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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, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016 | Dec. 31, 2016
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | $ 2,492 |  | $ 2,492 |  | $ 991
With a related allowance recorded, Unpaid Principal Balance | 2,492 |  | 2,492 |  | 2,460
Impaired Financing Receivable, Related Allowance | 389 |  | 389 |  | 798
Without a related allowance recorded, Recorded Investment | 37,970 |  | 37,970 |  | 40,944
Without a related allowance, Unpaid Principal Balance | 43,901 |  | 43,901 |  | 48,539
Without a related allowance recorded, Related Allowance | 0 |  | 0 |  | 0
Impaired Financing Receivable, Recorded Investment | 40,462 |  | 40,462 |  | 41,935
Impaired Financing Receivable, Unpaid Principal Balance, Total | 46,393 |  | 46,393 |  | 50,999
With a related allowance recorded, Average Recorded Investment | 863 | $ 5,879 | 39,203 | $ 47,849 |
With a related allowance recorded, Interest Income Recognized | 7 | 38 | 528 | 673 |
Without a related allowance recorded, Average Recorded Investment | 40,112 | 47,269 | 680 | 6,275 |
Without a related allowance recorded, Interest Income Recognized | 298 | 317 | 13 | 76 |
Impaired Financing Receivable, Average Recorded Investment, Total | 40,975 | 53,148 | 39,883 | 54,124 |
Impaired Financing Receivable, Interest Income Recognized, Total | 305 | 355 | 541 | 749 |
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 | 6,472 |  | 6,472 |  | 16,352
Without a related allowance, Unpaid Principal Balance | 7,472 |  | 7,472 |  | 17,654
Without a related allowance recorded, Related Allowance | 0 |  | 0 |  | 0
Impaired Financing Receivable, Recorded Investment | 6,472 |  | 6,472 |  | 16,352
Impaired Financing Receivable, Unpaid Principal Balance, Total | 7,472 |  | 7,472 |  | 17,654
With a related allowance recorded, Average Recorded Investment | 0 | 0 | 7,028 | 14,798 |
With a related allowance recorded, Interest Income Recognized | 0 | 0 | 70 | 132 |
Without a related allowance recorded, Average Recorded Investment | 6,934 | 14,619 | 0 | 0 |
Without a related allowance recorded, Interest Income Recognized | 35 | 64 | 0 | 0 |
Impaired Financing Receivable, Average Recorded Investment, Total | 6,934 | 14,619 | 7,028 | 14,798 |
Impaired Financing Receivable, Interest Income Recognized, Total | 35 | 64 | 70 | 132 |
Commercial and Industrial |  |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | 2,443 |  | 2,443 |  | 964
With a related allowance recorded, Unpaid Principal Balance | 2,443 |  | 2,443 |  | 2,433
Impaired Financing Receivable, Related Allowance | 340 |  | 340 |  | 771
Without a related allowance recorded, Recorded Investment | 16,125 |  | 16,125 |  | 5,902
Without a related allowance, Unpaid Principal Balance | 18,097 |  | 18,097 |  | 7,699
Without a related allowance recorded, Related Allowance | 0 |  | 0 |  | 0
Impaired Financing Receivable, Recorded Investment | 18,568 |  | 18,568 |  | 6,866
Impaired Financing Receivable, Unpaid Principal Balance, Total | 20,540 |  | 20,540 |  | 10,132
With a related allowance recorded, Average Recorded Investment | 813 | 4,617 | 16,382 | 11,253 |
With a related allowance recorded, Interest Income Recognized | 6 | 31 | 124 | 189 |
Without a related allowance recorded, Average Recorded Investment | 17,625 | 10,959 | 628 | 4,999 |
Without a related allowance recorded, Interest Income Recognized | 95 | 98 | 11 | 63 |
Impaired Financing Receivable, Average Recorded Investment, Total | 18,438 | 15,576 | 17,010 | 16,252 |
