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Loans and Allowance for Loan Losses - Purchased Credit-Impaired Loans (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
PCI Loans, Carrying Value [Abstract] |  |  |
Unpaid principal balance | $ 3,350 | $ 4,977 |
Carrying value | 2,920 | 3,681 |
Increase of specific allowance for PCI loan losses |  | 4 | $ 3
Decrease in allowance for loan losses for PCI loans | 6 | 2 | 238
Accretable Yield [Roll Forward] |  |  |
Balance at beginning of period | 2,618 | 4,027 | 3,649
Additions | 0 | 0 | 0
Removals | (778) | (914) | (273)
Accretion | (364) | (495) | (613)
Reclassifications from nonaccretable difference | 0 | 0 | 1,264
Balance at end of period | 1,476 | 2,618 | $ 4,027
Commercial loans | Commercial and industrial |  |  |
PCI Loans, Carrying Value [Abstract] |  |  |
Unpaid principal balance | 45 | 237 |
Carrying value | 40 | 175 |
Commercial real estate loans | Commercial real estate, owner-occupied |  |  |
PCI Loans, Carrying Value [Abstract] |  |  |
Unpaid principal balance | 1,344 | 2,573 |
Carrying value | 1,072 | 1,711 |
Commercial real estate loans | Commercial real estate, investor |  |  |
PCI Loans, Carrying Value [Abstract] |  |  |
Unpaid principal balance | 1,713 | 1,756 |
Carrying value | 1,706 | 1,726 |
Commercial real estate loans | Construction |  |  |
PCI Loans, Carrying Value [Abstract] |  |  |
Unpaid principal balance | 0 | 187 |
Carrying value | 0 | 1 |
Residential loans | Home equity |  |  |
PCI Loans, Carrying Value [Abstract] |  |  |
Unpaid principal balance | 248 | 224 |
Carrying value | $ 102 | $ 68 |

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- Definition Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538 + Details
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- Definition Amount of accretion recognized for the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities, with evidence of deterioration of credit quality. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 + Details
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- Definition Amount of additions to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 + Details
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- Definition Amount of reduction, resulting from a sale or transfer of a loan, in the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538 + Details
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- Definition Amount of increase of reclassification from nonaccretable difference to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 + Details
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- Definition Amount of reduction in the reserve for loans impairments as a result of current information and events which result in it being probable that estimated cash flows will be significantly higher than previously expected or because actual cash flows are significantly greater than cash flows previously expected for loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References No definition available. + Details
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- Definition The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538 + Details
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- Definition The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 + Details
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