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Allowance for Credit Losses - Loan Balances by Year of Origination and Internally Assigned Risk Rating (Details) - USD ($) $ in Thousands | Sep. 30, 2022 | Dec. 31, 2021
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Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | $ 952,159 | $ 1,380,130
Year two | 1,250,192 | 772,783
Year three | 614,941 | 961,071
Year four | 782,546 | 606,970
Year five | 474,779 | 431,724
More than five years | 1,608,076 | 1,591,979
Revolving | 1,387,431 | 1,226,925
Revolving-Term | 26,792 | 28,408
Total | 7,096,916 | 6,999,990
Pass |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 952,121 | 1,379,856
Year two | 1,231,943 | 768,961
Year three | 610,210 | 879,574
Year four | 734,404 | 576,166
Year five | 429,064 | 370,013
More than five years | 1,388,217 | 1,361,826
Revolving | 1,357,489 | 1,209,363
Revolving-Term | 23,224 | 24,964
Total | 6,726,672 | 6,570,723
Special mention |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 150
Year two | 14,934 | 151
Year three | 189 | 42,832
Year four | 20,036 | 10,312
Year five | 25,356 | 41,574
More than five years | 131,736 | 88,094
Revolving | 13,587 | 9,047
Revolving-Term | 95 | 111
Total | 205,933 | 192,271
Substandard |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 38 | 124
Year two | 3,315 | 3,671
Year three | 4,542 | 36,888
Year four | 28,106 | 20,492
Year five | 20,359 | 20,137
More than five years | 88,123 | 142,059
Revolving | 16,355 | 8,515
Revolving-Term | 3,473 | 3,333
Total | 164,311 | 235,219
Doubtful |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 1,777
Year four | 0 | 0
Year five | 0 | 0
More than five years | 0 | 0
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 0 | 1,777
Commercial Loans |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 5,239,648 | 5,406,584
Commercial Loans | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 228,599 | 385,347
Year two | 366,573 | 317,359
Year three | 279,472 | 468,720
Year four | 454,921 | 334,743
Year five | 273,477 | 266,019
More than five years | 938,489 | 881,391
Revolving | 21,051 | 36,948
Revolving-Term | 0 | 0
Total | 2,562,582 | 2,690,528
Commercial Loans | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 185,389 | 437,529
Year two | 308,442 | 126,371
Year three | 97,811 | 134,417
Year four | 89,270 | 86,912
Year five | 70,268 | 41,422
More than five years | 146,865 | 136,470
Revolving | 603,834 | 550,402
Revolving-Term | 0 | 0
Total | 1,501,879 | 1,513,523
Commercial Loans | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 83,458 | 142,321
Year two | 171,331 | 110,562
Year three | 43,840 | 113,532
Year four | 38,514 | 16,838
Year five | 4,331 | 989
More than five years | 5,047 | 10,477
Revolving | 28,758 | 30,036
Revolving-Term | 0 | 0
Total | 375,279 | 424,755
Commercial Loans | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 213,494 | 257,409
Year two | 240,779 | 108,048
Year three | 94,289 | 144,976
Year four | 119,394 | 115,228
Year five | 92,528 | 81,889
More than five years | 307,630 | 318,735
Revolving | 108,141 | 108,230
Revolving-Term | 1,348 | 1,179
Total | 1,177,603 | 1,135,693
Commercial Loans | Pass | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 228,599 | 385,347
Year two | 363,347 | 316,003
Year three | 278,153 | 412,191
Year four | 432,862 | 314,303
Year five | 238,351 | 213,019
More than five years | 760,947 | 698,992
Revolving | 21,051 | 35,448
Revolving-Term | 0 | 0
Total | 2,323,310 | 2,375,303
Commercial Loans | Pass | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 185,389 | 437,483
Year two | 293,593 | 126,371
Year three | 97,811 | 115,359
Year four | 72,039 | 83,030
Year five | 66,958 | 37,176
More than five years | 137,693 | 132,182
Revolving | 574,820 | 536,554
Revolving-Term | 0 | 0
Total | 1,428,303 | 1,468,155
Commercial Loans | Pass | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 83,458 | 142,321
Year two | 171,331 | 108,405
Year three | 43,840 | 111,512
Year four | 32,949 | 16,838
Year five | 4,331 | 989
More than five years | 3,150 | 3,539
Revolving | 28,758 | 30,036
Revolving-Term | 0 | 0
Total | 367,817 | 413,640
Commercial Loans | Pass | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 213,494 | 257,264
Year two | 240,694 | 107,791
Year three | 91,018 | 141,411
Year four | 116,429 | 110,586
Year five | 86,469 | 79,187
More than five years | 287,074 | 293,215
Revolving | 107,849 | 107,093
Revolving-Term | 679 | 443
Total | 1,143,706 | 1,096,990
Commercial Loans | Special mention | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 37,786
Year four | 9,407 | 6,401
Year five | 20,189 | 40,445
More than five years | 118,852 | 75,938
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 148,448 | 160,570
Commercial Loans | Special mention | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 46
Year two | 14,849 | 0
Year three | 0 | 3,060
Year four | 4,213 | 2,546
Year five | 2,091 | 72
More than five years | 7,193 | 832
Revolving | 13,466 | 8,887
Revolving-Term | 0 | 0
Total | 41,812 | 15,443
Commercial Loans | Special mention | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 0
Year four | 5,565 | 0
Year five | 0 | 0
More than five years | 0 | 4,458
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 5,565 | 4,458
