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Acquisition - Narrative (Details) |  |  | 12 Months Ended
--- | --- | --- | ---
Nov. 21, 2017 USD ($) branch | Nov. 29, 2013 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Business Acquisition [Line Items] |  |  |  |
Goodwill |  |  | $ 30,140,000 | $ 30,140,000
Amortization of core deposit intangible |  |  | 921,000 | 529,000
Bank of Napa, N.A. (Napa) |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Number of branch offices | branch | 2 |  |  |
Loans acquired | $ 134,700,000 |  |  |
Deposits assumed | 249,900,000 |  |  |
Investment securities acquired | $ 75,500,000 |  |  |
Shares received by Napa shareholders in merger per acquiree share | 0.307 |  |  |
Goodwill | $ 23,700,000 |  |  |
Goodwill impairment |  |  | 0 | 0
NorCal Community Bancorp |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Goodwill |  | $ 6,400,000 |  |
Core deposit intangible |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Core deposit intangible asset |  |  | $ 5,571,000 |
Useful life of core deposit intangible asset |  |  | 10 years |
Core deposit intangible | Bank of Napa, N.A. (Napa) |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Core deposit intangible asset | $ 4,400,000 |  |  |
Amortization of core deposit intangible |  |  | $ 508,000 | $ 56,000
Useful life of core deposit intangible asset | 10 years |  |  |
Core deposit intangible | NorCal Community Bancorp |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Core deposit intangible asset |  | $ 4,600,000 |  |
Useful life of core deposit intangible asset |  | 10 years |  |

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- Definition Business Combination, Consideration Transferred, Equity Interests Issued and Issuable, Entity Shares Issued Per Acquiree Share, Ratio + References No definition available. + Details
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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 + Details
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- Definition Amount of investments in debt and equity securities, including, but not limited to, held-to-maturity, trading and available-for-sale expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details
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- Definition Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details
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- Definition The amount of financial liabilities assumed (as defined) which have been recognized as of the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 55 -Paragraph 37 -URI http://asc.fasb.org/extlink&oid=108330185&loc=d3e2207-128464 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details
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