Loans and Allowance for Loan Losses (Composition of Loan Portfolio, Excluding Residential Loans Held for Sale) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 3,095,023	$ 3,026,222	$ 2,782,439
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	1,070,374	992,866
Loans	1,070,374	992,866	858,369
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	1,243,397	1,269,533
Loans	1,243,397	1,269,533	1,164,023
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	421,108	381,780
Loans	421,108	381,780	373,400
Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	312,779	327,763
Loans	312,779	327,763	323,378
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	25,772	20,624
Loans	25,772	20,624	18,149
HPFC Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	21,593	33,656
Loans	$ 21,593	$ 33,656	$ 45,120

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. 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=82891408&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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