Impaired Financing Receivable, Interest Income Recognized, Total | 101 | 129 | 135 | 252 |
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 | 4,257 |  | 4,257 |  | 6,613
Without a related allowance, Unpaid Principal Balance | 6,295 |  | 6,295 |  | 10,306
Without a related allowance recorded, Related Allowance | 0 |  | 0 |  | 0
Impaired Financing Receivable, Recorded Investment | 4,257 |  | 4,257 |  | 6,613
Impaired Financing Receivable, Unpaid Principal Balance, Total | 6,295 |  | 6,295 |  | 10,306
With a related allowance recorded, Average Recorded Investment | 0 | 1,232 | 4,267 | 10,669 |
With a related allowance recorded, Interest Income Recognized | 0 | 6 | 79 | 108 |
Without a related allowance recorded, Average Recorded Investment | 4,262 | 10,625 | 0 | 1,244 |
Without a related allowance recorded, Interest Income Recognized | 42 | 48 | 0 | 12 |
Impaired Financing Receivable, Average Recorded Investment, Total | 4,262 | 11,857 | 4,267 | 11,913 |
Impaired Financing Receivable, Interest Income Recognized, Total | 42 | 54 | 79 | 120 |
Consumer Real Estate |  |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | 24 |  | 24 |  | 26
With a related allowance recorded, Unpaid Principal Balance | 24 |  | 24 |  | 26
Impaired Financing Receivable, Related Allowance | 24 |  | 24 |  | 26
Without a related allowance recorded, Recorded Investment | 11,106 |  | 11,106 |  | 12,053
Without a related allowance, Unpaid Principal Balance | 12,024 |  | 12,024 |  | 12,849
Without a related allowance recorded, Related Allowance | 0 |  | 0 |  | 0
Impaired Financing Receivable, Recorded Investment | 11,130 |  | 11,130 |  | 12,079
Impaired Financing Receivable, Unpaid Principal Balance, Total | 12,048 |  | 12,048 |  | 12,875
With a related allowance recorded, Average Recorded Investment | 24 | 29 | 11,514 | 11,089 |
With a related allowance recorded, Interest Income Recognized | 1 | 1 | 255 | 243 |
Without a related allowance recorded, Average Recorded Investment | 11,280 | 11,028 | 25 | 30 |
Without a related allowance recorded, Interest Income Recognized | 125 | 107 | 1 | 1 |
Impaired Financing Receivable, Average Recorded Investment, Total | 11,304 | 11,057 | 11,539 | 11,119 |
Impaired Financing Receivable, Interest Income Recognized, Total | 126 | 108 | 256 | 244 |
Other Consumer |  |  |  |  |
Financing Receivable, Impaired [Line Items] |  |  |  |  |
With a related allowance recorded, Recorded Investment | 25 |  | 25 |  | 1
With a related allowance recorded, Unpaid Principal Balance | 25 |  | 25 |  | 1
Impaired Financing Receivable, Related Allowance | 25 |  | 25 |  | 1
Without a related allowance recorded, Recorded Investment | 10 |  | 10 |  | 24
Without a related allowance, Unpaid Principal Balance | 13 |  | 13 |  | 31
Without a related allowance recorded, Related Allowance | 0 |  | 0 |  | 0
Impaired Financing Receivable, Recorded Investment | 35 |  | 35 |  | 25
Impaired Financing Receivable, Unpaid Principal Balance, Total | 38 |  | 38 |  | $ 32
With a related allowance recorded, Average Recorded Investment | 26 | 1 | 12 | 40 |
With a related allowance recorded, Interest Income Recognized | 0 | 0 | 0 | 1 |
Without a related allowance recorded, Average Recorded Investment | 11 | 38 | 27 | 2 |
Without a related allowance recorded, Interest Income Recognized | 1 | 0 | 1 | 0 |
Impaired Financing Receivable, Average Recorded Investment, Total | 37 | 39 | 39 | 42 |
Impaired Financing Receivable, Interest Income Recognized, Total | $ 1 | $ 0 | $ 1 | $ 1 |

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