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Loans (Changes in the Allowance for Credit Losses) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | $ 52,420 | $ 30,482 | $ 33,914
Charge-offs | (13,219) | (21,625) | (17,811)
Recoveries | 7,459 | 7,810 | 6,335
Provision (benefit) | 6,984 | 26,159 | 8,044
Ending balance | 39,676 | 52,420 | 30,482
Allowance for loan losses, Individually Evaluated for impairment |  |  | 693
Allowance for loan losses, Collectively Evaluated for impairment |  |  | 29,789
Allowance for loan losses, Individually Evaluated for impairment |  |  | 4,323
Allowance for loan losses, Collectively Evaluated for impairment |  |  | 3,175,142
Investment securities, past due | 3,631,355 | 3,557,908 | 3,179,465
Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  | 9,594 |
Ending balance |  |  | 9,594
Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  | 40,076 |
Ending balance |  |  | 40,076
Commercial Business [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 13,580 | 11,358 | 14,312
Charge-offs | (669) | (9,093) | (2,481)
Recoveries | 881 | 1,709 | 492
Provision (benefit) | 2,693 | (9,852) | (965)
Ending balance | 11,099 | 13,580 | 11,358
Allowance for loan losses, Individually Evaluated for impairment |  |  | 214
Allowance for loan losses, Collectively Evaluated for impairment |  |  | 11,144
Allowance for loan losses, Individually Evaluated for impairment |  |  | 1,177
Allowance for loan losses, Collectively Evaluated for impairment |  |  | 570,045
Investment securities, past due | 639,368 | 798,409 | 571,222
Commercial Business [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  | (246) |
Ending balance |  |  | (246)
Commercial Business [Member] | Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  | 11,112 |
Ending balance |  |  | 11,112
Commercial Mortgage [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 21,763 | 5,681 | 5,219
Charge-offs | (3,999) | (1,792) | (2,997)
Recoveries | 185 | 37 | 17
Provision (benefit) | 3,172 | 10,527 | 3,442
Ending balance | 14,777 | 21,763 | 5,681
Allowance for loan losses, Individually Evaluated for impairment |  |  | 479
Allowance for loan losses, Collectively Evaluated for impairment |  |  | 5,202
Allowance for loan losses, Individually Evaluated for impairment |  |  | 3,146
Allowance for loan losses, Collectively Evaluated for impairment |  |  | 1,105,169
Investment securities, past due | 1,415,486 | 1,256,525 | 1,108,315
Commercial Mortgage [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  | 7,310 |
Ending balance |  |  | 7,310
Commercial Mortgage [Member] | Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  | 12,991 |
Ending balance |  |  | 12,991
Residential Real Estate Loans [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 3,924 | 1,059 | 1,112
Charge-offs | (148) | (100) | (340)
Recoveries | 92 | 28 | 43
Provision (benefit) | (2,264) | 353 | 244
Ending balance | 1,604 | 3,924 | 1,059
Allowance for loan losses, Collectively Evaluated for impairment |  |  | 1,059
Allowance for loan losses, Collectively Evaluated for impairment |  |  | 560,717
Investment securities, past due | 563,579 | 586,537 | 560,717
Residential Real Estate Loans [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  | 3,290 |
Ending balance |  |  | 3,290
Residential Real Estate Loans [Member] | Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  | 4,349 |
Ending balance |  |  | 4,349
Residential Real Estate Lines [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 674 | 118 | 210
Charge-offs | (141) | 0 | (13)
Recoveries | 0 | 3 | 6
Provision (benefit) | (154) | (54) | (85)
Ending balance | 379 | 674 | 118
Allowance for loan losses, Collectively Evaluated for impairment |  |  | 118
Allowance for loan losses, Collectively Evaluated for impairment |  |  | 101,048
Investment securities, past due | 75,515 | 86,708 | 101,048
Residential Real Estate Lines [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  | 607 |
Ending balance |  |  | 607
Residential Real Estate Lines [Member] | Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  | 725 |
Ending balance |  |  | 725
Consumer Indirect [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 12,165 | 11,852 | 12,572
Charge-offs | (7,236) | (9,959) | (10,810)
Recoveries | 5,980 | 5,681 | 5,390
Provision (benefit) | 702 | 5,825 | 4,700
Ending balance | 11,611 | 12,165 | 11,852
Allowance for loan losses, Collectively Evaluated for impairment |  |  | 11,852
Allowance for loan losses, Collectively Evaluated for impairment |  |  | 822,179
Investment securities, past due | 923,052 | 812,816 | 822,179
Consumer Indirect [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  | (1,234) |
Ending balance |  |  | (1,234)
Consumer Indirect [Member] | Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  | 10,618 |
Ending balance |  |  | 10,618
Other Consumer [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 314 | 414 | 489
Charge-offs | (1,026) | (681) | (1,170)
Recoveries | 321 | 352 | 387
Provision (benefit) | 597 | 362 | 708
Ending balance | 206 | 314 | 414
Allowance for loan losses, Collectively Evaluated for impairment |  |  | 414
Allowance for loan losses, Collectively Evaluated for impairment |  |  | 15,984
Investment securities, past due | $ 14,355 | 16,913 | 15,984
Other Consumer [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  | (133) |
Ending balance |  |  | (133)
Other Consumer [Member] | Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  | $ 281 |
Ending balance |  |  | $ 281

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