 | 3,519 | 872 |
Total with no related allowance recorded, Income Recognized | ' | 766 | 9 |
Total with no related allowance recorded, Cash Basis Income Recognized | ' | 835 | 9 |
Total with an allocated allowance recorded, Unpaid Principal Balance | ' | 2,132 | 5,777 |
Total with an allocated allowance recorded, Recorded Investment | ' | 2,132 | 5,777 |
Total with an allocated allowance recorded, Allowance for Loan Losses Allocated | ' | 30 | 1,408 |
Total with an allocated allowance recorded, Average Recorded Investment | 1,224 | 6,130 | 3,819 |
Total with an allocated allowance recorded, Income Recognized | ' | 131 | 206 |
Total with an allocated allowance recorded, Cash Basis Income Recognized | ' | 132 | 206 |
Other Real Estate Loans [Member] | ' | ' | ' |
Financing Receivable, Impaired [Line Items] | ' | ' | ' |
Total with no related allowance recorded, Unpaid Principal Balance | 119 | 126 | ' |
Total with no related allowance recorded, Recorded Investment | 119 | 126 | ' |
Total with no related allowance recorded, Average Recorded Investment | 123 | 32 | ' |
Total with no related allowance recorded, Income Recognized | ' | 30 | ' |
Total with no related allowance recorded, Cash Basis Income Recognized | ' | 37 | ' |
Total with an allocated allowance recorded, Unpaid Principal Balance | ' | 2,204 | 2,229 |
Total with an allocated allowance recorded, Recorded Investment | ' | 2,204 | 2,229 |
Total with an allocated allowance recorded, Allowance for Loan Losses Allocated | ' | 70 | 73 |
Total with an allocated allowance recorded, Average Recorded Investment | 1,100 | 2,217 | 1,464 |
Total with an allocated allowance recorded, Income Recognized | ' | 143 | 88 |
Total with an allocated allowance recorded, Cash Basis Income Recognized | ' | 143 | 85 |
Commercial and Industrial [Member] | ' | ' | ' |
Financing Receivable, Impaired [Line Items] | ' | ' | ' |
Total with no related allowance recorded, Unpaid Principal Balance | ' | 345 | 141 |
Total with no related allowance recorded, Recorded Investment | ' | 345 | 141 |
Total with no related allowance recorded, Average Recorded Investment | 1 | 125 | 296 |
Total with no related allowance recorded, Income Recognized | ' | 26 | ' |
Total with no related allowance recorded, Cash Basis Income Recognized | ' | 25 | ' |
Total with an allocated allowance recorded, Unpaid Principal Balance | 176 | 37 | 141 |
Total with an allocated allowance recorded, Recorded Investment | 176 | 37 | 141 |
Total with an allocated allowance recorded, Allowance for Loan Losses Allocated | 176 | 12 | 87 |
Total with an allocated allowance recorded, Average Recorded Investment | 374 | 172 | 228 |
Total with an allocated allowance recorded, Income Recognized | -35 | 1 | 7 |
Total with an allocated allowance recorded, Cash Basis Income Recognized | ' | 1 | 7 |
Consumer [Member] | ' | ' | ' |
Financing Receivable, Impaired [Line Items] | ' | ' | ' |
Total with no related allowance recorded, Unpaid Principal Balance | 1 | ' | ' |
Total with no related allowance recorded, Recorded Investment | 1 | ' | ' |
Total with no related allowance recorded, Average Recorded Investment | ' | 11 | 60 |
Total with an allocated allowance recorded, Unpaid Principal Balance | 11 | ' | 168 |
Total with an allocated allowance recorded, Recorded Investment | 11 | ' | 168 |
Total with an allocated allowance recorded, Allowance for Loan Losses Allocated | ' | ' | 72 |
Total with an allocated allowance recorded, Average Recorded Investment | 7 | 62 | 42 |
Total with an allocated allowance recorded, Income Recognized | 1 | ' | 10 |
Total with an allocated allowance recorded, Cash Basis Income Recognized | 1 | ' | 10 |
Other Loans [Member] | ' | ' | ' |
Financing Receivable, Impaired [Line Items] | ' | ' | ' |
Total with no related allowance recorded, Unpaid Principal Balance | ' | ' | 1,467 |
Total with no related allowance recorded, Recorded Investment | ' | ' | 1,467 |
Total with no related allowance recorded, Allowance for Loan Losses Allocated | ' | ' | ' |
Total with no related allowance recorded, Average Recorded Investment | ' | 914 | 293 |
Total with no related allowance recorded, Income Recognized | ' | ' | ' |
Total with no related allowance recorded, Cash Basis Income Recognized | ' | ' | ' |
Total with an allocated allowance recorded, Unpaid Principal Balance | 6,227 | 6,227 | 6,229 |
Total with an allocated allowance recorded, Recorded Investment | 1,853 | 1,853 | 6,229 |
Total with an allocated allowance recorded, Allowance for Loan Losses Allocated | 926 | 364 | 3,335 |
Total with an allocated allowance recorded, Average Recorded Investment | 1,853 | 3,775 | 4,525 |
Agricultural [Member] | ' | ' | ' |
Financing Receivable, Impaired [Line Items] | ' | ' | ' |
Total with no related allowance recorded, Unpaid Principal Balance | 1 | ' | ' |
Total with no related allowance recorded, Recorded Investment | 1 | ' | ' |
Total with no related allowance recorded, Average Recorded Investment | $93 | ' | ' |