$COLB
COLUMBIA BANKING SYSTEM, INC. Stock $colb

$colb Overview Financials Valuation SEC Filings Company Website

2019 Q2 Form 10-Q Financial Statement

#000088734319000136 Filed on August 01, 2019

Income Statement

Concept	2019 Q2	2018 Q2	2018 Q1
Revenue	$135.4M	$120.5M	$119.1M
YoY Change	12.34%	37.32%	35.67%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development	$4.601M	$5.221M	$5.270M
YoY Change	-11.88%	10.12%	25.24%
% of Gross Profit
Depreciation & Amortization	$9.100M	$9.200M	$7.600M
YoY Change	-1.09%	16.46%	24.59%
% of Gross Profit
Operating Expenses	$4.601M	$5.221M	$5.270M
YoY Change	-11.88%	10.12%	25.24%
Operating Profit
YoY Change
Interest Expense	$10.31M	$3.875M	$3.663M
YoY Change	165.96%	138.46%	221.03%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$63.82M	$51.75M	$46.79M
YoY Change	23.32%	35.28%	17.63%
Income Tax	$12.09M	$9.999M	$6.815M
% Of Pretax Income	18.95%	19.32%	14.57%
Net Earnings	$51.72M	$41.75M	$39.97M
YoY Change	23.89%	53.87%	36.89%
Net Earnings / Revenue	38.19%	34.63%	33.55%
Basic Earnings Per Share	$0.71	$0.57	$0.55
Diluted Earnings Per Share	$0.71	$0.57	$0.55
COMMON SHARES
Basic Shares Outstanding	72.45M shares	72.39M shares	72.30M shares
Diluted Shares Outstanding	72.45M shares	72.39M shares	72.31M shares

Balance Sheet

Concept	2019 Q2	2018 Q2	2018 Q1
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$258.7M	$263.5M	$293.7M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$167.3M	$168.3M	$168.4M
YoY Change	-0.61%	14.71%	13.35%
Goodwill	$765.8M	$765.8M	$765.8M
YoY Change	0.0%	100.08%	100.08%
Intangibles	$40.54M	$51.90M	$54.99M
YoY Change	-21.88%	245.22%	237.7%
Long-Term Investments
YoY Change
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$13.09B	$12.63B	$12.53B
YoY Change	3.66%	30.39%	31.52%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$54.00M
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$50.00M	$46.00M	$24.00M
YoY Change	8.7%	-30.3%	-48.94%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$54.00M	$46.00M	$24.00M
YoY Change	17.39%	-30.3%	-48.94%
LONG-TERM LIABILITIES
Long-Term Debt	$35.00M	$36.00M	$36.00M
YoY Change	-2.78%
Other Long-Term Liabilities	$111.0M	$98.00M	$86.00M
YoY Change	13.27%	8.89%	-14.85%
Total Long-Term Liabilities	$146.0M	$134.0M	$122.0M
YoY Change	8.96%	48.89%	20.79%
TOTAL LIABILITIES
Total Short-Term Liabilities	$54.00M	$46.00M	$24.00M
Total Long-Term Liabilities	$146.0M	$134.0M	$122.0M
Total Liabilities	$10.96B	$10.66B	$10.58B
YoY Change	2.75%	27.13%	28.25%
SHAREHOLDERS EQUITY
Retained Earnings	$463.4M	$383.9M	$361.1M
YoY Change	20.72%	26.89%	25.29%
Common Stock	$1.645B	$1.637B	$1.635B
YoY Change	0.49%	63.48%	63.54%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$21.86M
YoY Change
Treasury Stock Shares	624.0K shares
Shareholders Equity	$2.134B	$1.965B	$1.948B
YoY Change
Total Liabilities & Shareholders Equity	$13.09B	$12.63B	$12.53B
YoY Change	3.66%	30.39%	31.52%

Cashflow Statement

Concept	2019 Q2	2018 Q2	2018 Q1
OPERATING ACTIVITIES
Net Income	$51.72M	$41.75M	$39.97M
YoY Change	23.89%	53.87%	36.89%
Depreciation, Depletion And Amortization	$9.100M	$9.200M	$7.600M
YoY Change	-1.09%	16.46%	24.59%
Cash From Operating Activities	$46.00M	$71.00M	$43.50M
YoY Change	-35.21%	234.91%	20.88%
INVESTING ACTIVITIES
Capital Expenditures	-$1.700M	-$2.900M	$2.099M
YoY Change	-41.38%	81.25%	524.7%
Acquisitions
YoY Change
Other Investing Activities	$80.40M	-$147.7M	$97.20M
YoY Change	-154.43%	19.02%	-243.15%
Cash From Investing Activities	$78.70M	-$150.6M	$95.08M
YoY Change	-152.26%	19.81%	-239.34%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$2.575M
YoY Change			26.29%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-78.10M	49.50M	-$187.5M
YoY Change	-257.78%	-62.98%	1946.18%
NET CHANGE
Cash From Operating Activities	46.00M	71.00M	$43.50M
Cash From Investing Activities	78.70M	-150.6M	$95.08M
Cash From Financing Activities	-78.10M	49.50M	-$187.5M
Net Change In Cash	46.60M	-30.10M	-$48.88M
YoY Change	-254.82%	-203.08%	18.01%
FREE CASH FLOW
Cash From Operating Activities	$46.00M	$71.00M	$43.50M
Capital Expenditures	-$1.700M	-$2.900M	$2.099M
Free Cash Flow	$47.70M	$73.90M	$41.40M
YoY Change	-35.45%	224.12%	16.13%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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	dei	Document Type DocumentType	10-Q
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	dei	Document Period End Date DocumentPeriodEndDate	2019-06-30
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity File Number EntityFileNumber	0-20288
	dei	Entity Registrant Name EntityRegistrantName	COLUMBIA BANKING SYSTEM, INC.
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	WA
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	91-1422237
	dei	Entity Address Address Line1 EntityAddressAddressLine1	1301 A Street
	dei	Entity Address City Or Town EntityAddressCityOrTown	Tacoma
	dei	Entity Address State Or Province EntityAddressStateOrProvince	WA
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	98402-2156
	dei	City Area Code CityAreaCode	253
	dei	Local Phone Number LocalPhoneNumber	305-1900
	dei	Security12b Title Security12bTitle	Common Stock, No Par Value
	dei	Trading Symbol TradingSymbol	COLB
	dei	Security Exchange Name SecurityExchangeName	NASDAQ
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	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	246138000	USD
