Mergers and Acquisitions - Acquisition Related Expenses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Business Acquisition [Line Items]
Total merger and integration expenses	$ 947	$ 1,207
Merger and Integration Expense
Business Acquisition [Line Items]
Total merger and integration expenses	947	1,207
Merger and Integration Expense \| Wilshire
Business Acquisition [Line Items]
Total merger and integration expenses	401	1,183
Merger and Integration Expense \| U & I Financial Corp [Member]
Business Acquisition [Line Items]
Total merger and integration expenses	522	0
Merger and Integration Expense \| Other
Business Acquisition [Line Items]
Total merger and integration expenses	$ 24	$ 24

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.

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=73531572&loc=d3e1043-128460

Name:	us-gaap_BusinessCombinationAcquisitionRelatedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration