XML 89 R76.htm IDEA: XBRL DOCUMENT
v3.22.0.1

Loans (Interest written off on nonaccrual loans) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Financing Receivable, Credit Quality Indicator - narrative [Line Items] |  |  |
Interest written off on nonaccrual loans | $ 673 | $ 2,000 | $ 1,671
Commercial Portfolio Segment |  |  |
Financing Receivable, Credit Quality Indicator - narrative [Line Items] |  |  |
Interest written off on nonaccrual loans | 628 | 1,972 | 1,475
Consumer |  |  |
Financing Receivable, Credit Quality Indicator - narrative [Line Items] |  |  |
Interest written off on nonaccrual loans | $ 45 | $ 28 | $ 196

X
- Definition Financing Receivable Accrued Interest Reversed Through Interest Income + References No definition available. + Details
Name: | colb_FinancingReceivableAccruedInterestReversedThroughInterestIncome
Namespace Prefix: | colb_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- 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
Name: | us-gaap_FinancingReceivableRecordedInvestmentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |