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Loans (Commercial Loan Portfolio Categorized By Internally Assigned Asset Classification) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment [Line Items]
Total Loans	$ 2,752,450	$ 2,694,922
Commercial Business [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	463,526	449,763
Commercial Business [Member] | Uncriticized [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	441,798	429,692
Commercial Business [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	9,872	7,120
Commercial Business [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	11,856	12,951
Commercial Business [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans
Commercial Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	823,305	810,851
Commercial Mortgage [Member] | Uncriticized [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	804,177	791,127
Commercial Mortgage [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	12,057	12,185
Commercial Mortgage [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans	7,071	7,539
Commercial Mortgage [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Loans

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+ References

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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

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=82891408&loc=d3e4428-111522

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