XML 95 R80.htm IDEA: XBRL DOCUMENT
v3.6.0.2

FDIC Loss-sharing Asset and Covered Assets (Narrative) (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Covered Assets And FDIC Loss Sharing Asset [Line Items] |  |  |  |  |  |  |  |  |  |  |
Payment Of Clawback If Losses Less Than Stated Levels, Period After Acquisition |  |  |  |  |  |  |  |  | 10 years 45 days |  |
Amount of estimated clawback liability | $ 5,433 |  |  |  | $ 5,200 |  |  |  | $ 5,433 | $ 5,200 |
Provision for loan and lease losses | 18 | $ 1,866 | $ 3,640 | $ 5,254 | 2,349 | $ 2,831 | $ 2,202 | $ 1,209 | 10,778 | 8,591 | $ 6,727
Federal deposit insurance corporation loss-sharing indemnified assets | 2,700 |  |  |  | 6,000 |  |  |  | 2,700 | 6,000 |
Federal deposit insurance corporation loss-sharing indemnified assets receivable | 794 |  |  |  | 605 |  |  |  | 794 | 605 |
FDIC Indemnification Asset | 3,535 |  |  |  | 6,568 |  |  |  | 3,535 | 6,568 |
FDIC Loss-sharing Asset, Write-downs of Other Real Estate |  |  |  |  |  |  |  |  | (22) | 1,158 |
Non-Single Family Covered Assets | 83,179 |  |  |  |  |  |  |  | 83,179 |  |
Single Family Covered Assets | $ 30,506 |  |  |  |  |  |  |  | $ 30,506 |  |
Maximum [Member] |  |  |  |  |  |  |  |  |  |  |
Covered Assets And FDIC Loss Sharing Asset [Line Items] |  |  |  |  |  |  |  |  |  |  |
Loss Recovery Provision Effective Years |  |  |  |  |  |  |  |  | 10 years |  |
Loss Sharing Agreement Effective Years |  |  |  |  |  |  |  |  | 10 years |  |
Minimum [Member] |  |  |  |  |  |  |  |  |  |  |
Covered Assets And FDIC Loss Sharing Asset [Line Items] |  |  |  |  |  |  |  |  |  |  |
Loss Recovery Provision Effective Years |  |  |  |  |  |  |  |  | 8 years |  |
Loss Sharing Agreement Effective Years |  |  |  |  |  |  |  |  | 5 years |  |
Covered Loans [Member] |  |  |  |  |  |  |  |  |  |  |
Covered Assets And FDIC Loss Sharing Asset [Line Items] |  |  |  |  |  |  |  |  |  |  |
Percentage of loss shared by FDIC When Loss Share Thresholds Met | 95.00% |  |  |  |  |  |  |  | 95.00% |  |
FDIC Percentage Of Loss Recoveries When Loss Share Thresholds Met | 95.00% |  |  |  |  |  |  |  | 95.00% |  |
Percentage of loss shared by FDIC | 80.00% |  |  |  |  |  |  |  | 80.00% |  |
FDIC Percentage Of Loss Recoveries | 80.00% |  |  |  |  |  |  |  | 80.00% |  |
Fdic Loss Sharing Asset [Member] |  |  |  |  |  |  |  |  |  |  |
Covered Assets And FDIC Loss Sharing Asset [Line Items] |  |  |  |  |  |  |  |  |  |  |
FDIC Indemnification Asset | $ 3,535 |  |  |  | $ 6,568 |  |  |  | $ 3,535 | 6,568 | $ 15,174
FDIC Loss-sharing Asset, Cash Payments Received |  |  |  |  |  |  |  |  | (705) | 2,794 |
FDIC Loss-sharing Asset, Net Reimbursable Losses |  |  |  |  |  |  |  |  | (1,153) | (1,802) |
FDIC Loss-sharing Asset, Amortization, Net |  |  |  |  |  |  |  |  | (2,829) | (6,184) |
FDIC Loss-sharing Asset, Impairment (Recapture) of Loans |  |  |  |  |  |  |  |  | 301 | 2,268 |
FDIC Loss-sharing Asset, Disposals |  |  |  |  |  |  |  |  | (148) | 1,237 |
FDIC Loss-sharing Asset, Other |  |  |  |  |  |  |  |  | (183) | $ (15) |
Columbia River Bank [Member] |  |  |  |  |  |  |  |  |  |  |
Covered Assets And FDIC Loss Sharing Asset [Line Items] |  |  |  |  |  |  |  |  |  |  |
Amount of estimated clawback liability | 3,433 |  |  |  |  |  |  |  | 3,433 |  |
FDIC Indemnification Asset | 101 |  |  |  |  |  |  |  | 101 |  |
Non-Single Family Covered Assets | 57,017 |  |  |  |  |  |  |  | 57,017 |  |
Single Family Covered Assets | 6,121 |  |  |  |  |  |  |  | 6,121 |  |
American Marine Bank [Member] |  |  |  |  |  |  |  |  |  |  |
Covered Assets And FDIC Loss Sharing Asset [Line Items] |  |  |  |  |  |  |  |  |  |  |
Amount of estimated clawback liability | 1,269 |  |  |  |  |  |  |  | 1,269 |  |
FDIC Indemnification Asset | 1,866 |  |  |  |  |  |  |  | 1,866 |  |
Non-Single Family Covered Assets | 9,059 |  |  |  |  |  |  |  | 9,059 |  |
Single Family Covered Assets | 18,517 |  |  |  |  |  |  |  | 18,517 |  |
Summit Bank [Member] |  |  |  |  |  |  |  |  |  |  |
Covered Assets And FDIC Loss Sharing Asset [Line Items] |  |  |  |  |  |  |  |  |  |  |
Amount of estimated clawback liability | 0 |  |  |  |  |  |  |  | 0 |  |
FDIC Indemnification Asset | 1,426 |  |  |  |  |  |  |  | 1,426 |  |
Non-Single Family Covered Assets | 5,066 |  |  |  |  |  |  |  | 5,066 |  |
Single Family Covered Assets | 4,420 |  |  |  |  |  |  |  | 4,420 |  |
First Heritage Bank [Member] |  |  |  |  |  |  |  |  |  |  |
Covered Assets And FDIC Loss Sharing Asset [Line Items] |  |  |  |  |  |  |  |  |  |  |
Amount of estimated clawback liability | 731 |  |  |  |  |  |  |  | 731 |  |
FDIC Indemnification Asset | 142 |  |  |  |  |  |  |  | 142 |  |
Non-Single Family Covered Assets | 12,037 |  |  |  |  |  |  |  | 12,037 |  |
Single Family Covered Assets | $ 1,448 |  |  |  |  |  |  |  | $ 1,448 |  |

X
- Definition Amount of estimated clawback liability + References No definition available. + Details
Name: | colb_AmountOfEstimatedClawbackLiability
Namespace Prefix: | colb_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Covered Assets And FDIC Loss Sharing Asset [Line Items] + References No definition available. + Details
Name: | colb_CoveredAssetsAndFdicLossSharingAssetLineItems
