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Loans and Allowance for Loan Losses - Credit Risk Profile by Internally Assigned Risk Grade (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	$ 1,843,286	$ 1,763,864
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1,759,961	1,733,916
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	73,391	17,340
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	9,934	12,608
Commercial | Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	246,683	230,708
Total loans	246,687	230,739
Commercial | Pass | Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	209,209	219,625
Commercial | Special Mention | Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	37,065	9,957
Commercial | Substandard | Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	409	1,126
Commercial real estate | Commercial real estate, owner-occupied
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	307,683	312,090
Total loans	308,824	313,277
Commercial real estate | Commercial real estate, investor
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	945,484	872,599
Total loans	946,317	873,410
Commercial real estate | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	61,095	76,423
Total loans	61,095	76,423
Commercial real estate | Pass | Commercial real estate, owner-occupied
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	263,625	299,998
Commercial real estate | Pass | Commercial real estate, investor
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	944,924	870,443
Commercial real estate | Pass | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	61,095	73,735
Commercial real estate | Special Mention | Commercial real estate, owner-occupied
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	35,016	4,106
Commercial real estate | Special Mention | Commercial real estate, investor
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	560	2,156
Commercial real estate | Special Mention | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	0	0
Commercial real estate | Substandard | Commercial real estate, owner-occupied
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	9,042	7,986
Commercial real estate | Substandard | Commercial real estate, investor
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	0	0
Commercial real estate | Substandard | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	0	2,688
Residential loans | Home equity
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	115,953	124,613
Total loans	116,024	124,696
Residential loans | Other residential
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	136,657	117,847
Residential loans | Pass | Home equity
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	114,864	122,844
Residential loans | Pass | Other residential
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	136,657	117,847
Residential loans | Special Mention | Home equity
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	750	1,121
Residential loans | Special Mention | Other residential
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	0	0
Residential loans | Substandard | Home equity
Financing Receivable, Credit Quality Indicator [Line Items]
Loans excluding purchased credit-impaired loans	339	648
Residential loans | Substandard | Other residential
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	0	0
Consumer loans | Installment and other consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	27,682	27,472
Consumer loans | Pass | Installment and other consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	27,538	27,312
Consumer loans | Special Mention | Installment and other consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	0	0
Consumer loans | Substandard | Installment and other consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	144	160
Purchased credit-impaired
Financing Receivable, Credit Quality Indicator [Line Items]
Purchased credit-impaired	2,049	2,112
Purchased credit-impaired | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Purchased credit-impaired	2,049	2,112
Purchased credit-impaired | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Purchased credit-impaired	0	0
Purchased credit-impaired | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Purchased credit-impaired	0	0
Purchased credit-impaired | Commercial | Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Purchased credit-impaired	4	31
Purchased credit-impaired | Commercial real estate | Commercial real estate, owner-occupied
Financing Receivable, Credit Quality Indicator [Line Items]
Purchased credit-impaired	1,141	1,187
Purchased credit-impaired | Commercial real estate | Commercial real estate, investor
Financing Receivable, Credit Quality Indicator [Line Items]
Purchased credit-impaired	833	811
Purchased credit-impaired | Commercial real estate | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Purchased credit-impaired	0	0
Purchased credit-impaired | Residential loans | Home equity
Financing Receivable, Credit Quality Indicator [Line Items]
Purchased credit-impaired	71	83
Purchased credit-impaired | Residential loans | Other residential
Financing Receivable, Credit Quality Indicator [Line Items]
Purchased credit-impaired	0	0
Purchased credit-impaired | Consumer loans | Installment and other consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Purchased credit-impaired	$ 0	$ 0

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Loans and Leases Receivable, Net of Deferred Income, Excluding Purchased Credit-impaired Loans

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