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Allowance for Credit Losses - Loan Balances by Year of Origination and Internally Assigned Risk Rating (Details) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | $ 799,142 | $ 1,360,684
Year two | 966,097 | 1,214,746
Year three | 1,150,182 | 831,734
Year four | 712,097 | 565,201
Year five | 477,370 | 610,556
More than five years | 1,816,661 | 1,572,826
Revolving | 1,058,098 | 1,041,199
Revolving-Term | 27,703 | 28,914
Total | 7,007,351 | 7,225,860
Pass |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 793,541 | 1,355,291
Year two | 958,356 | 1,136,715
Year three | 1,060,518 | 792,352
Year four | 676,582 | 502,350
Year five | 408,589 | 494,436
More than five years | 1,504,535 | 1,337,221
Revolving | 1,039,420 | 1,011,297
Revolving-Term | 24,166 | 25,726
Total | 6,465,707 | 6,655,389
Special mention |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 168 | 5,274
Year two | 5,474 | 47,302
Year three | 56,894 | 19,350
Year four | 13,343 | 24,802
Year five | 40,492 | 57,026
More than five years | 131,379 | 91,677
Revolving | 11,861 | 24,296
Revolving-Term | 121 | 123
Total | 259,732 | 269,851
Substandard |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 5,433 | 118
Year two | 2,268 | 30,083
Year three | 32,019 | 20,032
Year four | 22,172 | 33,648
Year five | 28,289 | 57,105
More than five years | 174,983 | 137,398
Revolving | 6,818 | 5,607
Revolving-Term | 3,415 | 3,066
Total | 275,397 | 287,056
Doubtful |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 645
Year three | 751 | 0
Year four | 0 | 4,401
Year five | 0 | 1,989
More than five years | 5,764 | 6,529
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 6,514 | 13,564
Commercial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 5,499,044 | 5,673,707
Commercial | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 179,504 | 334,086
Year two | 326,979 | 476,203
Year three | 504,625 | 417,944
Year four | 370,957 | 320,140
Year five | 287,320 | 415,184
More than five years | 1,029,012 | 780,560
Revolving | 41,898 | 47,830
Revolving-Term | 0 | 0
Total | 2,740,296 | 2,791,947
Commercial | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 401,413 | 457,828
Year two | 268,962 | 215,457
Year three | 184,674 | 145,290
Year four | 107,731 | 82,249
Year five | 51,213 | 28,488
More than five years | 146,667 | 221,609
Revolving | 385,588 | 408,631
Revolving-Term | 0 | 0
Total | 1,546,247 | 1,559,552
Commercial | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 61,289 | 132,813
Year two | 130,376 | 230,907
Year three | 189,721 | 63,535
Year four | 48,374 | 2,921
Year five | 1,853 | 6,346
More than five years | 16,498 | 16,777
Revolving | 19,761 | 12,778
Revolving-Term | 0 | 0
Total | 467,871 | 466,077
Commercial | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 100,917 | 296,357
Year two | 116,374 | 156,473
Year three | 162,338 | 128,250
Year four | 128,737 | 91,363
Year five | 88,133 | 82,202
More than five years | 367,340 | 298,779
Revolving | 105,808 | 105,549
Revolving-Term | 1,228 | 1,094
Total | 1,070,875 | 1,160,067
Commercial | Pass | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 179,504 | 334,086
Year two | 326,531 | 422,800
Year three | 457,287 | 394,963
Year four | 347,132 | 277,724
Year five | 229,164 | 307,321
More than five years | 778,930 | 615,217
Revolving | 40,398 | 46,330
Revolving-Term | 0 | 0
Total | 2,358,945 | 2,398,441
Commercial | Pass | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 395,929 | 454,131
Year two | 265,953 | 199,453
Year three | 153,588 | 140,049
Year four | 102,789 | 68,607
Year five | 45,641 | 27,645
More than five years | 140,169 | 206,782
Revolving | 370,282 | 383,082
Revolving-Term | 0 | 0
Total | 1,474,351 | 1,479,749
Commercial | Pass | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 61,289 | 131,235
Year two | 126,858 | 224,794
Year three | 182,394 | 59,649
Year four | 48,374 | 2,420
Year five | 1,352 | 6,346
More than five years | 5,131 | 4,555
Revolving | 19,761 | 12,778
Revolving-Term | 0 | 0
Total | 445,159 | 441,777
Commercial | Pass | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 100,800 | 296,254
Year two | 115,666 | 154,335
Year three | 158,725 | 123,207
Year four | 123,708 | 86,552
Year five | 85,193 | 77,238
More than five years | 337,243 | 266,042
Revolving | 104,566 | 103,571
Revolving-Term | 455 | 291
Total | 1,026,356 | 1,107,490
Commercial | Special mention | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 448 | 35,499
Year three | 29,581 | 10,200
Year four | 8,310 | 22,502
Year five | 38,927 | 55,174
More than five years | 112,654 | 75,022
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 189,920 | 198,397
