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Acquisition - Outstanding Balance and Related Carrying Value of PCI Loans (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Nov. 21, 2017 | Dec. 31, 2016
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Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items] |  |  |
Unpaid Principal Balance | $ 2,868 |  | $ 3,350
Bank of Napa, N.A. (Napa) | Receivables Acquired with Deteriorated Credit Quality |  |  |
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items] |  |  |
Unpaid Principal Balance |  | $ 1,487 |
Fair value |  | 855 |
Bank of Napa, N.A. (Napa) | Commercial | Receivables Acquired with Deteriorated Credit Quality |  |  |
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items] |  |  |
Unpaid Principal Balance |  | 417 |
Fair value |  | 70 |
Bank of Napa, N.A. (Napa) | Commercial real estate | Receivables Acquired with Deteriorated Credit Quality |  |  |
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items] |  |  |
Unpaid Principal Balance |  | 1,070 |
Fair value |  | $ 785 |

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- Definition Fair value at acquisition of acquired loans 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=82894507&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)(3) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + 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=82894507&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=82894903&loc=d3e15032-111544 + Details
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