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	232155000	USD
CY2019Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	218000	USD
CY2018Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	3975000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	1580000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	9827000	USD
CY2019Q2	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	124898000	USD
CY2018Q2	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	112699000	USD
	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	244558000	USD
	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	222328000	USD
CY2019Q2	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	9035000	USD
CY2018Q2	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	8683000	USD
	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	18015000	USD
	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	17423000	USD
CY2019Q2	colb	Cardrevenue Cardrevenue	3763000	USD
CY2018Q2	colb	Cardrevenue Cardrevenue	6616000	USD
	colb	Cardrevenue Cardrevenue	7425000	USD
	colb	Cardrevenue Cardrevenue	12429000	USD
CY2019Q2	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	3425000	USD
CY2018Q2	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	3219000	USD
	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	6382000	USD
	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	5949000	USD
CY2019Q2	colb	Loanrevenue Loanrevenue	3596000	USD
CY2018Q2	colb	Loanrevenue Loanrevenue	3054000	USD
	colb	Loanrevenue Loanrevenue	5985000	USD
	colb	Loanrevenue Loanrevenue	6240000	USD
CY2019Q2	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1597000	USD
CY2018Q2	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1712000	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	3116000	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	3138000	USD
	us-gaap	Noninterest Income Other NoninterestIncomeOther	4289000	USD
	us-gaap	Noninterest Income Other NoninterestIncomeOther	1667000	USD
CY2019Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	285000	USD
CY2018Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	-33000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	2132000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-11000	USD
CY2019Q2	us-gaap	Noninterest Income Other NoninterestIncomeOther	3947000	USD
CY2018Q2	us-gaap	Noninterest Income Other NoninterestIncomeOther	441000	USD
CY2019Q2	us-gaap	Noninterest Income NoninterestIncome	25648000	USD
CY2018Q2	us-gaap	Noninterest Income NoninterestIncome	23692000	USD
	us-gaap	Noninterest Income NoninterestIncome	47344000	USD
	us-gaap	Noninterest Income NoninterestIncome	46835000	USD
CY2019Q2	us-gaap	Labor And Related Expense LaborAndRelatedExpense	52015000	USD
CY2018Q2	us-gaap	Labor And Related Expense LaborAndRelatedExpense	48949000	USD
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	104100000	USD
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	99519000	USD
CY2019Q2	us-gaap	Occupancy Net OccupancyNet	8712000	USD
CY2018Q2	us-gaap	Occupancy Net OccupancyNet	9276000	USD
	us-gaap	Occupancy Net OccupancyNet	17521000	USD
	us-gaap	Occupancy Net OccupancyNet	19397000	USD
CY2019Q2	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	4601000	USD
CY2018Q2	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	5221000	USD
	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	9270000	USD
	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	10491000	USD
CY2019Q2	us-gaap	Professional Fees ProfessionalFees	6554000	USD
CY2018Q2	us-gaap	Professional Fees ProfessionalFees	4171000	USD
	us-gaap	Professional Fees ProfessionalFees	11127000	USD
	us-gaap	Professional Fees ProfessionalFees	7408000	USD
CY2019Q2	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	2649000	USD
CY2018Q2	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	3088000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	5397000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	6276000	USD
CY2019Q2	colb	Taxes Licenses And Fees TaxesLicensesAndFees	1411000	USD
CY2018Q2	colb	Taxes Licenses And Fees TaxesLicensesAndFees	1459000	USD
	colb	Taxes Licenses And Fees TaxesLicensesAndFees	3287000	USD
	colb	Taxes Licenses And Fees TaxesLicensesAndFees	2776000	USD
CY2019Q2	us-gaap	Advertising Expense AdvertisingExpense	870000	USD
CY2018Q2	us-gaap	Advertising Expense AdvertisingExpense	1622000	USD
	us-gaap	Advertising Expense AdvertisingExpense	1844000	USD
	us-gaap	Advertising Expense AdvertisingExpense	3051000	USD
CY2019Q2	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	956000	USD
CY2018Q2	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	937000	USD
CY2018Q2	colb	Netcostbenefitofoperationofotherrealestateowned Netcostbenefitofoperationofotherrealestateowned	758000	USD
	colb	Netcostbenefitofoperationofotherrealestateowned Netcostbenefitofoperationofotherrealestateowned	-592000	USD
	colb	Netcostbenefitofoperationofotherrealestateowned Netcostbenefitofoperationofotherrealestateowned	759000	USD
	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	1940000	USD
	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	1874000	USD
CY2019Q2	colb	Netcostbenefitofoperationofotherrealestateowned Netcostbenefitofoperationofotherrealestateowned	-705000	USD
CY2019Q2	us-gaap	Other Noninterest Expense OtherNoninterestExpense	9665000	USD
CY2018Q2	us-gaap	Other Noninterest Expense OtherNoninterestExpense	9162000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	17534000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	19079000	USD
