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Securities Sold Under Agreements to Repurchase (Details) - Repurchase Agreements, Sweep $ in Millions | Dec. 31, 2021 USD ($)
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Assets Sold under Agreements to Repurchase [Line Items] |
Carrying amount of securities pledged as collateral | $ 101.1
Available-for-sale Securities |
Assets Sold under Agreements to Repurchase [Line Items] |
Assets Sold under Agreements to Repurchase, Sweep, Carrying Amount | $ 86.0
Assets Sold under Agreements to Repurchase, Sweep, Interest rate | 0.18%

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- Definition Carrying amount of assets sold under agreements to repurchase related to sweep products when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under repurchase agreements exceeds 10 percent of total assets. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Interest rate on the amount to be repaid to the counterparty to the sweep product repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets. + References No definition available. + Details
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Namespace Prefix: | colb_
Data Type: | dtr-types:percentItemType
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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. + References No definition available. + Details
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- Definition The carrying amount as of the date of the latest financial statement presented of securities which are owned but transferred to serve as collateral for repurchase agreements, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b)(1)(i) -URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729 + Details
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Balance Type: | debit
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- Details
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- Details
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Balance Type: |
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