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Allowance for Credit Losses - Loan Balances by Year of Origination and Internally Assigned Risk Rating (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
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 | Pass | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 385,347 | 334,086
Year two | 316,003 | 422,800
Year three | 412,191 | 394,963
Year four | 314,303 | 277,724
Year five | 213,019 | 307,321
More than five years | 698,992 | 615,217
Revolving | 35,448 | 46,330
Revolving-Term | 0 | 0
Total | 2,375,303 | 2,398,441
Commercial | Pass | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 437,483 | 454,131
Year two | 126,371 | 199,453
Year three | 115,359 | 140,049
Year four | 83,030 | 68,607
Year five | 37,176 | 27,645
More than five years | 132,182 | 206,782
Revolving | 536,554 | 383,082
Revolving-Term | 0 | 0
Total | 1,468,155 | 1,479,749
Commercial | Pass | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 142,321 | 131,235
Year two | 108,405 | 224,794
Year three | 111,512 | 59,649
Year four | 16,838 | 2,420
Year five | 989 | 6,346
More than five years | 3,539 | 4,555
Revolving | 30,036 | 12,778
Revolving-Term | 0 | 0
Total | 413,640 | 441,777
Commercial | Pass | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 257,264 | 296,254
Year two | 107,791 | 154,335
Year three | 141,411 | 123,207
Year four | 110,586 | 86,552
Year five | 79,187 | 77,238
More than five years | 293,215 | 266,042
Revolving | 107,093 | 103,571
Revolving-Term | 443 | 291
Total | 1,096,990 | 1,107,490
Commercial | Special Mention | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 35,499
Year three | 37,786 | 10,200
Year four | 6,401 | 22,502
Year five | 40,445 | 55,174
More than five years | 75,938 | 75,022
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 160,570 | 198,397
Commercial | Special Mention | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 46 | 3,697
Year two | 0 | 8,211
Year three | 3,060 | 2,628
Year four | 2,546 | 697
Year five | 72 | 768
More than five years | 832 | 1,046
Revolving | 8,887 | 23,527
Revolving-Term | 0 | 0
Total | 15,443 | 40,574
Commercial | Special Mention | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 1,578
Year two | 0 | 2,533
Year three | 0 | 3,886
Year four | 0 | 0
Year five | 0 | 0
More than five years | 4,458 | 8,593
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 4,458 | 16,590
Commercial | Special Mention | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 104 | 0
Year two | 151 | 1,060
Year three | 1,986 | 1,147
Year four | 1,365 | 1,602
Year five | 1,057 | 1,084
More than five years | 5,929 | 6,866
Revolving | 160 | 637
Revolving-Term | 111 | 123
Total | 10,863 | 12,519
Commercial | Substandard | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 1,356 | 17,259
Year three | 18,743 | 12,781
Year four | 14,039 | 19,914
Year five | 12,555 | 50,700
More than five years | 106,461 | 83,792
Revolving | 1,500 | 1,500
Revolving-Term | 0 | 0
Total | 154,654 | 185,946
Commercial | Substandard | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 7,793
Year three | 14,221 | 2,613
Year four | 1,336 | 8,544
Year five | 4,174 | 75
More than five years | 3,456 | 13,781
Revolving | 4,961 | 2,022
Revolving-Term | 0 | 0
Total | 28,148 | 34,828
Commercial | Substandard | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 2,157 | 3,580
Year three | 2,020 | 0
Year four | 0 | 501
Year five | 0 | 0
More than five years | 2,480 | 3,629
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 6,657 | 7,710
Commercial | Substandard | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 41 | 103
Year two | 106 | 1,078
Year three | 1,579 | 3,896
Year four | 3,277 | 3,209
Year five | 1,645 | 3,880
More than five years | 19,591 | 25,871
Revolving | 977 | 1,341
Revolving-Term | 625 | 680
Total | 27,841 | 40,058
Commercial | Doubtful | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 645
Year three | 0 | 0
Year four | 0 | 0
Year five | 0 | 1,989
More than five years | 0 | 6,529
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 0 | 9,163
Commercial | Doubtful | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 1,777 | 0
Year four | 0 | 4,401
Year five | 0 | 0
More than five years | 0 | 0
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 1,777 | 4,401
Commercial | 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 | 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 | 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 | Pass | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 137,465 | 120,736
Year two | 100,995 | 122,171
Year three | 91,981 | 67,700
Year four | 48,531 | 63,653
Year five | 39,029 | 73,805
More than five years | 231,861 | 243,939
Revolving | 442,530 | 438,888
Revolving-Term | 23,391 | 22,667
Total | 1,115,783 | 1,153,559
Consumer | Pass | Other consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 19,976 | 18,849
Year two | 9,396 | 13,162
Year three | 7,120 | 6,784
Year four | 2,878 | 3,395
Year five | 613 | 2,082
More than five years | 2,037 | 687
Revolving | 57,702 | 26,647
Revolving-Term | 1,130 | 2,767
Total | 100,852 | 74,373
Consumer | Special Mention | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 1,489
Year four | 0 | 0
Year five | 0 | 0
More than five years | 937 | 150
Revolving | 0 | 132
Revolving-Term | 0 | 0
Total | 937 | 1,771
Consumer | 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 | Substandard | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 373
Year three | 184 | 742
Year four | 1,625 | 1,480
Year five | 1,355 | 2,449
More than five years | 5,664 | 6,958
Revolving | 876 | 0
Revolving-Term | 1,161 | 0
Total | 10,865 | 12,002
Consumer | Substandard | Other consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 83 | 15
Year two | 52 | 0
Year three | 141 | 0
Year four | 215 | 0
Year five | 408 | 0
More than five years | 4,407 | 3,367
Revolving | 201 | 744
Revolving-Term | 1,547 | 2,386
Total | 7,054 | 6,512
Consumer | 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 | 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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