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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 |
--- | --- | ---
Mar. 31, 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 | $ 39,056 |
With a related allowance recorded, Interest Income Recognized | 910 |
Without a related allowance recorded, Average Recorded Investment | 14,476 |
Without a related allowance recorded, Interest Income Recognized | 437 |
Impaired financing receivable, Average Recorded Investment, Total | 53,532 |
Impaired financing Receivable, Interest Income Recognized, Total | 1,347 |
Commercial real estate |  |
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 | 15,107 |
With a related allowance recorded, Interest Income Recognized | 144 |
Without a related allowance recorded, Average Recorded Investment | 12,983 |
Without a related allowance recorded, Interest Income Recognized | 400 |
Impaired financing receivable, Average Recorded Investment, Total | 28,090 |
Impaired financing Receivable, Interest Income Recognized, Total | 544 |
Commercial and industrial |  |
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 | 12,780 |
With a related allowance recorded, Interest Income Recognized | 209 |
Without a related allowance recorded, Average Recorded Investment | 980 |
Without a related allowance recorded, Interest Income Recognized | 35 |
Impaired financing receivable, Average Recorded Investment, Total | 13,760 |
Impaired financing Receivable, Interest Income Recognized, Total | 244 |
Commercial construction |  |
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 | 2,319 |
With a related allowance recorded, Interest Income Recognized | 140 |
Without a related allowance recorded, Average Recorded Investment | 489 |
Without a related allowance recorded, Interest Income Recognized | 0 |
Impaired financing receivable, Average Recorded Investment, Total | 2,808 |
Impaired financing Receivable, Interest Income Recognized, Total | 140 |
Consumer real estate |  |
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 | 8,846 |
With a related allowance recorded, Interest Income Recognized | 417 |
Without a related allowance recorded, Average Recorded Investment | 14 |
Without a related allowance recorded, Interest Income Recognized | 1 |
Impaired financing receivable, Average Recorded Investment, Total | 8,860 |
Impaired financing Receivable, Interest Income Recognized, Total | 418 |
Other 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 | 4 |
With a related allowance recorded, Interest Income Recognized | 0 |
Without a related allowance recorded, Average Recorded Investment | 10 |
Without a related allowance recorded, Interest Income Recognized | 1 |
Impaired financing receivable, Average Recorded Investment, Total | 14 |
Impaired financing Receivable, Interest Income Recognized, Total | $ 1 |

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