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Allowance for Credit Losses - Investments in Loans Considered to be Impaired and Related Information on Impaired Loans (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2019 | Sep. 30, 2019 | Dec. 31, 2019
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment |  |  | $ 23,510
With a related allowance recorded, Unpaid Principal Balance |  |  | 24,821
Impaired financing receivable, Related Allowance |  |  | 2,200
Without a related allowance recorded, Recorded Investment |  |  | 51,827
Without a related allowance, Unpaid Principal Balance |  |  | 61,950
Impaired Financing Receivable, Recorded Investment, Total |  |  | 75,337
Impaired Financing Receivable, Total Unpaid Principal Balance, Total |  |  | 86,771
With a related allowance recorded, Average Recorded Investment | $ 14,756 | $ 14,851 |
With a related allowance recorded, Interest Income Recognized | 0 | 1 |
Without a related allowance recorded, Average Recorded Investment | 58,338 | 57,747 |
Without a related allowance recorded, Interest Income Recognized | 478 | 1,434 |
Impaired financing receivable, Average Recorded Investment, Total | 73,094 | 72,598 |
Impaired financing Receivable, Interest Income Recognized, Total | 478 | 1,435 |
Commercial real estate | Commercial |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment |  |  | 13,011
With a related allowance recorded, Unpaid Principal Balance |  |  | 14,322
Impaired financing receivable, Related Allowance |  |  | 2,023
Without a related allowance recorded, Recorded Investment |  |  | 34,909
Without a related allowance, Unpaid Principal Balance |  |  | 40,201
Impaired Financing Receivable, Recorded Investment, Total |  |  | 47,920
Impaired Financing Receivable, Total Unpaid Principal Balance, Total |  |  | 54,523
With a related allowance recorded, Average Recorded Investment | 14,255 | 14,348 |
With a related allowance recorded, Interest Income Recognized | 0 | 0 |
Without a related allowance recorded, Average Recorded Investment | 39,179 | 39,788 |
Without a related allowance recorded, Interest Income Recognized | 231 | 712 |
Impaired financing receivable, Average Recorded Investment, Total | 53,434 | 54,136 |
Impaired financing Receivable, Interest Income Recognized, Total | 231 | 712 |
Commercial and industrial | Commercial |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment |  |  | 10,001
With a related allowance recorded, Unpaid Principal Balance |  |  | 10,001
Impaired financing receivable, Related Allowance |  |  | 55
Without a related allowance recorded, Recorded Investment |  |  | 7,605
Without a related allowance, Unpaid Principal Balance |  |  | 10,358
Impaired Financing Receivable, Recorded Investment, Total |  |  | 17,606
Impaired Financing Receivable, Total Unpaid Principal Balance, Total |  |  | 20,359
With a related allowance recorded, Average Recorded Investment | 0 | 0 |
With a related allowance recorded, Interest Income Recognized | 0 | 0 |
Without a related allowance recorded, Average Recorded Investment | 8,008 | 6,644 |
Without a related allowance recorded, Interest Income Recognized | 116 | 308 |
Impaired financing receivable, Average Recorded Investment, Total | 8,008 | 6,644 |
Impaired financing Receivable, Interest Income Recognized, Total | 116 | 308 |
Commercial construction | Commercial |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment |  |  | 489
With a related allowance recorded, Unpaid Principal Balance |  |  | 489
Impaired financing receivable, Related Allowance |  |  | 113
Without a related allowance recorded, Recorded Investment |  |  | 1,425
Without a related allowance, Unpaid Principal Balance |  |  | 2,935
Impaired Financing Receivable, Recorded Investment, Total |  |  | 1,914
Impaired Financing Receivable, Total Unpaid Principal Balance, Total |  |  | 3,424
With a related allowance recorded, Average Recorded Investment | 490 | 490 |
With a related allowance recorded, Interest Income Recognized | 0 | 0 |
Without a related allowance recorded, Average Recorded Investment | 2,318 | 2,318 |
Without a related allowance recorded, Interest Income Recognized | 34 | 117 |
Impaired financing receivable, Average Recorded Investment, Total | 2,808 | 2,808 |
Impaired financing Receivable, Interest Income Recognized, Total | 34 | 117 |
Consumer real estate | Consumer |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment |  |  | 0
With a related allowance recorded, Unpaid Principal Balance |  |  | 0
Impaired financing receivable, Related Allowance |  |  | 0
Without a related allowance recorded, Recorded Investment |  |  | 7,884
Without a related allowance, Unpaid Principal Balance |  |  | 8,445
Impaired Financing Receivable, Recorded Investment, Total |  |  | 7,884
Impaired Financing Receivable, Total Unpaid Principal Balance, Total |  |  | 8,445
With a related allowance recorded, Average Recorded Investment | 0 | 0 |
With a related allowance recorded, Interest Income Recognized | 0 | 0 |
Without a related allowance recorded, Average Recorded Investment | 8,830 | 8,993 |
Without a related allowance recorded, Interest Income Recognized | 97 | 297 |
Impaired financing receivable, Average Recorded Investment, Total | 8,830 | 8,993 |
Impaired financing Receivable, Interest Income Recognized, Total | 97 | 297 |
Other consumer | Consumer |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment |  |  | 9
With a related allowance recorded, Unpaid Principal Balance |  |  | 9
Impaired financing receivable, Related Allowance |  |  | 9
Without a related allowance recorded, Recorded Investment |  |  | 4
Without a related allowance, Unpaid Principal Balance |  |  | 11
Impaired Financing Receivable, Recorded Investment, Total |  |  | 13
Impaired Financing Receivable, Total Unpaid Principal Balance, Total |  |  | $ 20
With a related allowance recorded, Average Recorded Investment | 11 | 13 |
With a related allowance recorded, Interest Income Recognized | 0 | 1 |
Without a related allowance recorded, Average Recorded Investment | 3 | 4 |
Without a related allowance recorded, Interest Income Recognized | 0 | 0 |
Impaired financing receivable, Average Recorded Investment, Total | 14 | 17 |
Impaired financing Receivable, Interest Income Recognized, Total | $ 0 | $ 1 |

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