Loans - Impaired Loan Balances By Portfolio Segment (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |
Mar. 31, 2016 | Dec. 31, 2015 |
Recorded Investment [Abstract] | | |
Impaired loan, with no related allowance, recorded investment | $ 1,027 | $ 1,724 |
Impaired loan, with an related allowance, recorded investment | 3,274 | 2,983 |
Impaired loan, total, recorded investment | 4,301 | 4,707 |
Unpaid Principal Balance [Abstract] | | |
Impaired loan, with no related allowance, unpaid principal balance | 1,027 | 1,725 |
Impaired loan, with an related allowance, unpaid principal balance | 3,995 | 3,026 |
Impaired loan, total, unpaid principal balance | 5,022 | 4,751 |
Impaired loan, total, related allowance | 32 | 35 |
Average Recorded Investment [Abstract] | | |
Impaired loan, with no related allowance, average recorded investment | 1,043 | 2,216 |
Impaired loan, with related allowance, average recorded investment | 3,073 | 2,387 |
Impaired loan, total, average recorded investment | 4,116 | 4,603 |
Interest Income Recognized [Abstract] | | |
Impaired loan, with no related allowance, interest income recognized | 14 | 1 |
Impaired loan, with related allowance, interest income recognized | 15 | 65 |
Impaired loan, total, interest income recognized | 29 | 66 |
Commercial [Member] | | |
Recorded Investment [Abstract] | | |
Impaired loan, with no related allowance, recorded investment | 3 | 4 |
Impaired loan, with an related allowance, recorded investment | 118 | 91 |
Impaired loan, total, recorded investment | 121 | 95 |
Unpaid Principal Balance [Abstract] | | |
Impaired loan, with no related allowance, unpaid principal balance | 3 | 4 |
Impaired loan, with an related allowance, unpaid principal balance | 118 | 91 |
Impaired loan, total, unpaid principal balance | 121 | 95 |
Impaired loan, total, related allowance | 0 | 0 |
Average Recorded Investment [Abstract] | | |
Impaired loan, with no related allowance, average recorded investment | 3 | 47 |
Impaired loan, with related allowance, average recorded investment | 104 | 99 |
Impaired loan, total, average recorded investment | 107 | 146 |
Interest Income Recognized [Abstract] | | |
Impaired loan, with no related allowance, interest income recognized | 0 | 0 |
Impaired loan, with related allowance, interest income recognized | 4 | 0 |
Impaired loan, total, interest income recognized | 4 | 0 |
Commercial real estate [Member] | Construction and land development [Member] | | |
Recorded Investment [Abstract] | | |
Impaired loan, with no related allowance, recorded investment | 0 | 205 |
Impaired loan, with an related allowance, recorded investment | 490 | 448 |
Impaired loan, total, recorded investment | 490 | 653 |
Unpaid Principal Balance [Abstract] | | |
Impaired loan, with no related allowance, unpaid principal balance | 0 | 205 |
Impaired loan, with an related allowance, unpaid principal balance | 491 | 449 |
Impaired loan, total, unpaid principal balance | 491 | 654 |
Impaired loan, total, related allowance | 5 | 6 |
Average Recorded Investment [Abstract] | | |
Impaired loan, with no related allowance, average recorded investment | 0 | 220 |
Impaired loan, with related allowance, average recorded investment | 469 | 563 |
Impaired loan, total, average recorded investment | 469 | 783 |
Interest Income Recognized [Abstract] | | |
Impaired loan, with no related allowance, interest income recognized | 0 | 0 |
Impaired loan, with related allowance, interest income recognized | 6 | 26 |
Impaired loan, total, interest income recognized | 6 | 26 |
Commercial real estate [Member] | Real estate [Member] | | |
Recorded Investment [Abstract] | | |
Impaired loan, with no related allowance, recorded investment | 843 | 1,202 |
Impaired loan, with an related allowance, recorded investment | 464 | 390 |
Impaired loan, total, recorded investment | 1,307 | 1,592 |
Unpaid Principal Balance [Abstract] | | |
Impaired loan, with no related allowance, unpaid principal balance | 843 | 1,206 |
Impaired loan, with an related allowance, unpaid principal balance | 465 | 391 |