CY2019Q2	us-gaap	Noninterest Expense NoninterestExpense	86728000	USD
CY2018Q2	us-gaap	Noninterest Expense NoninterestExpense	84643000	USD
	us-gaap	Noninterest Expense NoninterestExpense	171428000	USD
	us-gaap	Noninterest Expense NoninterestExpense	170630000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	63818000	USD
CY2018Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	51748000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	120474000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	98533000	USD
CY2019Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	12094000	USD
CY2018Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	9999000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	22879000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	16814000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	51724000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	41749000	USD
	us-gaap	Net Income Loss NetIncomeLoss	97595000	USD
	us-gaap	Net Income Loss NetIncomeLoss	81719000	USD
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.71
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.57
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.33
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.12
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.71
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.57
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.33
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.12
CY2019Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72451000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72385000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72486000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72343000	shares
CY2019Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	72451000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	72390000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	72487000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	72347000	shares
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	51724000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	41749000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	37029000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-7845000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	219000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	4000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	36810000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-7849000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	61000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	61000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-61000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-61000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	7233000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	0	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	7233000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	0	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	44104000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-7788000	USD
CY2019Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	95828000	USD
CY2018Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	33961000	USD
	us-gaap	Net Income Loss NetIncomeLoss	97595000	USD
	us-gaap	Net Income Loss NetIncomeLoss	81719000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	71926000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-33893000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	1636000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	82000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	70290000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-33975000	USD
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	122000	USD
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	122000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-122000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-122000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	12043000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	0	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	12043000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	0	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	82455000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-33853000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	180050000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	47866000	USD
CY2019Q1	us-gaap	Stockholders Equity StockholdersEquity	2088620000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	51724000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	44104000	USD
CY2019Q2	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	15000	USD
CY2019Q2	colb	Stock Adjustment Value Deferred Compensation StockAdjustmentValueDeferredCompensation	1000	USD
CY2019Q2	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	2243000	USD
CY2019Q2	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	314000	USD
CY2019Q2	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	30892000	USD
CY2019Q2	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	21863000	USD
CY2019Q2	us-gaap	Stockholders Equity StockholdersEquity	2133638000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	2033649000	USD
	us-gaap	Net Income Loss NetIncomeLoss	97595000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	82455000	USD
