Loans and Allowance for Loan Losses (Composition of Loan Portfolio, Excluding Residential Loans Held for Sale) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans:	$ 2,782,439	$ 2,594,564	$ 2,490,206
Residential real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	858,369	802,494
Loans:	858,369	802,494	820,617
Commercial real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	1,164,023	1,050,780
Loans:	1,164,023	1,050,780	927,951
Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	373,400	333,639
Loans:	373,400	333,639	297,721
Home equity loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	323,378	329,907
Loans:	323,378	329,907	348,634
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	18,149	17,332
Loans:	18,149	17,332	17,953
HPFC Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	45,120	60,412
Loans:	$ 45,120	$ 60,412	$ 77,330

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5074-111524

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