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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 | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015
Financing Receivable, Impaired [Line Items] |  |
With a related allowance recorded, Recorded Investment | $ 991 | $ 618
With a related allowance recorded, Unpaid Principal Balance | 2,460 | 1,468
With a related allowance recorded, Related Allowance | 798 | 37
Without a related allowance recorded, Recorded Investment | 40,944 | 45,032
Without a related allowance, Unpaid Principal Balance | 48,539 | 50,286
Without a related allowance recorded, Related Allowance | 0 | 0
Impaired financing receivables | 41,935 | 45,650
Impaired Financing Receivable, Unpaid Principal Balance, Total | 50,999 | 51,754
Impaired Financing Receivable, Related Allowance, Total | 798 | 37
Without a related allowance recorded, Average Recorded Investment | 43,334 | 46,638
Without a related allowance recorded, Interest Income Recognized | 990 | 1,741
With a related allowance recorded, Average Recorded Investment | 2,468 | 956
With a related allowance recorded, Interest Income Recognized | 2 | 7
Impaired Financing Receivable, Average Recorded Investment, Total | 45,802 | 47,594
Impaired Financing Receivable, Interest Income Recognized, Total | 992 | 1,748
Commercial Real Estate |  |
Financing Receivable, Impaired [Line Items] |  |
With a related allowance recorded, Recorded Investment | 0 | 0
With a related allowance recorded, Unpaid Principal Balance | 0 | 0
With a related allowance recorded, Related Allowance | 0 | 0
Without a related allowance recorded, Recorded Investment | 16,352 | 12,661
Without a related allowance, Unpaid Principal Balance | 17,654 | 13,157
Without a related allowance recorded, Related Allowance | 0 | 0
Impaired financing receivables | 16,352 | 12,661
Impaired Financing Receivable, Unpaid Principal Balance, Total | 17,654 | 13,157
Impaired Financing Receivable, Related Allowance, Total | 0 | 0
Without a related allowance recorded, Average Recorded Investment | 17,496 | 14,622
Without a related allowance recorded, Interest Income Recognized | 144 | 597
With a related allowance recorded, Average Recorded Investment | 0 | 0
With a related allowance recorded, Interest Income Recognized | 0 | 0
Impaired Financing Receivable, Average Recorded Investment, Total | 17,496 | 14,622
Impaired Financing Receivable, Interest Income Recognized, Total | 144 | 597
Commercial and Industrial |  |
Financing Receivable, Impaired [Line Items] |  |
With a related allowance recorded, Recorded Investment | 964 | 0
With a related allowance recorded, Unpaid Principal Balance | 2,433 | 0
With a related allowance recorded, Related Allowance | 771 | 0
Without a related allowance recorded, Recorded Investment | 5,902 | 14,417
Without a related allowance, Unpaid Principal Balance | 7,699 | 15,220
Without a related allowance recorded, Related Allowance | 0 | 0
Impaired financing receivables | 6,866 | 14,417
Impaired Financing Receivable, Unpaid Principal Balance, Total | 10,132 | 15,220
Impaired Financing Receivable, Related Allowance, Total | 771 | 0
Without a related allowance recorded, Average Recorded Investment | 6,141 | 14,416
Without a related allowance recorded, Interest Income Recognized | 160 | 450
With a related allowance recorded, Average Recorded Investment | 2,438 | 0
With a related allowance recorded, Interest Income Recognized | 0 | 0
Impaired Financing Receivable, Average Recorded Investment, Total | 8,579 | 14,416
Impaired Financing Receivable, Interest Income Recognized, Total | 160 | 450
Commercial Construction |  |
Financing Receivable, Impaired [Line Items] |  |
With a related allowance recorded, Recorded Investment | 0 | 500
With a related allowance recorded, Unpaid Principal Balance | 0 | 1,350
With a related allowance recorded, Related Allowance | 0 | 3
Without a related allowance recorded, Recorded Investment | 6,613 | 10,998
Without a related allowance, Unpaid Principal Balance | 10,306 | 14,200
Without a related allowance recorded, Related Allowance | 0 | 0
Impaired financing receivables | 6,613 | 11,498
Impaired Financing Receivable, Unpaid Principal Balance, Total | 10,306 | 15,550
Impaired Financing Receivable, Related Allowance, Total | 0 | 3
Without a related allowance recorded, Average Recorded Investment | 7,723 | 10,581
Without a related allowance recorded, Interest Income Recognized | 162 | 329
With a related allowance recorded, Average Recorded Investment | 0 | 834
With a related allowance recorded, Interest Income Recognized | 0 | 0
Impaired Financing Receivable, Average Recorded Investment, Total | 7,723 | 11,415
Impaired Financing Receivable, Interest Income Recognized, Total | 162 | 329
Consumer Real Estate |  |
Financing Receivable, Impaired [Line Items] |  |
With a related allowance recorded, Recorded Investment | 26 | 116
With a related allowance recorded, Unpaid Principal Balance | 26 | 116
With a related allowance recorded, Related Allowance | 26 | 32
Without a related allowance recorded, Recorded Investment | 12,053 | 6,845
Without a related allowance, Unpaid Principal Balance | 12,849 | 7,521
Without a related allowance recorded, Related Allowance | 0 | 0
Impaired financing receivables | 12,079 | 6,961
Impaired Financing Receivable, Unpaid Principal Balance, Total | 12,875 | 7,637
Impaired Financing Receivable, Related Allowance, Total | 26 | 32
Without a related allowance recorded, Average Recorded Investment | 11,939 | 6,902
Without a related allowance recorded, Interest Income Recognized | 523 | 364
With a related allowance recorded, Average Recorded Investment | 28 | 120
With a related allowance recorded, Interest Income Recognized | 2 | 7
Impaired Financing Receivable, Average Recorded Investment, Total | 11,967 | 7,022
Impaired Financing Receivable, Interest Income Recognized, Total | 525 | 371
Other Consumer |  |
Financing Receivable, Impaired [Line Items] |  |
With a related allowance recorded, Recorded Investment | 1 | 2
With a related allowance recorded, Unpaid Principal Balance | 1 | 2
With a related allowance recorded, Related Allowance | 1 | 2
Without a related allowance recorded, Recorded Investment | 24 | 111
Without a related allowance, Unpaid Principal Balance | 31 | 188
Without a related allowance recorded, Related Allowance | 0 | 0
Impaired financing receivables | 25 | 113
Impaired Financing Receivable, Unpaid Principal Balance, Total | 32 | 190
Impaired Financing Receivable, Related Allowance, Total | 1 | 2
Without a related allowance recorded, Average Recorded Investment | 35 | 117
Without a related allowance recorded, Interest Income Recognized | 1 | 1
With a related allowance recorded, Average Recorded Investment | 2 | 2
With a related allowance recorded, Interest Income Recognized | 0 | 0
Impaired Financing Receivable, Average Recorded Investment, Total | 37 | 119
Impaired Financing Receivable, Interest Income Recognized, Total | $ 1 | $ 1

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