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Allowance for Credit Losses - Loan Balances by Year of Origination and Performing and Nonperforming Status (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
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Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | $ 1,380,130 | $ 1,360,684
Year two | 772,783 | 1,214,746
Year three | 961,071 | 831,734
Year four | 606,970 | 565,201
Year five | 431,724 | 610,556
More than five years | 1,591,979 | 1,572,826
Revolving | 1,226,925 | 1,041,199
Revolving-Term | 28,408 | 28,914
Total | 6,999,990 | 7,225,860
Performing TDRs |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 1,380,089 | 1,360,654
Year two | 771,819 | 1,196,491
Year three | 940,641 | 827,625
Year four | 602,938 | 543,253
Year five | 421,125 | 586,622
More than five years | 1,564,501 | 1,496,135
Revolving | 1,224,949 | 1,040,544
Revolving-Term | 27,638 | 27,762
Total | 6,933,699 | 7,079,086
Nonperforming TDRs |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 41 | 30
Year two | 964 | 18,254
Year three | 20,430 | 4,108
Year four | 4,032 | 21,948
Year five | 10,599 | 23,934
More than five years | 27,478 | 76,691
Revolving | 1,976 | 654
Revolving-Term | 770 | 1,153
Total | 66,291 | 146,774
Commercial | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 385,347 | 334,086
Year two | 317,359 | 476,203
Year three | 468,720 | 417,944
Year four | 334,743 | 320,140
Year five | 266,019 | 415,184
More than five years | 881,391 | 780,560
Revolving | 36,948 | 47,830
Revolving-Term | 0 | 0
Total | 2,690,528 | 2,791,947
Commercial | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 437,529 | 457,828
Year two | 126,371 | 215,457
Year three | 134,417 | 145,290
Year four | 86,912 | 82,249
Year five | 41,422 | 28,488
More than five years | 136,470 | 221,609
Revolving | 550,402 | 408,631
Revolving-Term | 0 | 0
Total | 1,513,523 | 1,559,552
Commercial | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 142,321 | 132,813
Year two | 110,562 | 230,907
Year three | 113,532 | 63,535
Year four | 16,838 | 2,921
Year five | 989 | 6,346
More than five years | 10,477 | 16,777
Revolving | 30,036 | 12,778
Revolving-Term | 0 | 0
Total | 424,755 | 466,077
Commercial | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 257,409 | 296,357
Year two | 108,048 | 156,473
Year three | 144,976 | 128,250
Year four | 115,228 | 91,363
Year five | 81,889 | 82,202
More than five years | 318,735 | 298,779
Revolving | 108,230 | 105,549
Revolving-Term | 1,179 | 1,094
Total | 1,135,693 | 1,160,067
Commercial | Performing TDRs | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 385,347 | 334,086
Year two | 317,359 | 459,799
Year three | 461,613 | 417,944
Year four | 332,482 | 313,465
Year five | 259,723 | 394,972
More than five years | 865,567 | 722,782
Revolving | 36,948 | 47,830
Revolving-Term | 0 | 0
Total | 2,659,039 | 2,690,879
Commercial | Performing TDRs | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 437,529 | 457,828
Year two | 126,371 | 214,144
Year three | 123,944 | 143,706
Year four | 86,852 | 69,411
Year five | 38,540 | 28,426
More than five years | 136,427 | 220,701
Revolving | 548,622 | 408,350
Revolving-Term | 0 | 0
Total | 1,498,285 | 1,542,566
Commercial | Performing TDRs | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 142,321 | 132,813
Year two | 110,562 | 230,907
Year three | 111,445 | 63,535
Year four | 16,838 | 2,921
Year five | 989 | 6,346
More than five years | 10,093 | 16,393
Revolving | 30,036 | 12,778
Revolving-Term | 0 | 0
Total | 422,284 | 465,692
Commercial | Performing TDRs | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 257,368 | 296,327
Year two | 107,984 | 156,164
Year three | 144,689 | 126,432
Year four | 113,820 | 90,414
Year five | 81,195 | 80,106
More than five years | 311,673 | 286,970
Revolving | 108,202 | 105,494
Revolving-Term | 1,122 | 1,037
Total | 1,126,052 | 1,142,944
Commercial | Nonperforming TDRs | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two |  | 16,404
Year three | 7,107 | 0
Year four | 2,261 | 6,675
Year five | 6,296 | 20,212
More than five years | 15,824 | 57,778
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 31,488 | 101,070
Commercial | Nonperforming TDRs | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 1,313
Year three | 10,473 | 1,584
Year four | 60 | 12,838
Year five | 2,882 | 62
More than five years | 43 | 908
Revolving | 1,780 | 281
Revolving-Term | 0 | 0
Total | 15,239 | 16,985
Commercial | Nonperforming TDRs | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 2,087 | 0
Year four | 0 | 0
Year five | 0 | 0
More than five years | 384 | 384
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 2,471 | 384
Commercial | Nonperforming TDRs | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 41 | 30
Year two | 64 | 309
Year three | 287 | 1,818
Year four | 1,408 | 949
Year five | 694 | 2,096
More than five years | 7,062 | 11,809
Revolving | 28 | 55
Revolving-Term | 57 | 57
Total | 9,641 | 17,123
Consumer | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 137,465 | 120,736
Year two | 100,995 | 122,544
Year three | 92,165 | 69,931
Year four | 50,156 | 65,133
Year five | 40,384 | 76,254
More than five years | 238,462 | 251,047
Revolving | 443,406 | 439,020
Revolving-Term | 24,552 | 22,667
Total | 1,127,585 | 1,167,332
Consumer | Other consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 20,059 | 18,864
Year two | 9,448 | 13,162
Year three | 7,261 | 6,784
Year four | 3,093 | 3,395
Year five | 1,021 | 2,082
More than five years | 6,444 | 4,054
Revolving | 57,903 | 27,391
Revolving-Term | 2,677 | 5,153
Total | 107,906 | 80,885
Consumer | Performing TDRs | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 137,465 | 120,736
Year two | 100,253 | 122,315
Year three | 91,689 | 69,225
Year four | 49,853 | 63,647
Year five | 39,657 | 74,690
More than five years | 234,297 | 245,331
Revolving | 443,238 | 438,702
Revolving-Term | 23,839 | 21,572
Total | 1,120,291 | 1,156,216
Consumer | Performing TDRs | Other consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 20,059 | 18,864
Year two | 9,290 | 13,162
Year three | 7,261 | 6,784
Year four | 3,093 | 3,395
Year five | 1,021 | 2,082
More than five years | 6,444 | 3,958
Revolving | 57,903 | 27,391
Revolving-Term | 2,677 | 5,153
Total | 107,748 | 80,789
Consumer | Nonperforming TDRs | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 742 | 229
Year three | 476 | 706
Year four | 303 | 1,486
Year five | 727 | 1,564
More than five years | 4,165 | 5,716
Revolving | 168 | 318
Revolving-Term | 713 | 1,096
Total | 7,294 | 11,116
Consumer | Nonperforming TDRs | Other consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 158 | 0
Year three | 0 | 0
Year four | 0 | 0
Year five | 0 | 0
More than five years | 0 | 96
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | $ 158 | $ 96

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