Commercial Loans | Special mention | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 104
Year two | 85 | 151
Year three | 189 | 1,986
Year four | 851 | 1,365
Year five | 3,076 | 1,057
More than five years | 4,796 | 5,929
Revolving | 121 | 160
Revolving-Term | 95 | 111
Total | 9,213 | 10,863
Commercial Loans | Substandard | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 3,226 | 1,356
Year three | 1,319 | 18,743
Year four | 12,652 | 14,039
Year five | 14,937 | 12,555
More than five years | 58,690 | 106,461
Revolving | 0 | 1,500
Revolving-Term | 0 | 0
Total | 90,824 | 154,654
Commercial Loans | Substandard | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 14,221
Year four | 13,018 | 1,336
Year five | 1,219 | 4,174
More than five years | 1,979 | 3,456
Revolving | 15,548 | 4,961
Revolving-Term | 0 | 0
Total | 31,764 | 28,148
Commercial Loans | Substandard | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 2,157
Year three | 0 | 2,020
Year four | 0 | 0
Year five | 0 | 0
More than five years | 1,897 | 2,480
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 1,897 | 6,657
Commercial Loans | Substandard | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 41
Year two | 0 | 106
Year three | 3,082 | 1,579
Year four | 2,114 | 3,277
Year five | 2,983 | 1,645
More than five years | 15,760 | 19,591
Revolving | 171 | 977
Revolving-Term | 574 | 625
Total | 24,684 | 27,841
Commercial Loans | Doubtful | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 0
Year four | 0 | 0
Year five | 0 | 0
More than five years | 0 | 0
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 0 | 0
Commercial Loans | Doubtful | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 1,777
Year four | 0 | 0
Year five | 0 | 0
More than five years | 0 | 0
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 0 | 1,777
Commercial Loans | Doubtful | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 0
Year four | 0 | 0
Year five | 0 | 0
More than five years | 0 | 0
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 0 | 0
Commercial Loans | Doubtful | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 0
Year four | 0 | 0
Year five | 0 | 0
More than five years | 0 | 0
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 0 | 0
Consumer Loans |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 1,857,268 | 1,593,406
Consumer Loans | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total |  | 357,900
Consumer Loans | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 224,092 | 137,465
Year two | 151,021 | 100,995
Year three | 93,140 | 92,165
Year four | 76,389 | 50,156
Year five | 32,776 | 40,384
More than five years | 209,197 | 238,462
Revolving | 542,184 | 443,406
Revolving-Term | 24,166 | 24,552
Total | 1,352,965 | 1,127,585
Consumer Loans | Other Consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 17,127 | 20,059
Year two | 12,046 | 9,448
Year three | 6,389 | 7,261
Year four | 4,058 | 3,093
Year five | 1,399 | 1,021
More than five years | 848 | 6,444
Revolving | 83,463 | 57,903
Revolving-Term | 1,278 | 2,677
Total | 126,608 | 107,906
Consumer Loans | Pass | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 224,054 | 137,465
Year two | 150,932 | 100,995
Year three | 93,003 | 91,981
Year four | 76,097 | 48,531
Year five | 31,556 | 39,029
More than five years | 198,505 | 231,861
Revolving | 541,548 | 442,530
Revolving-Term | 21,267 | 23,391
Total | 1,336,962 | 1,115,783
Consumer Loans | Pass | Other Consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 17,127 | 19,976
Year two | 12,046 | 9,396
Year three | 6,385 | 7,120
Year four | 4,028 | 2,878
Year five | 1,399 | 613
More than five years | 848 | 2,037
Revolving | 83,463 | 57,702
Revolving-Term | 1,278 | 1,130
Total | 126,574 | 100,852
Consumer Loans | Special mention | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 0
Year four | 0 | 0
Year five | 0 | 0
More than five years | 895 | 937
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 895 | 937
Consumer Loans | Special mention | Other Consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 0
Year four | 0 | 0
Year five | 0 | 0
More than five years | 0 | 0
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 0 | 0
Consumer Loans | Substandard | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 38 | 0
Year two | 89 | 0
Year three | 137 | 184
Year four | 292 | 1,625
Year five | 1,220 | 1,355
More than five years | 9,797 | 5,664
Revolving | 636 | 876
Revolving-Term | 2,899 | 1,161
Total | 15,108 | 10,865
Consumer Loans | Substandard | Other Consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 83
Year two | 0 | 52
Year three | 4 | 141
Year four | 30 | 215
Year five | 0 | 408
More than five years | 0 | 4,407
Revolving | 0 | 201
Revolving-Term | 0 | 1,547
Total | 34 | 7,054
Consumer Loans | Doubtful | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 0
Year four | 0 | 0
Year five | 0 | 0
More than five years | 0 | 0
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 0 | 0
Consumer Loans | Doubtful | Other Consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 0
Year four | 0 | 0
Year five | 0 | 0
More than five years | 0 | 0
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | $ 0 | $ 0

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