Allowance For Loan Losses - Evaluation Method (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Schedule of Financing Receivable by Evaluation Method [Line Items]
Loans individually evaluated for impairment	$ 28,009	$ 31,878
Loans collectively evaluated for impairment	2,659,219	2,536,684
Gross loans	2,687,228	2,568,562
Commercial real estate
Schedule of Financing Receivable by Evaluation Method [Line Items]
Loans individually evaluated for impairment	14,166	17,515
Loans collectively evaluated for impairment	1,427,984	1,376,664
Gross loans	1,442,150	1,394,179
Commercial and industrial
Schedule of Financing Receivable by Evaluation Method [Line Items]
Loans individually evaluated for impairment	6,901	9,332
Loans collectively evaluated for impairment	530,889	491,895
Gross loans	537,790	501,227
Commercial construction
Schedule of Financing Receivable by Evaluation Method [Line Items]
Loans individually evaluated for impairment	5,304	3,347
Loans collectively evaluated for impairment	340,379	314,130
Gross loans	345,683	317,477
Residential mortgages
Schedule of Financing Receivable by Evaluation Method [Line Items]
Loans individually evaluated for impairment	1,206	1,229
Loans collectively evaluated for impairment	252,982	246,144
Gross loans	254,188	247,373
Home equity
Schedule of Financing Receivable by Evaluation Method [Line Items]
Loans individually evaluated for impairment	394	411
Loans collectively evaluated for impairment	96,829	97,841
Gross loans	97,223	98,252
Consumer
Schedule of Financing Receivable by Evaluation Method [Line Items]
Loans individually evaluated for impairment	38	44
Loans collectively evaluated for impairment	10,156	10,010
Gross loans	$ 10,194	$ 10,054

[Line Items] for Schedule of loans by evaluation method used for assessing the allowance for loan loss.

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The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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The balance of financing receivables that were individually evaluated for impairment.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

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