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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, 2017 | Mar. 31, 2016 | Dec. 31, 2016
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment | $ 9,955 |  | $ 991
With a related allowance recorded, Unpaid Principal Balance | 11,546 |  | 2,460
Impaired Financing Receivable, Related Allowance | 3,567 |  | 798
Without a related allowance recorded, Recorded Investment | 36,803 |  | 40,944
Without a related allowance, Unpaid Principal Balance | 43,405 |  | 48,539
Without a related allowance recorded, Related Allowance | 0 |  | 0
Impaired Financing Receivable, Recorded Investment | 46,758 |  | 41,935
Impaired Financing Receivable, Unpaid Principal Balance, Total | 54,951 |  | 50,999
With a related allowance recorded, Average Recorded Investment | 10,035 | $ 6,616 |
With a related allowance recorded, Interest Income Recognized | 72 | 40 |
Without a related allowance recorded, Average Recorded Investment | 37,944 | 56,028 |
Without a related allowance recorded, Interest Income Recognized | 242 | 547 |
Impaired Financing Receivable, Average Recorded Investment, Total | 47,979 | 62,644 |
Impaired Financing Receivable, Interest Income Recognized, Total | 314 | 587 |
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
Impaired Financing Receivable, Related Allowance | 0 |  | 0
Without a related allowance recorded, Recorded Investment | 8,429 |  | 16,352
Without a related allowance, Unpaid Principal Balance | 9,773 |  | 17,654
Without a related allowance recorded, Related Allowance | 0 |  | 0
Impaired Financing Receivable, Recorded Investment | 8,429 |  | 16,352
Impaired Financing Receivable, Unpaid Principal Balance, Total | 9,773 |  | 17,654
With a related allowance recorded, Average Recorded Investment | 0 | 0 |
With a related allowance recorded, Interest Income Recognized | 0 | 0 |
Without a related allowance recorded, Average Recorded Investment | 8,581 | 18,605 |
Without a related allowance recorded, Interest Income Recognized | 33 | 199 |
Impaired Financing Receivable, Average Recorded Investment, Total | 8,581 | 18,605 |
Impaired Financing Receivable, Interest Income Recognized, Total | 33 | 199 |
Commercial And Industrial |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment | 9,929 |  | 964
With a related allowance recorded, Unpaid Principal Balance | 11,520 |  | 2,433
Impaired Financing Receivable, Related Allowance | 3,541 |  | 771
Without a related allowance recorded, Recorded Investment | 11,115 |  | 5,902
Without a related allowance, Unpaid Principal Balance | 11,651 |  | 7,699
Without a related allowance recorded, Related Allowance | 0 |  | 0
Impaired Financing Receivable, Recorded Investment | 21,044 |  | 6,866
Impaired Financing Receivable, Unpaid Principal Balance, Total | 23,171 |  | 10,132
With a related allowance recorded, Average Recorded Investment | 10,008 | 5,382 |
With a related allowance recorded, Interest Income Recognized | 72 | 32 |
Without a related allowance recorded, Average Recorded Investment | 11,410 | 15,513 |
Without a related allowance recorded, Interest Income Recognized | 43 | 149 |
Impaired Financing Receivable, Average Recorded Investment, Total | 21,418 | 20,895 |
Impaired Financing Receivable, Interest Income Recognized, Total | 115 | 181 |
Commercial Construction |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment | 0 |  |
With a related allowance recorded, Unpaid Principal Balance | 0 |  |
Impaired Financing Receivable, Related Allowance | 0 |  |
Without a related allowance recorded, Recorded Investment | 5,903 |  | 6,613
Without a related allowance, Unpaid Principal Balance | 9,773 |  | 10,306
Without a related allowance recorded, Related Allowance | 0 |  | 0
Impaired Financing Receivable, Recorded Investment | 5,903 |  | 6,613
Impaired Financing Receivable, Unpaid Principal Balance, Total | 9,773 |  | 10,306
With a related allowance recorded, Average Recorded Investment | 0 | 1,117 |
With a related allowance recorded, Interest Income Recognized | 0 | 6 |
Without a related allowance recorded, Average Recorded Investment | 6,239 | 10,782 |
Without a related allowance recorded, Interest Income Recognized | 37 | 64 |
Impaired Financing Receivable, Average Recorded Investment, Total | 6,239 | 11,899 |
Impaired Financing Receivable, Interest Income Recognized, Total | 37 | 70 |
Consumer Real Estate |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment | 25 |  | 26
With a related allowance recorded, Unpaid Principal Balance | 25 |  | 26
Impaired Financing Receivable, Related Allowance | 25 |  | 26
Without a related allowance recorded, Recorded Investment | 11,335 |  | 12,053
Without a related allowance, Unpaid Principal Balance | 12,185 |  | 12,849
Without a related allowance recorded, Related Allowance | 0 |  | 0
Impaired Financing Receivable, Recorded Investment | 11,360 |  | 12,079
Impaired Financing Receivable, Unpaid Principal Balance, Total | 12,210 |  | 12,875
With a related allowance recorded, Average Recorded Investment | 26 | 115 |
With a related allowance recorded, Interest Income Recognized | 0 | 2 |
Without a related allowance recorded, Average Recorded Investment | 11,692 | 11,102 |
Without a related allowance recorded, Interest Income Recognized | 129 | 135 |
Impaired Financing Receivable, Average Recorded Investment, Total | 11,718 | 11,217 |
Impaired Financing Receivable, Interest Income Recognized, Total | 129 | 137 |
Other Consumer |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
With a related allowance recorded, Recorded Investment | 1 |  | 1
With a related allowance recorded, Unpaid Principal Balance | 1 |  | 1
Impaired Financing Receivable, Related Allowance | 1 |  | 1
Without a related allowance recorded, Recorded Investment | 21 |  | 24
Without a related allowance, Unpaid Principal Balance | 23 |  | 31
Without a related allowance recorded, Related Allowance | 0 |  | 0
Impaired Financing Receivable, Recorded Investment | 22 |  | 25
Impaired Financing Receivable, Unpaid Principal Balance, Total | 24 |  | $ 32
With a related allowance recorded, Average Recorded Investment | 1 | 2 |
With a related allowance recorded, Interest Income Recognized | 0 | 0 |
Without a related allowance recorded, Average Recorded Investment | 22 | 26 |
Without a related allowance recorded, Interest Income Recognized | 0 | 0 |
Impaired Financing Receivable, Average Recorded Investment, Total | 23 | 28 |
Impaired Financing Receivable, Interest Income Recognized, Total | $ 0 | $ 0 |

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- Definition Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524 + Details
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