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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 | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016 | Dec. 31, 2016
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | $ 2,520 |  | $ 2,520 |  | $ 991
With a related allowance recorded, Unpaid Principal Balance | 2,553 |  | 2,553 |  | 2,460
Impaired Financing Receivable, Related Allowance | 312 |  | 312 |  | 798
Without a related allowance recorded, Recorded Investment | 29,468 |  | 29,468 |  | 40,944
Without a related allowance, Unpaid Principal Balance | 35,868 |  | 35,868 |  | 48,539
Impaired Financing Receivable, Recorded Investment | 31,988 |  | 31,988 |  | 41,935
Impaired Financing Receivable, Unpaid Principal Balance, Total | 38,421 |  | 38,421 |  | 50,999
With a related allowance recorded, Average Recorded Investment | 2,461 | $ 2,467 | 36,321 | $ 35,365 |
With a related allowance recorded, Interest Income Recognized | 40 | 37 | 881 | 806 |
Without a related allowance recorded, Average Recorded Investment | 33,806 | 34,665 | 1,277 | 2,523 |
Without a related allowance recorded, Interest Income Recognized | 639 | 298 | 46 | 102 |
Impaired Financing Receivable, Average Recorded Investment, Total | 36,267 | 37,132 | 37,598 | 37,888 |
Impaired Financing Receivable, Interest Income Recognized, Total | 679 | 335 | 927 | 908 |
Commercial Real Estate |  |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | 0 |  | 0 |  | 0
With a related allowance recorded, Unpaid Principal Balance | 0 |  | 0 |  | 0
Impaired Financing Receivable, Related Allowance | 0 |  | 0 |  | 0
Without a related allowance recorded, Recorded Investment | 6,341 |  | 6,341 |  | 16,352
Without a related allowance, Unpaid Principal Balance | 6,985 |  | 6,985 |  | 17,654
Impaired Financing Receivable, Recorded Investment | 6,341 |  | 6,341 |  | 16,352
Impaired Financing Receivable, Unpaid Principal Balance, Total | 6,985 |  | 6,985 |  | 17,654
With a related allowance recorded, Average Recorded Investment | 0 | 0 | 6,577 | 7,551 |
With a related allowance recorded, Interest Income Recognized | 0 | 0 | 140 | 106 |
Without a related allowance recorded, Average Recorded Investment | 6,415 | 7,582 | 0 | 0 |
Without a related allowance recorded, Interest Income Recognized | 105 | 38 | 0 | 0 |
Impaired Financing Receivable, Average Recorded Investment, Total | 6,415 | 7,582 | 6,577 | 7,551 |
Impaired Financing Receivable, Interest Income Recognized, Total | 105 | 38 | 140 | 106 |
Commercial and Industrial |  |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | 2,468 |  | 2,468 |  | 964
With a related allowance recorded, Unpaid Principal Balance | 2,501 |  | 2,501 |  | 2,433
Impaired Financing Receivable, Related Allowance | 260 |  | 260 |  | 771
Without a related allowance recorded, Recorded Investment | 6,075 |  | 6,075 |  | 5,902
Without a related allowance, Unpaid Principal Balance | 8,245 |  | 8,245 |  | 7,699
Impaired Financing Receivable, Recorded Investment | 8,543 |  | 8,543 |  | 6,866
Impaired Financing Receivable, Unpaid Principal Balance, Total | 10,746 |  | 10,746 |  | 10,132
With a related allowance recorded, Average Recorded Investment | 2,406 | 2,437 | 11,001 | 7,447 |
With a related allowance recorded, Interest Income Recognized | 37 | 37 | 164 | 156 |
Without a related allowance recorded, Average Recorded Investment | 9,074 | 7,326 | 1,218 | 2,492 |
Without a related allowance recorded, Interest Income Recognized | 130 | 52 | 44 | 100 |
Impaired Financing Receivable, Average Recorded Investment, Total | 11,480 | 9,763 | 12,219 | 9,939 |
