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Acquisition - Summary of Acquisition Related Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Business Acquisition [Line Items]
Data processing	$ 950	$ 946	$ 3,354	$ 2,848
Professional services	727	801	2,836	1,845
Other expense	1,628	1,471	4,989	4,716
Bank of Napa, N.A. (Napa)
Business Acquisition [Line Items]
Data processing	43	0	598	0
Professional services	46	449	172	458
Personnel severance	0	0	141	0
Other expense	0	46	43	46
Total	$ 89	$ 495	$ 954	$ 504

X

- Definition

The amount of expenses incurred in the period for data processing products and services.

+ References

No definition available.

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- Definition

Personnel Severance

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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.

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
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- Definition

Amount of noninterest expense classified as other.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
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- Definition

A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

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-Name Accounting Standards Codification
-Topic 946
-SubTopic 220
-Section S99
-Paragraph 1
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