Namespace Prefix: | colb_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition FDIC Loss-sharing Asset, Impairment (Recapture) of Loans + References No definition available. + Details
Name: | colb_FDICLosssharingAssetImpairmentRecaptureofLoans
Namespace Prefix: | colb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition FDIC Loss-sharing Asset, Amortization, Net + References No definition available. + Details
Name: | colb_FdicLossSharingAssetAmortizationNet
Namespace Prefix: | colb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition FDIC Loss-sharing Asset, Cash Payments Received + References No definition available. + Details
Name: | colb_FdicLossSharingAssetCashPaymentsReceived
Namespace Prefix: | colb_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition FDIC Loss-sharing Asset, Disposals + References No definition available. + Details
Name: | colb_FdicLossSharingAssetDisposals
Namespace Prefix: | colb_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition FDIC Loss-sharing Asset, Net Reimbursable Losses + References No definition available. + Details
Name: | colb_FdicLossSharingAssetNetReimbursableLosses
Namespace Prefix: | colb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition FDIC Loss-sharing Asset, Other + References No definition available. + Details
Name: | colb_FdicLossSharingAssetOther
Namespace Prefix: | colb_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition FDIC Loss-sharing Asset, Write-downs of Other Real Estate + References No definition available. + Details
Name: | colb_FdicLossSharingAssetWriteDownsOfOtherRealEstate
Namespace Prefix: | colb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition FDIC Percentage Of Loss Recoveries + References No definition available. + Details
Name: | colb_FdicPercentageOfLossRecoveries
Namespace Prefix: | colb_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Federal deposit insurance corporation loss-sharing indemnified assets + References No definition available. + Details
Name: | colb_FederalDepositInsuranceCorporationLossSharingIndemnifiedAssets
Namespace Prefix: | colb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Federal deposit insurance corporation loss-sharing indemnified assets receivable + References No definition available. + Details
Name: | colb_FederalDepositInsuranceCorporationLossSharingIndemnifiedAssetsReceivable
Namespace Prefix: | colb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Loss Recovery Provision Effective Years + References No definition available. + Details
Name: | colb_LossRecoveryProvisionEffectiveYears
Namespace Prefix: | colb_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Loss Sharing Agreement Effective Years + References No definition available. + Details
Name: | colb_LossSharingAgreementEffectiveYears
Namespace Prefix: | colb_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Non-Single Family Covered Assets + References No definition available. + Details
Name: | colb_NonSingleFamilyCoveredAssets
Namespace Prefix: | colb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Payment Of Clawback If Losses Less Than Stated Levels, Period After Acquisition + References No definition available. + Details
Name: | colb_PaymentOfClawbackIfLossesLessThanStatedLevelsPeriodAfterAcquisition
Namespace Prefix: | colb_
Data Type: | us-types:durationStringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage Of Loss Recoveries Shared By FDIC When Loss Share Thresholds Met + References No definition available. + Details
Name: | colb_PercentageOfLossRecoveriesSharedByFdicWhenLossShareThresholdsMet
Namespace Prefix: | colb_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage of loss shared by FDIC + References No definition available. + Details
Name: | colb_PercentageOfLossSharedByFdic
Namespace Prefix: | colb_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage of loss shared by FDIC When Loss Share Thresholds Met + References No definition available. + Details
Name: | colb_PercentageOfLossSharedByFdicWhenLossShareThresholdsMet
Namespace Prefix: | colb_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Single Family Covered Assets + References No definition available. + Details
Name: | colb_SingleFamilyCoveredAssets
Namespace Prefix: | colb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Carrying amount of receivable assets originating from the indemnification agreement with the Federal Deposit Insurance Corporation (FDIC), in which the FDIC is to partially cover losses. + References No definition available. + Details
Name: | us-gaap_FDICIndemnificationAsset
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of expense related to estimated loss from loan and lease transactions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.11) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524 + Details
Name: | us-gaap_ProvisionForLoanAndLeaseLosses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | colb_FdicLossSharingAgreementsByTermAxis=colb_FdicLossSharingAssetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=colb_ColumbiaRiverBankMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=colb_AmericanMarineBankMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=colb_SummitBankMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=colb_FirstHeritageBankMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |