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Loans and Allowance for Loan Losses - Credit Risk Profile by Internally Assigned Risk Grade (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans | $ 1,763,864 | $ 1,679,013
Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans | 1,733,916 | 1,629,865
Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans | 17,340 | 21,242
Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans | 12,608 | 27,906
Commercial | Commercial and industrial |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 230,708 | 235,770
Total loans | 230,739 | 235,835
Commercial | Pass | Commercial and industrial |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 219,625 | 214,636
Commercial | Special Mention | Commercial and industrial |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 9,957 | 9,318
Commercial | Substandard | Commercial and industrial |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 1,126 | 11,816
Commercial real estate | Commercial real estate, owner-occupied |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 312,090 | 299,797
Total loans | 313,277 | 300,963
Commercial real estate | Commercial real estate, investor |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 872,599 | 822,194
Total loans | 873,410 | 822,984
Commercial real estate | Construction |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 76,423 | 63,828
Total loans | 76,423 | 63,828
Commercial real estate | Pass | Commercial real estate, owner-occupied |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 299,998 | 281,104
Commercial real estate | Pass | Commercial real estate, investor |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 870,443 | 818,570
Commercial real estate | Pass | Construction |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 73,735 | 60,859
Commercial real estate | Special Mention | Commercial real estate, owner-occupied |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 4,106 | 9,284
Commercial real estate | Special Mention | Commercial real estate, investor |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 2,156 | 1,850
Commercial real estate | Special Mention | Construction |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 0 | 0
Commercial real estate | Substandard | Commercial real estate, owner-occupied |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 7,986 | 9,409
Commercial real estate | Substandard | Commercial real estate, investor |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 0 | 1,774
Commercial real estate | Substandard | Construction |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 2,688 | 2,969
Residential loans | Home equity |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 124,613 | 132,373
Total loans | 124,696 | 132,467
Residential loans | Other residential |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans | 117,847 | 95,526
Residential loans | Pass | Home equity |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 122,844 | 130,558
Residential loans | Pass | Other residential |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans | 117,847 | 95,526
Residential loans | Special Mention | Home equity |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 1,121 | 0
Residential loans | Special Mention | Other residential |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans | 0 | 0
Residential loans | Substandard | Home equity |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans excluding purchased credit-impaired loans | 648 | 1,815
Residential loans | Substandard | Other residential |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans | 0 | 0
Consumer loans | Installment and other consumer |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans | 27,472 | 27,410
Consumer loans | Pass | Installment and other consumer |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans | 27,312 | 27,287
Consumer loans | Special Mention | Installment and other consumer |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans | 0 | 0
Consumer loans | Substandard | Installment and other consumer |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans | 160 | 123
Purchased credit-impaired |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Purchased credit-impaired | 2,112 | 2,115
Purchased credit-impaired | Pass |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Purchased credit-impaired | 2,112 | 1,325
Purchased credit-impaired | Special Mention |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Purchased credit-impaired | 0 | 790
Purchased credit-impaired | Substandard |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Purchased credit-impaired | 0 | 0
Purchased credit-impaired | Commercial | Commercial and industrial |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Purchased credit-impaired | 31 | 65
Purchased credit-impaired | Commercial real estate | Commercial real estate, owner-occupied |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Purchased credit-impaired | 1,187 | 1,166
Purchased credit-impaired | Commercial real estate | Commercial real estate, investor |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Purchased credit-impaired | 811 | 790
Purchased credit-impaired | Commercial real estate | Construction |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Purchased credit-impaired | 0 | 0
Purchased credit-impaired | Residential loans | Home equity |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Purchased credit-impaired | 83 | 94
Purchased credit-impaired | Residential loans | Other residential |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Purchased credit-impaired | 0 | 0
Purchased credit-impaired | Consumer loans | Installment and other consumer |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Purchased credit-impaired | $ 0 | $ 0

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