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Loans (Changes in the Allowance for Credit Losses) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | $ 30,482 | $ 33,914 | $ 34,672
Allowance for loan losses, Charge-offs | (21,625) | (17,811) | (15,734)
Allowance for loan losses, Recoveries | 7,810 | 6,335 | 6,042
Allowance for loan losses, Provision (credit) | 26,159 | 8,044 | 8,934
Allowance for loan losses, Ending balance | 52,420 | 30,482 | 33,914
Allowance for loan losses, Individually Evaluated for impairment |  | 693 | 206
Allowance for loan losses, Collectively Evaluated for impairment |  | 29,789 | 33,708
Allowance for loan losses, Individually Evaluated for impairment |  | 4,323 | 3,078
Allowance for loan losses, Collectively Evaluated for impairment |  | 3,175,142 | 3,041,242
Loans, Ending balance | 3,557,908 | 3,179,465 | 3,044,320
Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 9,594 |  |
Allowance for loan losses, Ending balance |  | 9,594 |
Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 40,076 |  |
Allowance for loan losses, Ending balance |  | 40,076 |
Commercial Business [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 11,358 | 14,312 | 15,668
Allowance for loan losses, Charge-offs | (9,093) | (2,481) | (2,319)
Allowance for loan losses, Recoveries | 1,709 | 492 | 509
Allowance for loan losses, Provision (credit) | 9,852 | (965) | 454
Allowance for loan losses, Ending balance | 13,580 | 11,358 | 14,312
Allowance for loan losses, Individually Evaluated for impairment |  | 214 | 205
Allowance for loan losses, Collectively Evaluated for impairment |  | 11,144 | 14,107
Allowance for loan losses, Individually Evaluated for impairment |  | 1,177 | 1,044
Allowance for loan losses, Collectively Evaluated for impairment |  | 570,045 | 555,996
Loans, Ending balance | 798,409 | 571,222 | 557,040
Commercial Business [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | (246) |  |
Allowance for loan losses, Ending balance |  | (246) |
Commercial Business [Member] | Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 11,112 |  |
Allowance for loan losses, Ending balance |  | 11,112 |
Commercial Mortgage [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 5,681 | 5,219 | 3,696
Allowance for loan losses, Charge-offs | (1,792) | (2,997) | (1,020)
Allowance for loan losses, Recoveries | 37 | 17 | 13
Allowance for loan losses, Provision (credit) | 10,527 | 3,442 | 2,530
Allowance for loan losses, Ending balance | 21,763 | 5,681 | 5,219
Allowance for loan losses, Individually Evaluated for impairment |  | 479 | 1
Allowance for loan losses, Collectively Evaluated for impairment |  | 5,202 | 5,218
Allowance for loan losses, Individually Evaluated for impairment |  | 3,146 | 2,034
Allowance for loan losses, Collectively Evaluated for impairment |  | 1,105,169 | 958,231
Loans, Ending balance | 1,256,525 | 1,108,315 | 960,265
Commercial Mortgage [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 7,310 |  |
Allowance for loan losses, Ending balance |  | 7,310 |
Commercial Mortgage [Member] | Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 12,991 |  |
Allowance for loan losses, Ending balance |  | 12,991 |
Residential Real Estate Loans [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 1,059 | 1,112 | 1,322
Allowance for loan losses, Charge-offs | (100) | (340) | (95)
Allowance for loan losses, Recoveries | 28 | 43 | 159
Allowance for loan losses, Provision (credit) | (353) | 244 | (274)
Allowance for loan losses, Ending balance | 3,924 | 1,059 | 1,112
Allowance for loan losses, Collectively Evaluated for impairment |  | 1,059 | 1,112
Allowance for loan losses, Collectively Evaluated for impairment |  | 560,717 | 514,981
Loans, Ending balance | 586,537 | 560,717 | 514,981
Residential Real Estate Loans [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 3,290 |  |
Allowance for loan losses, Ending balance |  | 3,290 |
Residential Real Estate Loans [Member] | Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 4,349 |  |
Allowance for loan losses, Ending balance |  | 4,349 |
Residential Real Estate Lines [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 118 | 210 | 180
Allowance for loan losses, Charge-offs |  | (13) | (142)
Allowance for loan losses, Recoveries | 3 | 6 | 20
Allowance for loan losses, Provision (credit) | (54) | (85) | 152
Allowance for loan losses, Ending balance | 674 | 118 | 210
Allowance for loan losses, Collectively Evaluated for impairment |  | 118 | 210
Allowance for loan losses, Collectively Evaluated for impairment |  | 101,048 | 106,712
Loans, Ending balance | 86,708 | 101,048 | 106,712
Residential Real Estate Lines [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 607 |  |
Allowance for loan losses, Ending balance |  | 607 |
Residential Real Estate Lines [Member] | Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 725 |  |
Allowance for loan losses, Ending balance |  | 725 |
Consumer Indirect [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 11,852 | 12,572 | 13,415
Allowance for loan losses, Charge-offs | (9,959) | (10,810) | (10,850)
Allowance for loan losses, Recoveries | 5,681 | 5,390 | 5,024
Allowance for loan losses, Provision (credit) | 5,825 | 4,700 | 4,983
Allowance for loan losses, Ending balance | 12,165 | 11,852 | 12,572
Allowance for loan losses, Collectively Evaluated for impairment |  | 11,852 | 12,572
Allowance for loan losses, Collectively Evaluated for impairment |  | 822,179 | 888,732
Loans, Ending balance | 812,816 | 822,179 | 888,732
Consumer Indirect [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | (1,234) |  |
Allowance for loan losses, Ending balance |  | (1,234) |
Consumer Indirect [Member] | Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 10,618 |  |
Allowance for loan losses, Ending balance |  | 10,618 |
Other Consumer [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | 414 | 489 | 391
Allowance for loan losses, Charge-offs | (681) | (1,170) | (1,308)
Allowance for loan losses, Recoveries | 352 | 387 | 317
Allowance for loan losses, Provision (credit) | 362 | 708 | 1,089
Allowance for loan losses, Ending balance | 314 | 414 | 489
Allowance for loan losses, Collectively Evaluated for impairment |  | 414 | 489
Allowance for loan losses, Collectively Evaluated for impairment |  | 15,984 | 16,590
Loans, Ending balance | 16,913 | 15,984 | $ 16,590
Other Consumer [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | (133) |  |
Allowance for loan losses, Ending balance |  | (133) |
Other Consumer [Member] | Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses, Beginning balance | $ 281 |  |
Allowance for loan losses, Ending balance |  | $ 281 |

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