Significant Accounting Policies (Policies)	6 Months Ended
Jun. 30, 2021
Accounting Policies [Abstract]
Consolidation, Policy [Policy Text Block]	Principles of Consolidation The accompanying consolidated financial statements include the accounts of the Holding Company and its subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. As of June 30, 2021 and December 31, 2020, the Company had one wholly-owned trust formed in 2005 to issue trust preferred securities and related common securities. We have not consolidated the accounts of the Trust in our consolidated financial statements in accordance with Financial Accounting Standards Board Accounting Standards Codification (“FASB”), Consolidation (“ASC 810”). We are not considered the primary beneficiary of the Trust (variable interest entity). As a result, the junior subordinated debentures issued by the Holding Company to the Trust are reflected on the Company’s Consolidated Balance Sheets.
Loans and Leases Receivable, Allowance for Loan Losses Policy [Policy Text Block]	Allowance for Credit Losses In June 2016, the FASB issued Accounting Standards Update (“ASU”) 2016-13, Measurement of Credit Losses on Financial Instruments. The ASU introduces a new impairment model based on current expected credit losses (“CECL”) in substitution for our current “incurred loss” methodology. Amendments to ASU 2016-13 permit us to delay implementation of CECL until January 1, 2023. As discussed in Note 11 Merger in the Notes to Consolidated Financial Statements, the Company has entered into an Agreement and Plan of Merger with Columbia Banking System, Inc. with Columbia as the surviving entity. The transaction is expected to close during the fourth quarter of 2021; therefore, we do not anticipate adopting ASU No. 2016-13.
Lessee, Leases [Policy Text Block]	Leases We determine if an arrangement is a lease at inception. Operating leases are included in Other Assets and Other Liabilities in our Consolidated Balance Sheets. Operating lease right-of-use assets and operating lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term at commencement date. As most of our leases do not provide an incremental borrowing rate, we use borrowing rates available under our existing line of credit with the FHLB for periods similar to the lease terms as our incremental borrowing rate to determine the present value of future lease payments. Our lease terms may include options to extend or terminate the lease which we recognize when it is reasonably certain that we will exercise that option. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term.

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- Definition

Disclosure of accounting policy regarding (1) the principles it follows in consolidating or combining the separate financial statements, including the principles followed in determining the inclusion or exclusion of subsidiaries or other entities in the consolidated or combined financial statements and (2) its treatment of interests (for example, common stock, a partnership interest or other means of exerting influence) in other entities, for example consolidation or use of the equity or cost methods of accounting. The accounting policy may also address the accounting treatment for intercompany accounts and transactions, noncontrolling interest, and the income statement treatment in consolidation for issuances of stock by a subsidiary.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123372394&loc=d3e18823-107790

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=109239629&loc=d3e5614-111684

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- Definition

Disclosure of accounting policy for leasing arrangement entered into by lessee.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918666-209980

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- Definition

Disclosure of accounting policy for estimating the allowance for losses on loans and lease receivables. The disclosure may include (a) how the entity determines each element of the allowance, (b) which loans are evaluated individually and which loans are evaluated as a group, (c) how the entity determines both the allocated and unallocated portions of the allowance, (d) how the entity determines the loss factors applied to graded loans in order to develop a general allowance, and (e) what self-correcting mechanism the entity uses to reduce differences between estimated and actual losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5144-111524

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