XML 81 R76.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Loans Loans, analysis of purchased credit impaired loans (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | --- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Allowance | $ 83,968 | $ 83,369 | $ 75,646 | $ 70,043
Loans and Leases Receivable, Net Amount | 8,659,497 | 8,308,142 |  |
Commercial Portfolio Segment [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 3,610,460 | 3,447,662 |  |
Real estate: One-to-four family residential [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 272,347 | 246,384 |  |
Loans and Leases Receivable, Allowance | 607 | 593 | 701 | 599
Commercial and Multifamily Residential [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 4,238,173 | 3,908,937 |  |
Real Estate Portfolio Segment [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 4,510,520 | 4,155,321 |  |
One-to-Four Family Residential Construction [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 192,762 | 217,943 |  |
Commercial and Multifamily Residential Construction [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 163,103 | 284,928 |  |
Real Estate Construction Portfolio Segment [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 355,865 | 502,871 |  |
Consumer [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 300,935 | 327,851 |  |
Loans and Leases Receivable, Allowance | 4,455 | 5,301 | $ 5,163 | $ 3,534
Purchased Credit Impaired Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 82,272 | 96,285 |  |
Valuation discount resulting from acquisition accounting | 4,756 | 6,525 |  |
Loans and Leases Receivable, Allowance | 2,844 | 3,611 |  |
Loans and Leases Receivable, Net Amount | 74,672 | 86,149 |  |
Purchased Credit Impaired Loans [Member] | Commercial Portfolio Segment [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 8,083 | 9,672 |  |
Purchased Credit Impaired Loans [Member] | Real estate: One-to-four family residential [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 8,453 | 9,848 |  |
Purchased Credit Impaired Loans [Member] | Commercial and Multifamily Residential [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 56,752 | 66,340 |  |
Purchased Credit Impaired Loans [Member] | Real Estate Portfolio Segment [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 65,205 | 76,188 |  |
Purchased Credit Impaired Loans [Member] | One-to-Four Family Residential Construction [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 0 | 153 |  |
Purchased Credit Impaired Loans [Member] | Commercial and Multifamily Residential Construction [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 0 | 507 |  |
Purchased Credit Impaired Loans [Member] | Real Estate Construction Portfolio Segment [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | 0 | 660 |  |
Purchased Credit Impaired Loans [Member] | Consumer [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount | $ 8,984 | $ 9,765 |  |

X
- Definition Acquisition Accounting Valuation Discount on Covered Loans + References No definition available. + Details
Name: | colb_AcquisitionAccountingValuationDiscountOnCoveredLoans
Namespace Prefix: | colb_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.1) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707 + Details
Name: | us-gaap_LoansAndLeasesReceivableAllowance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522 + Details
Name: | us-gaap_LoansAndLeasesReceivableGrossCarryingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
Name: | us-gaap_LoansAndLeasesReceivableNetReportedAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

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

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

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

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

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

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=colb_RealEstateConstructionPortfolioSegmentMember
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: |

X
- Details
Name: | colb_LoansByMajorCategoryAxis=colb_PurchasedCreditImpairedLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |