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Loans (Changes in the Allowance for Credit Losses) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | $ 39,676 | $ 52,420 | $ 30,482
Charge-offs | (16,720) | (13,219) | (21,625)
Recoveries | 11,482 | 7,459 | 7,810
Provision (benefit) | 10,975 | (6,984) | 26,159
Ending balance | 45,413 | 39,676 | 52,420
Investment securities, past due | 3,998,718 | 3,631,355 |
Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  |  | 9,594
Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  |  | 40,076
Commercial Business [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 11,099 | 13,580 | 11,358
Charge-offs | (312) | (669) | (9,093)
Recoveries | 376 | 881 | 1,709
Provision (benefit) | 1,422 | (2,693) | 9,852
Ending balance | 12,585 | 11,099 | 13,580
Investment securities, past due | 663,611 | 639,368 |
Commercial Business [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  |  | (246)
Commercial Business [Member] | Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  |  | 11,112
Commercial Mortgage [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 14,777 | 21,763 | 5,681
Charge-offs | (1,170) | (3,999) | (1,792)
Recoveries | 2,023 | 185 | 37
Provision (benefit) | (1,218) | (3,172) | 10,527
Ending balance | 14,412 | 14,777 | 21,763
Investment securities, past due | 1,683,814 | 1,415,486 |
Commercial Mortgage [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning 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
Residential Real Estate Loans [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 1,604 | 3,924 | 1,059
Charge-offs | (303) | (148) | (100)
Recoveries | 24 | 92 | 28
Provision (benefit) | 1,976 | (2,264) | (353)
Ending balance | 3,301 | 1,604 | 3,924
Investment securities, past due | 576,279 | 563,579 |
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
Residential Real Estate Loans [Member] | Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  |  | 4,349
Residential Real Estate Lines [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 379 | 674 | 118
Charge-offs | (38) | (141) | 0
Recoveries | 39 | 0 | 3
Provision (benefit) | 228 | (154) | (54)
Ending balance | 608 | 379 | 674
Investment securities, past due | 74,432 | 75,515 |
Residential Real Estate Lines [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning 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
Consumer Indirect [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 11,611 | 12,165 | 11,852
Charge-offs | (13,215) | (7,236) | (9,959)
Recoveries | 8,677 | 5,980 | 5,681
Provision (benefit) | 7,165 | 702 | 5,825
Ending balance | 14,238 | 11,611 | 12,165
Investment securities, past due | 985,580 | 923,052 |
Consumer Indirect [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning 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
Other Consumer [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 206 | 314 | 414
Charge-offs | (1,682) | (1,026) | (681)
Recoveries | 343 | 321 | 352
Provision (benefit) | 1,402 | 597 | 362
Ending balance | 269 | 206 | 314
Investment securities, past due | $ 15,002 | $ 14,355 |
Other Consumer [Member] | Cumulative-Effect Adjustment [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  |  | (133)
Other Consumer [Member] | Adjusted Balance [Member] | ASU 2016-13 [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance |  |  | $ 281

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