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Allowance for Credit Losses - Loan Balances by Year of Origination and Performing and Nonperforming Status (Details) - USD ($) $ in Thousands | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | $ 287,583 | $ 1,380,130
Year two | 1,310,234 | 772,783
Year three | 725,508 | 961,071
Year four | 880,093 | 606,970
Year five | 558,798 | 431,724
More than five years | 1,854,855 | 1,591,979
Revolving | 1,317,892 | 1,226,925
Revolving-Term | 28,948 | 28,408
Total | 6,963,911 | 6,999,990
Performing |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 287,583 | 1,380,089
Year two | 1,310,232 | 771,819
Year three | 724,479 | 940,641
Year four | 868,101 | 602,938
Year five | 554,835 | 421,125
More than five years | 1,822,457 | 1,564,501
Revolving | 1,315,743 | 1,224,949
Revolving-Term | 27,957 | 27,638
Total | 6,911,387 | 6,933,699
Nonperforming |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 41
Year two | 2 | 964
Year three | 1,029 | 20,430
Year four | 11,992 | 4,032
Year five | 3,963 | 10,599
More than five years | 32,398 | 27,478
Revolving | 2,149 | 1,976
Revolving-Term | 991 | 770
Total | 52,524 | 66,291
Commercial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 5,331,863 | 5,406,584
Commercial | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 92,158 | 385,347
Year two | 367,329 | 317,359
Year three | 335,124 | 468,720
Year four | 462,811 | 334,743
Year five | 328,712 | 266,019
More than five years | 1,083,184 | 881,391
Revolving | 36,481 | 36,948
Revolving-Term | 0 | 0
Total | 2,705,799 | 2,690,528
Commercial | Commercial real estate | Performing |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 92,158 | 385,347
Year two | 367,329 | 317,359
Year three | 335,124 | 461,613
Year four | 460,353 | 332,482
Year five | 326,451 | 259,723
More than five years | 1,062,113 | 865,567
Revolving | 36,481 | 36,948
Revolving-Term | 0 | 0
Total | 2,680,009 | 2,659,039
Commercial | Commercial real estate | Nonperforming |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 |
Year three | 0 | 7,107
Year four | 2,458 | 2,261
Year five | 2,261 | 6,296
More than five years | 21,071 | 15,824
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 25,790 | 31,488
Commercial | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 42,350 | 437,529
Year two | 369,108 | 126,371
Year three | 107,500 | 134,417
Year four | 113,383 | 86,912
Year five | 79,411 | 41,422
More than five years | 162,305 | 136,470
Revolving | 584,449 | 550,402
Revolving-Term | 0 | 0
Total | 1,458,506 | 1,513,523
Commercial | Commercial and industrial | Performing |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 42,350 | 437,529
Year two | 369,108 | 126,371
Year three | 107,500 | 123,944
Year four | 104,858 | 86,852
Year five | 79,353 | 38,540
More than five years | 162,248 | 136,427
Revolving | 582,519 | 548,622
Revolving-Term | 0 | 0
Total | 1,447,936 | 1,498,285
Commercial | Commercial and industrial | Nonperforming |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 10,473
Year four | 8,525 | 60
Year five | 58 | 2,882
More than five years | 57 | 43
Revolving | 1,930 | 1,780
Revolving-Term | 0 | 0
Total | 10,570 | 15,239
Commercial | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 24,551 | 142,321
Year two | 161,638 | 110,562
Year three | 72,342 | 113,532
Year four | 77,597 | 16,838
Year five | 4,988 | 989
More than five years | 11,095 | 10,477
Revolving | 31,026 | 30,036
Revolving-Term | 0 | 0
Total | 383,237 | 424,755
Commercial | Commercial construction | Performing |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 24,551 | 142,321
Year two | 161,638 | 110,562
Year three | 72,342 | 111,445
Year four | 77,117 | 16,838
Year five | 4,988 | 989
More than five years | 10,711 | 10,093
Revolving | 31,026 | 30,036
Revolving-Term | 0 | 0
Total | 382,373 | 422,284
Commercial | Commercial construction | Nonperforming |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 2,087
Year four | 480 | 0
Year five | 0 | 0
More than five years | 384 | 384
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 864 | 2,471
Commercial | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 66,205 | 257,409
Year two | 255,151 | 108,048
Year three | 105,295 | 144,976
Year four | 135,148 | 115,228
Year five | 106,319 | 81,889
More than five years | 361,297 | 318,735
Revolving | 110,593 | 108,230
Revolving-Term | 1,228 | 1,179
Total | 1,141,236 | 1,135,693
Commercial | Business banking | Performing |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 66,205 | 257,368
Year two | 255,149 | 107,984
Year three | 105,295 | 144,689
Year four | 134,873 | 113,820
Year five | 104,917 | 81,195
More than five years | 355,063 | 311,673
Revolving | 110,565 | 108,202
Revolving-Term | 1,172 | 1,122
Total | 1,133,239 | 1,126,052
Commercial | Business banking | Nonperforming |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 41
Year two | 2 | 64
Year three | 0 | 287
Year four | 275 | 1,408
Year five | 1,402 | 694
More than five years | 6,234 | 7,062
Revolving | 28 | 28
Revolving-Term | 56 | 57
Total | 7,997 | 9,641
Consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 1,632,048 | 1,593,406
Consumer | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total |  | 357,900
Consumer | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 56,284 | 137,465
Year two | 141,486 | 100,995
Year three | 97,071 | 92,165
Year four | 85,206 | 50,156
Year five | 36,916 | 40,384
More than five years | 235,623 | 238,462
Revolving | 483,849 | 443,406
Revolving-Term | 26,422 | 24,552
Total | 1,162,857 | 1,127,585
Consumer | Consumer real estate | Performing |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 56,284 | 137,465
Year two | 141,486 | 100,253
Year three | 96,167 | 91,689
Year four | 84,952 | 49,853
Year five | 36,674 | 39,657
More than five years | 230,971 | 234,297
Revolving | 483,658 | 443,238
Revolving-Term | 25,487 | 23,839
Total | 1,155,679 | 1,120,291
Consumer | Consumer real estate | Nonperforming |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 742
Year three | 904 | 476
Year four | 254 | 303
Year five | 242 | 727
More than five years | 4,652 | 4,165
Revolving | 191 | 168
Revolving-Term | 935 | 713
Total | 7,178 | 7,294
Consumer | Other consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 6,035 | 20,059
Year two | 15,522 | 9,448
Year three | 8,176 | 7,261
Year four | 5,948 | 3,093
Year five | 2,452 | 1,021
More than five years | 1,351 | 6,444
Revolving | 71,494 | 57,903
Revolving-Term | 1,298 | 2,677
Total | 112,276 | 107,906
Consumer | Other consumer | Performing |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 6,035 | 20,059
Year two | 15,522 | 9,290
Year three | 8,051 | 7,261
Year four | 5,948 | 3,093
Year five | 2,452 | 1,021
More than five years | 1,351 | 6,444
Revolving | 71,494 | 57,903
Revolving-Term | 1,298 | 2,677
Total | 112,151 | 107,748
Consumer | Other consumer | Nonperforming |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 158
Year three | 125 | 0
Year four | 0 | 0
Year five | 0 | 0
More than five years | 0 | 0
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | $ 125 | $ 158

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