Impaired loan, total, unpaid principal balance | 1,308 | 1,597 |
Impaired loan, total, related allowance | 4 | 3 |
Average Recorded Investment [Abstract] | | |
Impaired loan, with no related allowance, average recorded investment | 856 | 1,504 |
Impaired loan, with related allowance, average recorded investment | 427 | 353 |
Impaired loan, total, average recorded investment | 1,283 | 1,857 |
Interest Income Recognized [Abstract] | | |
Impaired loan, with no related allowance, interest income recognized | 12 | 1 |
Impaired loan, with related allowance, interest income recognized | 0 | 17 |
Impaired loan, total, interest income recognized | 12 | 18 |
Residential [Member] | Real estate [Member] | | |
Recorded Investment [Abstract] | | |
Impaired loan, with no related allowance, recorded investment | 0 | 127 |
Impaired loan, with an related allowance, recorded investment | 1,811 | 1,649 |
Impaired loan, total, recorded investment | 1,811 | 1,776 |
Unpaid Principal Balance [Abstract] | | |
Impaired loan, with no related allowance, unpaid principal balance | 0 | 124 |
Impaired loan, with an related allowance, unpaid principal balance | 1,971 | 1,690 |
Impaired loan, total, unpaid principal balance | 1,971 | 1,814 |
Impaired loan, total, related allowance | 23 | 0 |
Average Recorded Investment [Abstract] | | |
Impaired loan, with no related allowance, average recorded investment | 0 | 126 |
Impaired loan, with related allowance, average recorded investment | 1,675 | 1,034 |
Impaired loan, total, average recorded investment | 1,675 | 1,160 |
Interest Income Recognized [Abstract] | | |
Impaired loan, with no related allowance, interest income recognized | 0 | 0 |
Impaired loan, with related allowance, interest income recognized | 4 | 22 |
Impaired loan, total, interest income recognized | 4 | 22 |
Residential [Member] | Home equity [Member] | | |
Recorded Investment [Abstract] | | |
Impaired loan, with no related allowance, recorded investment | 170 | 173 |
Impaired loan, with an related allowance, recorded investment | 356 | 397 |
Impaired loan, total, recorded investment | 526 | 570 |
Unpaid Principal Balance [Abstract] | | |
Impaired loan, with no related allowance, unpaid principal balance | 170 | 173 |
Impaired loan, with an related allowance, unpaid principal balance | 767 | 396 |
Impaired loan, total, unpaid principal balance | 937 | 569 |
Impaired loan, total, related allowance | 0 | 25 |
Average Recorded Investment [Abstract] | | |
Impaired loan, with no related allowance, average recorded investment | 172 | 305 |
Impaired loan, with related allowance, average recorded investment | 377 | 327 |
Impaired loan, total, average recorded investment | 549 | 632 |
Interest Income Recognized [Abstract] | | |
Impaired loan, with no related allowance, interest income recognized | 2 | 0 |
Impaired loan, with related allowance, interest income recognized | 1 | 0 |
Impaired loan, total, interest income recognized | 3 | 0 |
Consumer [Member] | | |
Recorded Investment [Abstract] | | |
Impaired loan, with no related allowance, recorded investment | 11 | 13 |
Impaired loan, with an related allowance, recorded investment | 35 | 8 |
Impaired loan, total, recorded investment | 46 | 21 |
Unpaid Principal Balance [Abstract] | | |
Impaired loan, with no related allowance, unpaid principal balance | 11 | 13 |
Impaired loan, with an related allowance, unpaid principal balance | 183 | 9 |
Impaired loan, total, unpaid principal balance | 194 | 22 |
Impaired loan, total, related allowance | 0 | 1 |
Average Recorded Investment [Abstract] | | |
Impaired loan, with no related allowance, average recorded investment | 12 | 14 |
Impaired loan, with related allowance, average recorded investment | 21 | 11 |
Impaired loan, total, average recorded investment | 33 | 25 |
Interest Income Recognized [Abstract] | | |
Impaired loan, with no related allowance, interest income recognized | 0 | 0 |
Impaired loan, with related allowance, interest income recognized | 0 | 0 |
Impaired loan, total, interest income recognized | $ 0 | $ 0 |