	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	893000	USD
	colb	Stock Adjustment Value Deferred Compensation StockAdjustmentValueDeferredCompensation	1000	USD
	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	4528000	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	2746000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	61656000	USD
	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	21863000	USD
CY2019Q2	us-gaap	Stockholders Equity StockholdersEquity	2133638000	USD
CY2018Q1	us-gaap	Stockholders Equity StockholdersEquity	1947923000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	41749000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-7788000	USD
CY2018Q2	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	17000	USD
CY2018Q2	colb	Stock Adjustment Deferred Compensation Shares StockAdjustmentDeferredCompensationShares	0	shares
CY2018Q2	colb	Stock Adjustment Value Deferred Compensation StockAdjustmentValueDeferredCompensation	3000	USD
CY2018Q2	colb	Stock Adjustment Value Deferred Compensation StockAdjustmentValueDeferredCompensation	3000	USD
CY2018Q2	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	2019000	USD
CY2018Q2	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	52000	USD
CY2018Q2	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	19036000	USD
CY2018Q2	us-gaap	Stockholders Equity StockholdersEquity	1964881000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	1949922000	USD
	us-gaap	Net Income Loss NetIncomeLoss	81719000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-33853000	USD
	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	736000	USD
	colb	Stock Adjustment Deferred Compensation Shares StockAdjustmentDeferredCompensationShares	0	shares
	colb	Stock Adjustment Value Deferred Compensation StockAdjustmentValueDeferredCompensation	6000	USD
	colb	Stock Adjustment Value Deferred Compensation StockAdjustmentValueDeferredCompensation	6000	USD
	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	4083000	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	2627000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	35105000	USD
CY2018Q2	us-gaap	Stockholders Equity StockholdersEquity	1964881000	USD
	us-gaap	Net Income Loss NetIncomeLoss	97595000	USD
	us-gaap	Net Income Loss NetIncomeLoss	81719000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	1580000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	9827000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	4528000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	4083000	USD
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	17298000	USD
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	16788000	USD
	us-gaap	Available For Sale Securities Gross Realized Gain Loss Net AvailableForSaleSecuritiesGrossRealizedGainLossNet	2132000	USD
	us-gaap	Available For Sale Securities Gross Realized Gain Loss Net AvailableForSaleSecuritiesGrossRealizedGainLossNet	-11000	USD
	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	666000	USD
	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	-141000	USD
	colb	Netgainlossonsaleandvaluationadjustmentsof Oreo NetgainlossonsaleandvaluationadjustmentsofOREO	507000	USD
	colb	Netgainlossonsaleandvaluationadjustmentsof Oreo NetgainlossonsaleandvaluationadjustmentsofOREO	-803000	USD
	colb	Gainonbankownedlifeinsurancedeathbenefit Gainonbankownedlifeinsurancedeathbenefit	2975000	USD
	colb	Gainonbankownedlifeinsurancedeathbenefit Gainonbankownedlifeinsurancedeathbenefit	0	USD
	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	68722000	USD
	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	67311000	USD
	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	60382000	USD
	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	66304000	USD
	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	1555000	USD
	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	2224000	USD
	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	1608000	USD
	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-36000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	16484000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-6367000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	8560000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-2017000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	98510000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	114455000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	207641000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	100485000	USD
	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	54405000	USD
	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	215612000	USD
	us-gaap	Payments To Acquire Loans Held For Investment PaymentsToAcquireLoansHeldForInvestment	49039000	USD
	us-gaap	Payments To Acquire Loans Held For Investment PaymentsToAcquireLoansHeldForInvestment	0	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	3540000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	5011000	USD
	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	117240000	USD
	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	89720000	USD
	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	259554000	USD
	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	32330000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	182125000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	219683000	USD
