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Acquisition - Acquisition Related Costs (Details) - NorCal Community Bancorp - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Acquisition related expenses	$ 746	$ 3,744
Data processing
Business Acquisition [Line Items]
Acquisition related expenses	442	2,807
Professional services
Business Acquisition [Line Items]
Acquisition related expenses	0	660
Personnel severance
Business Acquisition [Line Items]
Acquisition related expenses	304	203
Other
Business Acquisition [Line Items]
Acquisition related expenses	$ 0	$ 74

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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

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e1043-128460

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