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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 | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment | $ 14,452 |  | $ 9,132
With a related allowance recorded, Unpaid Principal Balance | 14,461 |  | 9,141
Impaired financing receivable, Related Allowance | 3,023 |  | 1,763
Without a related allowance recorded, Recorded Investment | 41,852 |  | 40,374
Without a related allowance, Unpaid Principal Balance | 53,792 |  | 47,349
Impaired Financing Receivable, Recorded Investment, Total | 56,304 |  | 49,506
Impaired Financing Receivable, Total Unpaid Principal Balance, Total | 68,252 |  | 56,490
With a related allowance recorded, Average Recorded Investment | 14,476 | $ 628 |
With a related allowance recorded, Interest Income Recognized | 437 | 12 |
Without a related allowance recorded, Average Recorded Investment | 39,056 | 24,779 |
Without a related allowance recorded, Interest Income Recognized | 910 | 327 |
Impaired financing receivable, Average Recorded Investment, Total | 53,532 | 25,407 |
Impaired financing Receivable, Interest Income Recognized, Total | 1,347 | 339 |
Commercial real estate |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment | 12,965 |  | 7,733
With a related allowance recorded, Unpaid Principal Balance | 12,965 |  | 7,733
Impaired financing receivable, Related Allowance | 2,046 |  | 1,295
Without a related allowance recorded, Recorded Investment | 15,068 |  | 3,636
Without a related allowance, Unpaid Principal Balance | 17,895 |  | 4,046
Impaired Financing Receivable, Recorded Investment, Total | 28,033 |  | 11,369
Impaired Financing Receivable, Total Unpaid Principal Balance, Total | 30,860 |  | 11,779
With a related allowance recorded, Average Recorded Investment | 12,983 | 0 |
With a related allowance recorded, Interest Income Recognized | 400 | 0 |
Without a related allowance recorded, Average Recorded Investment | 15,107 | 3,817 |
Without a related allowance recorded, Interest Income Recognized | 144 | 43 |
Impaired financing receivable, Average Recorded Investment, Total | 28,090 | 3,817 |
Impaired financing Receivable, Interest Income Recognized, Total | 544 | 43 |
Commercial and industrial |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment | 976 |  | 884
With a related allowance recorded, Unpaid Principal Balance | 984 |  | 893
Impaired financing receivable, Related Allowance | 873 |  | 360
Without a related allowance recorded, Recorded Investment | 15,934 |  | 12,788
Without a related allowance, Unpaid Principal Balance | 22,551 |  | 14,452
Impaired Financing Receivable, Recorded Investment, Total | 16,910 |  | 13,672
Impaired Financing Receivable, Total Unpaid Principal Balance, Total | 23,535 |  | 15,345
With a related allowance recorded, Average Recorded Investment | 980 | 586 |
With a related allowance recorded, Interest Income Recognized | 35 | 11 |
Without a related allowance recorded, Average Recorded Investment | 12,780 | 6,688 |
Without a related allowance recorded, Interest Income Recognized | 209 | 110 |
Impaired financing receivable, Average Recorded Investment, Total | 13,760 | 7,274 |
Impaired financing Receivable, Interest Income Recognized, Total | 244 | 121 |
Commercial construction |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment | 489 |  | 489
With a related allowance recorded, Unpaid Principal Balance | 490 |  | 489
Impaired financing receivable, Related Allowance | 87 |  | 87
Without a related allowance recorded, Recorded Investment | 2,319 |  | 15,286
Without a related allowance, Unpaid Principal Balance | 3,828 |  | 19,198
Impaired Financing Receivable, Recorded Investment, Total | 2,808 |  | 15,775
Impaired Financing Receivable, Total Unpaid Principal Balance, Total | 4,318 |  | 19,687
With a related allowance recorded, Average Recorded Investment | 489 | 0 |
With a related allowance recorded, Interest Income Recognized | 0 | 0 |
Without a related allowance recorded, Average Recorded Investment | 2,319 | 3,446 |
Without a related allowance recorded, Interest Income Recognized | 140 | 36 |
Impaired financing receivable, Average Recorded Investment, Total | 2,808 | 3,446 |
Impaired financing Receivable, Interest Income Recognized, Total | 140 | 36 |
Consumer real estate |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment | 14 |  | 15
With a related allowance recorded, Unpaid Principal Balance | 14 |  | 14
Impaired financing receivable, Related Allowance | 9 |  | 10
Without a related allowance recorded, Recorded Investment | 8,527 |  | 8,659
Without a related allowance, Unpaid Principal Balance | 9,507 |  | 9,635
Impaired Financing Receivable, Recorded Investment, Total | 8,541 |  | 8,674
Impaired Financing Receivable, Total Unpaid Principal Balance, Total | 9,521 |  | 9,649
With a related allowance recorded, Average Recorded Investment | 14 | 0 |
With a related allowance recorded, Interest Income Recognized | 1 | 0 |
Without a related allowance recorded, Average Recorded Investment | 8,846 | 10,816 |
Without a related allowance recorded, Interest Income Recognized | 417 | 138 |
Impaired financing receivable, Average Recorded Investment, Total | 8,860 | 10,816 |
Impaired financing Receivable, Interest Income Recognized, Total | 418 | 138 |
Other consumer |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment | 8 |  | 11
With a related allowance recorded, Unpaid Principal Balance | 8 |  | 12
Impaired financing receivable, Related Allowance | 8 |  | 11
Without a related allowance recorded, Recorded Investment | 4 |  | 5
Without a related allowance, Unpaid Principal Balance | 10 |  | 18
Impaired Financing Receivable, Recorded Investment, Total | 12 |  | 16
Impaired Financing Receivable, Total Unpaid Principal Balance, Total | 18 |  | $ 30
With a related allowance recorded, Average Recorded Investment | 10 | 42 |
With a related allowance recorded, Interest Income Recognized | 1 | 1 |
Without a related allowance recorded, Average Recorded Investment | 4 | 12 |
Without a related allowance recorded, Interest Income Recognized | 0 | 0 |
Impaired financing receivable, Average Recorded Investment, Total | 14 | 54 |
Impaired financing Receivable, Interest Income Recognized, Total | $ 1 | $ 1 |

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