	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	5823000	USD
	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	5821000	USD
	us-gaap	Proceeds From Sales Of Assets Investing Activities ProceedsFromSalesOfAssetsInvestingActivities	24000	USD
	us-gaap	Proceeds From Sales Of Assets Investing Activities ProceedsFromSalesOfAssetsInvestingActivities	6236000	USD
	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	113400000	USD
	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	86200000	USD
	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	0	USD
	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	5074000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	129061000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-55484000	USD
	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-246404000	USD
	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-147891000	USD
	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	-10868000	USD
	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	-7830000	USD
	us-gaap	Proceeds From Federal Home Loan Bank Advances ProceedsFromFederalHomeLoanBankAdvances	2931000000	USD
	us-gaap	Proceeds From Federal Home Loan Bank Advances ProceedsFromFederalHomeLoanBankAdvances	2243000000	USD
	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	36000000	USD
	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	10000	USD
	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	100000	USD
	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	0	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	893000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	736000	USD
	us-gaap	Payments For Federal Home Loan Bank Advances PaymentsForFederalHomeLoanBankAdvances	2835000000	USD
	us-gaap	Payments For Federal Home Loan Bank Advances PaymentsForFederalHomeLoanBankAdvances	2155000000	USD
	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	36000000	USD
	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	10000	USD
	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	100000	USD
	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	0	USD
	colb	Repaymentsofjuniorsubordinateddebt Repaymentsofjuniorsubordinateddebt	0	USD
	colb	Repaymentsofjuniorsubordinateddebt Repaymentsofjuniorsubordinateddebt	8248000	USD
	colb	Repaymentoftermrepurchaseagreement Repaymentoftermrepurchaseagreement	0	USD
	colb	Repaymentoftermrepurchaseagreement Repaymentoftermrepurchaseagreement	25000000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	61511000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	35105000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	21863000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	2746000	USD
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	2627000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-246499000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-137965000	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-18928000	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-78994000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	277587000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	342533000	USD
CY2019Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	258659000	USD
CY2018Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	263539000	USD
	us-gaap	Interest Paid Net InterestPaidNet	16564000	USD
	us-gaap	Interest Paid Net InterestPaidNet	7573000	USD
	us-gaap	Income Taxes Paid IncomeTaxesPaid	20940000	USD
	us-gaap	Income Taxes Paid IncomeTaxesPaid	3621000	USD
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	386000	USD
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	406000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	56000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	40000	USD
	colb	Changeindividendspayableonunvestedshares Changeindividendspayableonunvestedshares	145000	USD
	colb	Changeindividendspayableonunvestedshares Changeindividendspayableonunvestedshares	0	USD
	us-gaap	Description Of New Accounting Pronouncements Not Yet Adopted DescriptionOfNewAccountingPronouncementsNotYetAdopted	<div style="line-height:120%;padding-top:12px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;font-style:italic;">Recently Issued Accounting Standards, Not Yet Adopted</span></div><div style="line-height:120%;padding-top:12px;text-indent:30px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">In April 2019, the FASB issued ASU 2019-04, </span><span style="font-family:inherit;font-size:10pt;font-style:italic;">Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments</span><span style="font-family:inherit;font-size:10pt;">. The amendments in this ASU clarify certain aspects of accounting for credit losses, hedging activities, and financial instruments (addressed by ASUs 2016-01, 2016-13, and 2017-12). Many of the amendments reflect decisions reached at FASB meetings or meetings of the Board’s credit losses transition resource group. Topics covered in this ASU include: accrued interest, transfers between classifications or categories for loans and debt securities, recoveries, reinsurance recoverables, projections of interest rate environments for variable-rate financial instruments, costs to sell when foreclosure is probable, consideration of expected prepayments when determining the effective interest rate, vintage disclosures, extension and renewal options, etc. The amendments in ASU 2019-04 are effective for fiscal years beginning after December 15, 2019 and interim periods within those fiscal years. Early adoption is permitted, including adoption in any interim period. The Company is assessing the impact that this guidance will have on its Consolidated Financial Statements.