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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 | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | $ 9,706 |  | $ 9,706 |  | $ 9,132
With a related allowance recorded, Unpaid Principal Balance | 9,633 |  | 9,633 |  | 9,141
Impaired financing receivable, Related Allowance | 2,212 |  | 2,212 |  | 1,763
Without a related allowance recorded, Recorded Investment | 41,593 |  | 41,593 |  | 40,374
Without a related allowance, Unpaid Principal Balance | 49,696 |  | 49,696 |  | 47,349
Impaired Financing Receivable, Recorded Investment, Total | 51,299 |  | 51,299 |  | 49,506
Impaired Financing Receivable, Total Unpaid Principal Balance, Total | 59,329 |  | 59,329 |  | 56,490
With a related allowance recorded, Average Recorded Investment | 9,633 | $ 38 | 9,649 | $ 40 |
With a related allowance recorded, Interest Income Recognized | 13 | 1 | 27 | 2 |
Without a related allowance recorded, Average Recorded Investment | 39,643 | 24,605 | 37,723 | 25,092 |
Without a related allowance recorded, Interest Income Recognized | 349 | 415 | 584 | 629 |
Impaired financing receivable, Average Recorded Investment, Total | 49,276 | 24,643 | 47,373 | 25,132 |
Impaired financing Receivable, Interest Income Recognized, Total | 362 | 416 | 611 | 631 |
Commercial real estate |  |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | 7,703 |  | 7,703 |  | 7,733
With a related allowance recorded, Unpaid Principal Balance | 7,703 |  | 7,703 |  | 7,733
Impaired financing receivable, Related Allowance | 1,530 |  | 1,530 |  | 1,295
Without a related allowance recorded, Recorded Investment | 21,592 |  | 21,592 |  | 3,636
Without a related allowance, Unpaid Principal Balance | 24,894 |  | 24,894 |  | 4,046
Impaired Financing Receivable, Recorded Investment, Total | 29,295 |  | 29,295 |  | 11,369
Impaired Financing Receivable, Total Unpaid Principal Balance, Total | 32,597 |  | 32,597 |  | 11,779
With a related allowance recorded, Average Recorded Investment | 7,703 | 0 | 7,704 | 0 |
With a related allowance recorded, Interest Income Recognized | 0 | 0 | 0 | 0 |
Without a related allowance recorded, Average Recorded Investment | 21,802 | 3,609 | 22,093 | 3,712 |
Without a related allowance recorded, Interest Income Recognized | 77 | 54 | 124 | 85 |
Impaired financing receivable, Average Recorded Investment, Total | 29,505 | 3,609 | 29,797 | 3,712 |
Impaired financing Receivable, Interest Income Recognized, Total | 77 | 54 | 124 | 85 |
Commercial and industrial |  |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | 834 |  | 834 |  | 884
With a related allowance recorded, Unpaid Principal Balance | 761 |  | 761 |  | 893
Impaired financing receivable, Related Allowance | 204 |  | 204 |  | 360
Without a related allowance recorded, Recorded Investment | 9,817 |  | 9,817 |  | 12,788
Without a related allowance, Unpaid Principal Balance | 12,550 |  | 12,550 |  | 14,452
Impaired Financing Receivable, Recorded Investment, Total | 10,651 |  | 10,651 |  | 13,672
Impaired Financing Receivable, Total Unpaid Principal Balance, Total | 13,311 |  | 13,311 |  | 15,345
With a related allowance recorded, Average Recorded Investment | 758 | 0 | 772 | 0 |
With a related allowance recorded, Interest Income Recognized | 13 | 0 | 26 | 0 |
Without a related allowance recorded, Average Recorded Investment | 7,568 | 8,060 | 5,329 | 7,796 |
Without a related allowance recorded, Interest Income Recognized | 131 | 210 | 189 | 218 |
Impaired financing receivable, Average Recorded Investment, Total | 8,326 | 8,060 | 6,101 | 7,796 |
