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Loans (Loan Portfolio) (Details) - USD ($) $ in Thousands | Sep. 30, 2018 | Dec. 31, 2017
--- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | $ 2,946,668 | $ 2,694,922
Net Deferred Loan (Fees) Costs | 41,663 | 40,095
Loans, Net | 2,988,331 | 2,735,017
Allowance for loan losses | (33,955) | (34,672)
Total loans, net | 2,954,376 | 2,700,345
Commercial Business [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 537,160 | 449,763
Net Deferred Loan (Fees) Costs | 782 | 563
Loans, Net | 537,942 | 450,326
Commercial Mortgage [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 907,107 | 810,851
Net Deferred Loan (Fees) Costs | (2,096) | (1,943)
Loans, Net | 905,011 | 808,908
Residential Real Estate Loans [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 498,883 | 457,761
Net Deferred Loan (Fees) Costs | 8,715 | 7,522
Loans, Net | 507,598 | 465,283
Residential Real Estate Lines [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 108,227 | 113,422
Net Deferred Loan (Fees) Costs | 2,977 | 2,887
Loans, Net | 111,204 | 116,309
Consumer Indirect [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 878,316 | 845,682
Net Deferred Loan (Fees) Costs | 31,118 | 30,888
Loans, Net | 909,434 | 876,570
Other Consumer [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 16,975 | 17,443
Net Deferred Loan (Fees) Costs | 167 | 178
Loans, Net | $ 17,142 | $ 17,621

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- Definition Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for 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 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.1) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707 + Details
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