</span></div><div style="line-height:120%;padding-top:12px;text-indent:30px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">In August 2018, the FASB issued ASU 2018-15, </span><span style="font-family:inherit;font-size:10pt;font-style:italic;">Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That is a Service Contract</span><span style="font-family:inherit;font-size:10pt;">. The amendments in this ASU align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The amendments also require the entity to expense the capitalized implementation costs of a hosting arrangement that is a service contract over the term of the hosting arrangement, including reasonably certain renewal periods. The amendments in ASU 2018-15 are effective for fiscal years beginning after December 15, 2019 and interim periods within those fiscal years. Early adoption is permitted, including adoption in any interim period. The Company is assessing the impact that this guidance will have on its Consolidated Financial Statements.</span></div><div style="line-height:120%;padding-top:12px;text-indent:30px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">In June 2016, the FASB issued ASU 2016-13, </span><span style="font-family:inherit;font-size:10pt;font-style:italic;">Measurement of Credit Losses on Financial Instruments</span><span style="font-family:inherit;font-size:10pt;">. The amendments included in this ASU require an entity to reflect its current estimate of all expected credit losses for assets held at an amortized cost basis. For available for sale debt securities, credit losses will be measured in a manner similar to current GAAP, however, this ASU will require that credit losses be presented as an allowance rather than as a write-down. The amendments in ASU 2016-13 are effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, and are required to be adopted through a modified retrospective approach, with a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the ASU is effective.</span></div><div style="line-height:120%;padding-top:12px;text-indent:30px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Although the Company is in the final stages of determining an initial estimate, it currently cannot reasonably estimate the impact that the adoption of ASU 2016-13 will have on its Consolidated Financial Statements. That assessment is based upon the fact that, unlike the incurred loss models in existing GAAP, the CECL model in ASU 2016-13 does not specify a threshold for the recognition of an impairment allowance. Rather, the Company will recognize an impairment allowance equal to its estimate of lifetime expected credit losses, adjusted for prepayments, for in-scope financial instruments as of the end of the reporting period. Accordingly, the impairment allowance measured under the CECL model could increase significantly from the impairment allowance measured under the Company’s existing incurred loss model. The Company has engaged a third-party vendor to assist in the CECL calculation and has developed an internal governance framework to oversee the CECL implementation. Other significant CECL implementation matters being addressed by the Company include selecting loss estimation methodologies, identifying, sourcing and storing data, addressing data gaps, defining a reasonable and supportable forecast period, selecting historical loss information, assessing the impact to internal controls over financial reporting, and capital planning.</span></div>
CY2019Q2	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	2816003000	USD
CY2019Q2	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	60966000	USD
CY2019Q2	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	12551000	USD
CY2019Q2	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	2864418000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	3210615000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	12799000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	55966000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	3167448000	USD
CY2019Q2	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	175586000	USD
CY2018Q2	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	87000	USD
	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	3357000	USD
	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	235000	USD
CY2019Q2	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	1225000	USD
CY2018Q2	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	83000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	259554000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	32330000	USD
CY2019Q2	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	1510000	USD
CY2018Q2	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	12569000	USD
	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	1225000	USD
	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	129000	USD
CY2019Q2	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	0	USD
CY2018Q2	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-37000	USD
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	0	USD
