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Allowance for Loan Losses - Investments in Loans Considered to be Impaired and Related Information on Impaired Loans (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Financing Receivable, Impaired [Line Items] |  |
With a related allowance recorded, Recorded Investment | $ 23,510 | $ 9,132
With a related allowance recorded, Unpaid Principal Balance | 24,821 | 9,141
Without a related allowance recorded, Recorded Investment | 51,827 | 40,374
Without a related allowance, Unpaid Principal Balance | 61,950 | 47,349
Impaired financing receivables | 75,337 | 49,506
Impaired Financing Receivable, Unpaid Principal Balance, Total | 86,771 | 56,490
Impaired Financing Receivable, Related Allowance, Total | 2,200 | 1,763
With a related allowance recorded, Average Recorded Investment | 24,655 | 8,967
With a related allowance recorded, Interest Income Recognized | 577 | 278
Without a related allowance recorded, Average Recorded Investment | 51,332 | 36,001
Without a related allowance recorded, Interest Income Recognized | 1,839 | 1,129
Impaired Financing Receivable, Average Recorded Investment, Total | 75,987 | 44,968
Impaired Financing Receivable, Interest Income Recognized, Total | 2,416 | 1,407
Commercial real estate |  |
Financing Receivable, Impaired [Line Items] |  |
With a related allowance recorded, Recorded Investment | 13,011 | 7,733
With a related allowance recorded, Unpaid Principal Balance | 14,322 | 7,733
Without a related allowance recorded, Recorded Investment | 34,909 | 3,636
Without a related allowance, Unpaid Principal Balance | 40,201 | 4,046
Impaired financing receivables | 47,920 | 11,369
Impaired Financing Receivable, Unpaid Principal Balance, Total | 54,523 | 11,779
Impaired Financing Receivable, Related Allowance, Total | 2,023 | 1,295
With a related allowance recorded, Average Recorded Investment | 14,018 | 7,780
With a related allowance recorded, Interest Income Recognized | 0 | 238
Without a related allowance recorded, Average Recorded Investment | 35,739 | 3,911
Without a related allowance recorded, Interest Income Recognized | 943 | 172
Impaired Financing Receivable, Average Recorded Investment, Total | 49,757 | 11,691
Impaired Financing Receivable, Interest Income Recognized, Total | 943 | 410
Commercial and industrial |  |
Financing Receivable, Impaired [Line Items] |  |
With a related allowance recorded, Recorded Investment | 10,001 | 884
With a related allowance recorded, Unpaid Principal Balance | 10,001 | 893
Without a related allowance recorded, Recorded Investment | 7,605 | 12,788
Without a related allowance, Unpaid Principal Balance | 10,358 | 14,452
Impaired financing receivables | 17,606 | 13,672
Impaired Financing Receivable, Unpaid Principal Balance, Total | 20,359 | 15,345
Impaired Financing Receivable, Related Allowance, Total | 55 | 360
With a related allowance recorded, Average Recorded Investment | 10,135 | 591
With a related allowance recorded, Interest Income Recognized | 576 | 38
Without a related allowance recorded, Average Recorded Investment | 5,565 | 4,722
Without a related allowance recorded, Interest Income Recognized | 368 | 257
Impaired Financing Receivable, Average Recorded Investment, Total | 15,700 | 5,313
Impaired Financing Receivable, Interest Income Recognized, Total | 944 | 295
Commercial construction |  |
Financing Receivable, Impaired [Line Items] |  |
With a related allowance recorded, Recorded Investment | 489 | 489
With a related allowance recorded, Unpaid Principal Balance | 489 | 489
Without a related allowance recorded, Recorded Investment | 1,425 | 15,286
Without a related allowance, Unpaid Principal Balance | 2,935 | 19,198
Impaired financing receivables | 1,914 | 15,775
Impaired Financing Receivable, Unpaid Principal Balance, Total | 3,424 | 19,687
Impaired Financing Receivable, Related Allowance, Total | 113 | 87
With a related allowance recorded, Average Recorded Investment | 489 | 561
With a related allowance recorded, Interest Income Recognized | 0 | 0
Without a related allowance recorded, Average Recorded Investment | 1,831 | 17,643
Without a related allowance recorded, Interest Income Recognized | 131 | 217
Impaired Financing Receivable, Average Recorded Investment, Total | 2,320 | 18,204
Impaired Financing Receivable, Interest Income Recognized, Total | 131 | 217
Consumer real estate |  |
Financing Receivable, Impaired [Line Items] |  |
With a related allowance recorded, Recorded Investment | 0 | 15
With a related allowance recorded, Unpaid Principal Balance | 0 | 14
Without a related allowance recorded, Recorded Investment | 7,884 | 8,659
Without a related allowance, Unpaid Principal Balance | 8,445 | 9,635
Impaired financing receivables | 7,884 | 8,674
Impaired Financing Receivable, Unpaid Principal Balance, Total | 8,445 | 9,649
Impaired Financing Receivable, Related Allowance, Total | 0 | 10
With a related allowance recorded, Average Recorded Investment | 0 | 16
With a related allowance recorded, Interest Income Recognized | 0 | 1
Without a related allowance recorded, Average Recorded Investment | 8,190 | 9,701
Without a related allowance recorded, Interest Income Recognized | 397 | 483
Impaired Financing Receivable, Average Recorded Investment, Total | 8,190 | 9,717
Impaired Financing Receivable, Interest Income Recognized, Total | 397 | 484
Other consumer |  |
Financing Receivable, Impaired [Line Items] |  |
With a related allowance recorded, Recorded Investment | 9 | 11
With a related allowance recorded, Unpaid Principal Balance | 9 | 12
Without a related allowance recorded, Recorded Investment | 4 | 5
Without a related allowance, Unpaid Principal Balance | 11 | 18
Impaired financing receivables | 13 | 16
Impaired Financing Receivable, Unpaid Principal Balance, Total | 20 | 30
Impaired Financing Receivable, Related Allowance, Total | 9 | 11
With a related allowance recorded, Average Recorded Investment | 13 | 19
With a related allowance recorded, Interest Income Recognized | 1 | 1
Without a related allowance recorded, Average Recorded Investment | 7 | 24
Without a related allowance recorded, Interest Income Recognized | 0 | 0
Impaired Financing Receivable, Average Recorded Investment, Total | 20 | 43
Impaired Financing Receivable, Interest Income Recognized, Total | $ 1 | $ 1

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