v3.8.0.1

Acquisitions - Additional information (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Nov. 10, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Deferred income tax asset, operating loss carry-forward and other tax attributes		$ 3,157	$ 3,896
Community 1st Bancorp
Business Acquisition [Line Items]
Acquisition date	Nov. 10, 2017
Common stock issued in exchange for acquisition, shares	2,955,623
Stock value per share, acquisition date	$ 17.55
Goodwill	$ 26,000
Deferred income tax asset, operating loss carry-forward and other tax attributes		$ 600
Business combination, value of deposit	$ 5,800
Finite-lived intangible asset, amortized period		7 years
Business combination, pro forma information, revenue of acquiree since acquisition date, actual		$ 1,400
Business combination, pro forma information, earnings or loss of acquiree since acquisition date, actual		$ 900
Pacific Rim Bank
Business Acquisition [Line Items]
Acquisition date		Jan. 01, 2017	Jan. 01, 2016	Jan. 01, 2015
Decrease in net income, pro forma adjustment		$ 500	$ 700	$ 300
Business combination, pro forma information, revenue of acquiree since acquisition date, actual				2,500
Business combination, pro forma information, earnings or loss of acquiree since acquisition date, actual				$ 800

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- Definition

Business acquisition pro forma information adjustments.

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- Definition

Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

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- Definition

Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e845-128460

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

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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.

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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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