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Allowance for Loan Losses and Credit Quality of Loans, Credit Quality by Loan Class (Details) - USD ($) $ in Thousands | Jun. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Originated Loans [Member] | Commercial Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | $ 1,846,609 | $ 1,741,936
Originated Loans [Member] | Commercial Loans [Member] | Pass [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 1,736,721 | 1,648,664
Originated Loans [Member] | Commercial Loans [Member] | Special Mention [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 38,626 | 23,680
Originated Loans [Member] | Commercial Loans [Member] | Substandard [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 71,254 | 69,584
Originated Loans [Member] | Commercial Loans [Member] | Doubtful [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 8 | 8
Originated Loans [Member] | Business Banking Credit Exposure [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 399,563 | 398,435
Originated Loans [Member] | Business Banking Credit Exposure [Member] | Non-classified [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 383,016 | 379,445
Originated Loans [Member] | Business Banking Credit Exposure [Member] | Classified [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 16,547 | 18,990
Originated Loans [Member] | Consumer Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 1,931,224 | 1,858,724
Originated Loans [Member] | Consumer Loans [Member] | Performing [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 1,922,702 | 1,847,216
Originated Loans [Member] | Consumer Loans [Member] | Nonperforming [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 8,522 | 11,508
Originated Loans [Member] | Residential Mortgage Credit Exposure [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 902,007 | 848,842
Originated Loans [Member] | Residential Mortgage Credit Exposure [Member] | Performing [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 894,247 | 838,816
Originated Loans [Member] | Residential Mortgage Credit Exposure [Member] | Nonperforming [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 7,760 | 10,026
Originated Loans [Member] | Residential Mortgage Credit Exposure [Member] | Residential Mortgage [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 902,007 | 848,842
Originated Loans [Member] | Residential Mortgage Credit Exposure [Member] | Residential Mortgage [Member] | Performing [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 894,247 | 838,816
Originated Loans [Member] | Residential Mortgage Credit Exposure [Member] | Residential Mortgage [Member] | Nonperforming [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 7,760 | 10,026
Acquired Loans [Member] | Commercial Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 267,500 | 275,152
Acquired Loans [Member] | Commercial Loans [Member] | Pass [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 243,041 | 249,666
Acquired Loans [Member] | Commercial Loans [Member] | Special Mention [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 6,989 | 5,486
Acquired Loans [Member] | Commercial Loans [Member] | Substandard [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 17,470 | 20,000
Acquired Loans [Member] | Business Banking Credit Exposure [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 51,918 | 58,179
Acquired Loans [Member] | Business Banking Credit Exposure [Member] | Non-classified [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 47,546 | 53,264
Acquired Loans [Member] | Business Banking Credit Exposure [Member] | Classified [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 4,372 | 4,915
Acquired Loans [Member] | Consumer Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 120,316 | 147,256
Acquired Loans [Member] | Consumer Loans [Member] | Performing [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 119,525 | 146,494
Acquired Loans [Member] | Consumer Loans [Member] | Nonperforming [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 791 | 762
Acquired Loans [Member] | Residential Mortgage Credit Exposure [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 251,751 | 266,747
Acquired Loans [Member] | Residential Mortgage Credit Exposure [Member] | Performing [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 248,624 | 262,883
Acquired Loans [Member] | Residential Mortgage Credit Exposure [Member] | Nonperforming [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 3,127 | 3,864
Acquired Loans [Member] | Residential Mortgage Credit Exposure [Member] | Residential Mortgage [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 251,751 | 266,747
Acquired Loans [Member] | Residential Mortgage Credit Exposure [Member] | Residential Mortgage [Member] | Performing [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | 248,624 | 262,883
Acquired Loans [Member] | Residential Mortgage Credit Exposure [Member] | Residential Mortgage [Member] | Nonperforming [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Financing Receivable | $ 3,127 | $ 3,864

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- Definition Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 3 -Article 5 + Details
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