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Loans (Loan Portfolio) (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | $ 3,114,733 | $ 3,044,320
Net Deferred Loan (Fees) Costs | 41,687 | 42,278
Loans, Net | 3,156,420 | 3,086,598
Allowance for loan losses | (31,668) | (33,914)
Total loans, net | 3,124,752 | 3,052,684
Commercial Business [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 573,610 | 557,040
Net Deferred Loan (Fees) Costs | 845 | 821
Loans, Net | 574,455 | 557,861
Commercial Mortgage [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 1,037,304 | 960,265
Net Deferred Loan (Fees) Costs | (1,854) | (2,071)
Loans, Net | 1,035,450 | 958,194
Residential Real Estate Loans [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 547,839 | 514,981
Net Deferred Loan (Fees) Costs | 10,817 | 9,174
Loans, Net | 558,656 | 524,155
Residential Real Estate Lines [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 104,545 | 106,712
Net Deferred Loan (Fees) Costs | 3,070 | 3,006
Loans, Net | 107,615 | 109,718
Consumer Indirect [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 834,968 | 888,732
Net Deferred Loan (Fees) Costs | 28,646 | 31,185
Loans, Net | 863,614 | 919,917
Other Consumer [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Principal Amount Outstanding | 16,467 | 16,590
Net Deferred Loan (Fees) Costs | 163 | 163
Loans, Net | $ 16,630 | $ 16,753

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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=118936363&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=118939070&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=118936363&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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