Allowance For Loan Losses - Adversely Classified Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	$ 3,194,723	$ 2,568,562
Adversely classified loans to total loans	1.29%	1.45%
Commercial real estate
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	$ 1,471,586	$ 1,394,179
Commercial and industrial
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	454,455	501,227
Commercial construction
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	404,008	317,477
SBA Paycheck Protection Program
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	505,557	0
Residential mortgages
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	261,786	247,373
Home equity
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	88,157	98,252
Consumer
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	9,174	10,054
Substandard
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	38,581	34,749
Substandard | Commercial real estate
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	18,311	16,664
Substandard | Commercial and industrial
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	9,872	10,900
Substandard | Commercial construction
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	8,798	4,836
Substandard | SBA Paycheck Protection Program
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	0
Substandard | Residential mortgages
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	983	1,825
Substandard | Home equity
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	556	455
Substandard | Consumer
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	61	69
Doubtful
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	2,452	2,373
Doubtful | Commercial real estate
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	0	0
Doubtful | Commercial and industrial
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	2,452	2,370
Doubtful | Commercial construction
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	0	0
Doubtful | SBA Paycheck Protection Program
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	0
Doubtful | Residential mortgages
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	0	0
Doubtful | Home equity
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	0	0
Doubtful | Consumer
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	0	3
Loss
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	0	0
Loss | Commercial real estate
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	0	0
Loss | Commercial and industrial
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	0	0
Loss | Commercial construction
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	0	0
Loss | SBA Paycheck Protection Program
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	0
Loss | Residential mortgages
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	0	0
Loss | Home equity
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	0	0
Loss | Consumer
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	0	0
Not Adversely Classified
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	3,153,690	2,531,440
Not Adversely Classified | Commercial real estate
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	1,453,275	1,377,515
Not Adversely Classified | Commercial and industrial
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	442,131	487,957
Not Adversely Classified | Commercial construction
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	395,210	312,641
Not Adversely Classified | SBA Paycheck Protection Program
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	505,557
Not Adversely Classified | Residential mortgages
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	260,803	245,548
Not Adversely Classified | Home equity
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	87,601	97,797
Not Adversely Classified | Consumer
Financing Receivable, Credit Quality Indicators [Line Items]
Gross loans	$ 9,113	$ 9,982