Loans - Schedule of Loan Assigned Risk Rating within 12 Months of Balance Sheet Date (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	$ 2,729,295	$ 2,454,853
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	1,767,976	1,575,166
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	28,950	13,720
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	25,679	25,187
Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	0	0
Pass, Special Mention, Substandard, Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	1,822,605	1,614,073
Commercial, industrial, and agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	1,033,631	916,297
Commercial, industrial, and agricultural | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	997,103	890,360
Commercial, industrial, and agricultural | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	19,197	10,484
Commercial, industrial, and agricultural | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	17,331	15,453
Commercial, industrial, and agricultural | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	0	0
Commercial mortgages
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	788,974	697,776
Commercial mortgages | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	770,873	684,806
Commercial mortgages | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	9,753	3,236
Commercial mortgages | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	8,348	9,734
Commercial mortgages | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Net loans	$ 0	$ 0