Impaired Financing Receivable, Interest Income Recognized, Total | 167 | 89 | 208 | 256 |
Commercial Construction |  |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | 0 |  | 0 |  |
With a related allowance recorded, Unpaid Principal Balance | 0 |  | 0 |  |
Impaired Financing Receivable, Related Allowance | 0 |  | 0 |  |
Without a related allowance recorded, Recorded Investment | 5,974 |  | 5,974 |  | 6,613
Without a related allowance, Unpaid Principal Balance | 8,629 |  | 8,629 |  | 10,306
Impaired Financing Receivable, Recorded Investment | 5,974 |  | 5,974 |  | 6,613
Impaired Financing Receivable, Unpaid Principal Balance, Total | 8,629 |  | 8,629 |  | 10,306
With a related allowance recorded, Average Recorded Investment | 0 | 0 | 7,222 | 8,498 |
With a related allowance recorded, Interest Income Recognized | 0 | 0 | 194 | 143 |
Without a related allowance recorded, Average Recorded Investment | 7,140 | 8,039 | 0 | 0 |
Without a related allowance recorded, Interest Income Recognized | 154 | 49 | 0 | 0 |
Impaired Financing Receivable, Average Recorded Investment, Total | 7,140 | 8,039 | 7,222 | 8,498 |
Impaired Financing Receivable, Interest Income Recognized, Total | 154 | 49 | 194 | 143 |
Consumer Real Estate |  |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | 22 |  | 22 |  | 26
With a related allowance recorded, Unpaid Principal Balance | 22 |  | 22 |  | 26
Impaired Financing Receivable, Related Allowance | 22 |  | 22 |  | 26
Without a related allowance recorded, Recorded Investment | 11,054 |  | 11,054 |  | 12,053
Without a related allowance, Unpaid Principal Balance | 11,979 |  | 11,979 |  | 12,849
Impaired Financing Receivable, Recorded Investment | 11,076 |  | 11,076 |  | 12,079
Impaired Financing Receivable, Unpaid Principal Balance, Total | 12,001 |  | 12,001 |  | 12,875
With a related allowance recorded, Average Recorded Investment | 23 | 28 | 11,488 | 11,831 |
With a related allowance recorded, Interest Income Recognized | 1 | 0 | 382 | 400 |
Without a related allowance recorded, Average Recorded Investment | 11,149 | 11,686 | 24 | 29 |
Without a related allowance recorded, Interest Income Recognized | 250 | 159 | 1 | 2 |
Impaired Financing Receivable, Average Recorded Investment, Total | 11,172 | 11,714 | 11,512 | 11,860 |
Impaired Financing Receivable, Interest Income Recognized, Total | 251 | 159 | 383 | 402 |
Other Consumer |  |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | 30 |  | 30 |  | 1
With a related allowance recorded, Unpaid Principal Balance | 30 |  | 30 |  | 1
Impaired Financing Receivable, Related Allowance | 30 |  | 30 |  | 1
Without a related allowance recorded, Recorded Investment | 24 |  | 24 |  | 24
Without a related allowance, Unpaid Principal Balance | 30 |  | 30 |  | 31
Impaired Financing Receivable, Recorded Investment | 54 |  | 54 |  | 25
Impaired Financing Receivable, Unpaid Principal Balance, Total | 60 |  | 60 |  | $ 32
With a related allowance recorded, Average Recorded Investment | 32 | 2 | 33 | 38 |
With a related allowance recorded, Interest Income Recognized | 2 | 0 | 1 | 1 |
Without a related allowance recorded, Average Recorded Investment | 28 | 32 | 35 | 2 |
Without a related allowance recorded, Interest Income Recognized | 0 | 0 | 1 | 0 |
Impaired Financing Receivable, Average Recorded Investment, Total | 60 | 34 | 68 | 40 |
Impaired Financing Receivable, Interest Income Recognized, Total | $ 2 | $ 0 | $ 2 | $ 1 |

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