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-117000	USD
CY2019Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	285000	USD
CY2018Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	-33000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	2132000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-11000	USD
CY2019Q2	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	95802000	USD
CY2019Q2	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	95869000	USD
CY2019Q2	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	438632000	USD
CY2019Q2	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	441541000	USD
CY2019Q2	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	1315811000	USD
CY2019Q2	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	1361873000	USD
CY2019Q2	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	965758000	USD
CY2019Q2	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	965135000	USD
CY2019Q2	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	2816003000	USD
CY2019Q2	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	2864418000	USD
CY2019Q2	us-gaap	Debt Securities Available For Sale Restricted DebtSecuritiesAvailableForSaleRestricted	489515000	USD
CY2019Q2	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	10562000	USD
CY2019Q2	colb	Availableforsale Securities Continuous Unrealized Loss Position Lessthan12 Months Aggregate Loss Instant AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessthan12MonthsAggregateLossInstant	39000	USD
CY2019Q2	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	955713000	USD
CY2019Q2	colb	Availableforsale Securities Continuous Unrealized Loss Position12 Monthsor Longer Aggregate Lossinstant AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLossinstant	12512000	USD
CY2019Q2	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	966275000	USD
CY2019Q2	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	12551000	USD
CY2018Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	276306000	USD
CY2018Q4	colb	Availableforsale Securities Continuous Unrealized Loss Position Lessthan12 Months Aggregate Loss Instant AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessthan12MonthsAggregateLossInstant	1598000	USD
CY2018Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	1873565000	USD
CY2018Q4	colb	Availableforsale Securities Continuous Unrealized Loss Position12 Monthsor Longer Aggregate Lossinstant AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLossinstant	54368000	USD
CY2018Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	2149871000	USD
CY2018Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	55966000	USD
CY2019Q2	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	37415000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	42194000	USD
CY2019Q2	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	8646990000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	8391511000	USD
CY2019Q2	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	80517000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	83369000	USD
CY2019Q2	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	8566473000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	8308142000	USD
CY2019Q2	us-gaap	Loans Receivable Held For Sale Net Not Part Of Disposal Group LoansReceivableHeldForSaleNetNotPartOfDisposalGroup	12189000	USD
CY2018Q4	us-gaap	Loans Receivable Held For Sale Net Not Part Of Disposal Group LoansReceivableHeldForSaleNetNotPartOfDisposalGroup	3849000	USD
CY2019Q2	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	39038000	USD
CY2019Q2	colb	Financing Receivable Unpaid Principal Balance Nonaccrual Status FinancingReceivableUnpaidPrincipalBalanceNonaccrualStatus	48440000	USD
CY2018Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	54842000	USD
CY2018Q4	colb	Financing Receivable Unpaid Principal Balance Nonaccrual Status FinancingReceivableUnpaidPrincipalBalanceNonaccrualStatus	65358000	USD
CY2019Q2	colb	Financing Receivable Modifications Additional Commitment To Lend FinancingReceivableModificationsAdditionalCommitmentToLend	464000	USD
CY2018Q4	colb	Financing Receivable Modifications Additional Commitment To Lend FinancingReceivableModificationsAdditionalCommitmentToLend	2100000	USD
	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	1
	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	26000	USD
CY2019Q1	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	21849000	USD
CY2018Q1	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	29355000	USD
CY2018Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	21949000	USD
CY2017Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	31176000	USD
CY2019Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	1999000	USD
CY2018Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	1937000	USD
	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	3576000	USD
	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	4202000	USD
CY2019Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Disposals Of Loans CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldDisposalsOfLoans	-3000	USD
CY2018Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Disposals Of Loans CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldDisposalsOfLoans	7000	USD
	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Disposals Of Loans CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldDisposalsOfLoans	-106000	USD
