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Revolving Line of Credit | 9 Months Ended
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Sep. 30, 2019
Line of Credit [Member] |
Line of Credit Facility [Line Items] |
Short-term Debt [Text Block] | Revolving Line of Credit During the second quarter of 2019, the Company entered into a $30.0 million short-term credit facility with an unaffiliated bank that matures in May 2020. This facility has a variable interest rate and provides the Company additional liquidity, if needed, for various corporate activities including the repurchase of shares of Columbia Banking System, Inc. common stock. As of September 30, 2019 and December 31, 2018, there was no outstanding balance. The credit agreement requires the Company to comply with certain covenants including those related to asset quality and capital levels. The Company was in compliance with all covenants associated with this facility at September 30, 2019.

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- Definition The entire disclosure for short-term debt. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -URI http://asc.fasb.org/topic&trid=2208564 + Details
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