Commercial | Special mention | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 51 | 3,697
Year two | 3,008 | 8,211
Year three | 22,124 | 2,628
Year four | 3,369 | 697
Year five | 0 | 768
More than five years | 1,141 | 1,046
Revolving | 11,574 | 23,527
Revolving-Term | 0 | 0
Total | 41,266 | 40,574
Commercial | Special mention | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 1,578
Year two | 1,380 | 2,533
Year three | 3,269 | 3,886
Year four | 0 | 0
Year five | 0 | 0
More than five years | 8,421 | 8,593
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 13,071 | 16,590
Commercial | Special mention | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 117 | 0
Year two | 637 | 1,060
Year three | 1,919 | 1,147
Year four | 1,665 | 1,602
Year five | 1,564 | 1,084
More than five years | 6,958 | 6,866
Revolving | 287 | 637
Revolving-Term | 121 | 123
Total | 13,270 | 12,519
Commercial | Substandard | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 17,259
Year three | 17,007 | 12,781
Year four | 15,516 | 19,914
Year five | 19,229 | 50,700
More than five years | 131,668 | 83,792
Revolving | 1,500 | 1,500
Revolving-Term | 0 | 0
Total | 184,920 | 185,946
Commercial | Substandard | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 5,433 | 0
Year two | 0 | 7,793
Year three | 8,962 | 2,613
Year four | 1,573 | 8,544
Year five | 5,572 | 75
More than five years | 5,357 | 13,781
Revolving | 3,733 | 2,022
Revolving-Term | 0 | 0
Total | 30,630 | 34,828
Commercial | Substandard | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 2,138 | 3,580
Year three | 4,058 | 0
Year four | 0 | 501
Year five | 500 | 0
More than five years | 2,945 | 3,629
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 9,642 | 7,710
Commercial | Substandard | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 103
Year two | 72 | 1,078
Year three | 1,694 | 3,896
Year four | 3,364 | 3,209
Year five | 1,376 | 3,880
More than five years | 23,139 | 25,871
Revolving | 954 | 1,341
Revolving-Term | 651 | 680
Total | 31,249 | 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 | 751 | 0
Year four | 0 | 0
Year five | 0 | 1,989
More than five years | 5,760 | 6,529
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 6,511 | 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 | 0 | 0
Year four | 0 | 4,401
Year five | 0 | 0
More than five years | 0 | 0
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 0 | 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 |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 1,508,307 | 1,552,153
Consumer | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total |  | 303,900
Consumer | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 43,351 | 120,736
Year two | 111,123 | 122,544
Year three | 98,869 | 69,931
Year four | 51,411 | 65,133
Year five | 46,628 | 76,254
More than five years | 250,463 | 251,047
Revolving | 468,158 | 439,020
Revolving-Term | 23,875 | 22,667
Total | 1,093,878 | 1,167,332
Consumer | Other consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 12,668 | 18,864
Year two | 12,283 | 13,162
Year three | 9,955 | 6,784
Year four | 4,887 | 3,395
Year five | 2,223 | 2,082
More than five years | 6,681 | 4,054
Revolving | 36,886 | 27,391
Revolving-Term | 2,600 | 5,153
Total | 88,184 | 80,885
Consumer | Pass | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 43,351 | 120,736
Year two | 111,065 | 122,171
Year three | 98,684 | 67,700
Year four | 49,815 | 63,653
Year five | 45,224 | 73,805
More than five years | 241,295 | 243,939
Revolving | 467,802 | 438,888
Revolving-Term | 22,670 | 22,667
Total | 1,079,907 | 1,153,559
Consumer | Pass | Other consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 12,668 | 18,849
Year two | 12,283 | 13,162
Year three | 9,842 | 6,784
Year four | 4,764 | 3,395
Year five | 2,016 | 2,082
More than five years | 1,767 | 687
Revolving | 36,611 | 26,647
Revolving-Term | 1,040 | 2,767
Total | 80,990 | 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 | 2,205 | 150
Revolving | 0 | 132
Revolving-Term | 0 | 0
Total | 2,205 | 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 | 58 | 373
Year three | 185 | 742
Year four | 1,595 | 1,480
Year five | 1,404 | 2,449
More than five years | 6,963 | 6,958
Revolving | 356 | 0
Revolving-Term | 1,205 | 0
Total | 11,766 | 12,002
Consumer | Substandard | Other consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 15
Year two | 0 | 0
Year three | 113 | 0
Year four | 123 | 0
Year five | 208 | 0
More than five years | 4,910 | 3,367
Revolving | 275 | 744
Revolving-Term | 1,560 | 2,386
Total | 7,190 | 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 | 4 | 0
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | $ 4 | $ 0

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