Segment and Related Information (Details)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2016
USD ($)
Sep. 30, 2015
USD ($)
Sep. 30, 2016
USD ($)
segment
Sep. 30, 2015
USD ($)
Dec. 31, 2015
USD ($)
[1]
Segment Reporting [Abstract]          
Number of reportable segments | segment     2    
Segment Reporting Information [Line Items]          
Interest income $ 14,063 $ 13,542 $ 42,003 $ 41,218  
Interest expense 1,599 1,481 4,795 4,397  
Noninterest income 3,120 3,055 9,784 9,469  
Income (loss) before income taxes 5,617 5,728 17,351 14,513  
Net income (loss) 3,963 4,037 12,179 10,432  
Depreciation and amortization 673 775 2,198 2,258  
Total assets 1,615,534 1,512,437 1,615,534 1,512,437 $ 1,547,599
Goodwill 43,872 44,333 43,872 44,333 $ 43,872
Capital expenditures 267 602 536 1,203  
Operating Segments [Member] | Community Banking [Member]          
Segment Reporting Information [Line Items]          
Interest income 14,040 13,527 41,950 41,173  
Interest expense 1,376 1,290 4,151 3,834  
Noninterest income 1,967 1,788 6,302 5,809  
Income (loss) before income taxes 5,356 5,160 16,538 13,314  
Net income (loss) 3,760 3,626 11,558 9,522  
Depreciation and amortization 671 772 2,190 2,249  
Total assets 1,611,624 1,510,324 1,611,624 1,510,324  
Goodwill 43,872 44,333 43,872 44,333  
Capital expenditures 267 602 536 1,182  
Operating Segments [Member] | Trust and Investment Services [Member]          
Segment Reporting Information [Line Items]          
Interest income 0 0 0 0  
Interest expense 0 0 0 0  
Noninterest income 1,147 1,262 3,465 3,645  
Income (loss) before income taxes 672 803 2,006 2,026  
Net income (loss) 474 566 1,408 1,456  
Depreciation and amortization 2 3 8 9  
Total assets 0 0 0 0  
Goodwill 0 0 0 0  
Capital expenditures 0 0 0 21  
Other [Member]          
Segment Reporting Information [Line Items]          
Interest income 23 15 53 45  
Interest expense 223 191 644 563  
Noninterest income 6 5 17 15  
Income (loss) before income taxes (411) (235) (1,193) (827)  
Net income (loss) (271) (155) (787) (546)  
Depreciation and amortization 0 0 0 0  
Total assets 231,496 224,120 231,496 224,120  
Goodwill 0 0 0 0  
Capital expenditures 0 0 0 0  
Intersegment Eliminations [Member]          
Segment Reporting Information [Line Items]          
Interest income 0 0 0 0  
Interest expense 0 0 0 0  
Noninterest income 0 0 0 0  
Income (loss) before income taxes 0 0 0 0  
Net income (loss) 0 0 0 0  
Depreciation and amortization 0 0 0 0  
Total assets (227,586) (222,007) (227,586) (222,007)  
Goodwill 0 0 0 0  
Capital expenditures $ 0 $ 0 $ 0 $ 0  
[1] Derived from audited consolidated financial statements.