Impaired financing Receivable, Interest Income Recognized, Total | 144 | 210 | 215 | 218 |
Commercial construction |  |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | 490 |  | 490 |  | 489
With a related allowance recorded, Unpaid Principal Balance | 489 |  | 489 |  | 489
Impaired financing receivable, Related Allowance | 157 |  | 157 |  | 87
Without a related allowance recorded, Recorded Investment | 2,318 |  | 2,318 |  | 15,286
Without a related allowance, Unpaid Principal Balance | 3,828 |  | 3,828 |  | 19,198
Impaired Financing Receivable, Recorded Investment, Total | 2,808 |  | 2,808 |  | 15,775
Impaired Financing Receivable, Total Unpaid Principal Balance, Total | 4,317 |  | 4,317 |  | 19,687
With a related allowance recorded, Average Recorded Investment | 489 | 0 | 489 | 0 |
With a related allowance recorded, Interest Income Recognized | 0 | 0 | 0 | 0 |
Without a related allowance recorded, Average Recorded Investment | 2,319 | 3,443 | 2,319 | 3,445 |
Without a related allowance recorded, Interest Income Recognized | 48 | 33 | 83 | 73 |
Impaired financing receivable, Average Recorded Investment, Total | 2,808 | 3,443 | 2,808 | 3,445 |
Impaired financing Receivable, Interest Income Recognized, Total | 48 | 33 | 83 | 73 |
Consumer real estate |  |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | 666 |  | 666 |  | 15
With a related allowance recorded, Unpaid Principal Balance | 666 |  | 666 |  | 14
Impaired financing receivable, Related Allowance | 307 |  | 307 |  | 10
Without a related allowance recorded, Recorded Investment | 7,863 |  | 7,863 |  | 8,659
Without a related allowance, Unpaid Principal Balance | 8,415 |  | 8,415 |  | 9,635
Impaired Financing Receivable, Recorded Investment, Total | 8,529 |  | 8,529 |  | 8,674
Impaired Financing Receivable, Total Unpaid Principal Balance, Total | 9,081 |  | 9,081 |  | 9,649
With a related allowance recorded, Average Recorded Investment | 666 | 0 | 666 | 0 |
With a related allowance recorded, Interest Income Recognized | 0 | 0 | 0 | 0 |
Without a related allowance recorded, Average Recorded Investment | 7,952 | 9,483 | 7,979 | 10,128 |
Without a related allowance recorded, Interest Income Recognized | 93 | 118 | 188 | 253 |
Impaired financing receivable, Average Recorded Investment, Total | 8,618 | 9,483 | 8,645 | 10,128 |
Impaired financing Receivable, Interest Income Recognized, Total | 93 | 118 | 188 | 253 |
Other consumer |  |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | 13 |  | 13 |  | 11
With a related allowance recorded, Unpaid Principal Balance | 14 |  | 14 |  | 12
Impaired financing receivable, Related Allowance | 14 |  | 14 |  | 11
Without a related allowance recorded, Recorded Investment | 3 |  | 3 |  | 5
Without a related allowance, Unpaid Principal Balance | 9 |  | 9 |  | 18
Impaired Financing Receivable, Recorded Investment, Total | 16 |  | 16 |  | 16
Impaired Financing Receivable, Total Unpaid Principal Balance, Total | 23 |  | 23 |  | $ 30
With a related allowance recorded, Average Recorded Investment | 16 | 38 | 18 | 40 |
With a related allowance recorded, Interest Income Recognized | 0 | 1 | 1 | 2 |
Without a related allowance recorded, Average Recorded Investment | 3 | 10 | 4 | 11 |
Without a related allowance recorded, Interest Income Recognized | 0 | 0 | 0 | 0 |
Impaired financing receivable, Average Recorded Investment, Total | 19 | 48 | 22 | 51 |
Impaired financing Receivable, Interest Income Recognized, Total | $ 0 | $ 1 | $ 1 | $ 2 |

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