	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Disposals Of Loans CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldDisposalsOfLoans	166000	USD
CY2019Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	1136000	USD
CY2018Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	-2061000	USD
	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	2510000	USD
	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	-1458000	USD
CY2019Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	20989000	USD
CY2018Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	25350000	USD
CY2019Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	20989000	USD
CY2018Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	25350000	USD
CY2019Q1	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	83274000	USD
CY2019Q2	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	5287000	USD
CY2019Q2	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	2312000	USD
CY2019Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	218000	USD
CY2019Q2	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	80517000	USD
CY2019Q2	colb	Loan And Lease Losses Specific Reserve LoanAndLeaseLossesSpecificReserve	1475000	USD
CY2019Q2	colb	Loan And Lease Losses General Allocation LoanAndLeaseLossesGeneralAllocation	79042000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	83369000	USD
	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	8275000	USD
	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	3843000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	1580000	USD
CY2019Q2	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	80517000	USD
CY2019Q2	colb	Loan And Lease Losses Specific Reserve LoanAndLeaseLossesSpecificReserve	1475000	USD
CY2019Q2	colb	Loan And Lease Losses General Allocation LoanAndLeaseLossesGeneralAllocation	79042000	USD
CY2018Q1	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	79827000	USD
CY2018Q2	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	7242000	USD
CY2018Q2	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	3590000	USD
CY2018Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	3975000	USD
CY2018Q2	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	80150000	USD
CY2018Q2	colb	Loan And Lease Losses Specific Reserve LoanAndLeaseLossesSpecificReserve	256000	USD
	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	6226000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	9827000	USD
CY2018Q2	colb	Loan And Lease Losses General Allocation LoanAndLeaseLossesGeneralAllocation	79894000	USD
CY2017Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	75646000	USD
	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	11549000	USD
CY2018Q2	colb	Loan And Lease Losses General Allocation LoanAndLeaseLossesGeneralAllocation	79894000	USD
CY2018Q2	colb	Transfer Other Real Estate Write Down TransferOtherRealEstateWriteDown	110000	USD
CY2018Q2	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	80150000	USD
CY2018Q2	colb	Loan And Lease Losses Specific Reserve LoanAndLeaseLossesSpecificReserve	256000	USD
CY2019Q1	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	3780000	USD
CY2018Q1	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	4330000	USD
CY2018Q4	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	4330000	USD
CY2017Q4	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	3130000	USD
CY2019Q2	colb	Allowance For Loan And Lease Losses Net Changes In Unfunded Commitments And Letters Of Credit Allowance AllowanceForLoanAndLeaseLossesNetChangesInUnfundedCommitmentsAndLettersOfCreditAllowance	200000	USD
CY2018Q2	colb	Allowance For Loan And Lease Losses Net Changes In Unfunded Commitments And Letters Of Credit Allowance AllowanceForLoanAndLeaseLossesNetChangesInUnfundedCommitmentsAndLettersOfCreditAllowance	-650000	USD
	colb	Allowance For Loan And Lease Losses Net Changes In Unfunded Commitments And Letters Of Credit Allowance AllowanceForLoanAndLeaseLossesNetChangesInUnfundedCommitmentsAndLettersOfCreditAllowance	-350000	USD
	colb	Allowance For Loan And Lease Losses Net Changes In Unfunded Commitments And Letters Of Credit Allowance AllowanceForLoanAndLeaseLossesNetChangesInUnfundedCommitmentsAndLettersOfCreditAllowance	550000	USD
CY2019Q2	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	3980000	USD
CY2018Q2	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	3680000	USD
CY2019Q2	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	3980000	USD
CY2018Q2	colb	Allowance For Unfunded Loan Commitments And Letters Of Credit AllowanceForUnfundedLoanCommitmentsAndLettersOfCredit	3680000	USD
CY2019Q1	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	6075000	USD
CY2018Q1	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	11507000	USD
CY2018Q4	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	6019000	USD
CY2017Q4	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	13298000	USD
CY2019Q2	colb	Real Estate Acquired Through Foreclosure Transfers In Net Of Write Downs RealEstateAcquiredThroughForeclosureTransfersInNetOfWriteDowns	0	USD
CY2018Q2	colb	Real Estate Acquired Through Foreclosure Transfers In Net Of Write Downs RealEstateAcquiredThroughForeclosureTransfersInNetOfWriteDowns	0	USD
	colb	Real Estate Acquired Through Foreclosure Transfers In Net Of Write Downs RealEstateAcquiredThroughForeclosureTransfersInNetOfWriteDowns	386000	USD
	colb	Transfer Other Real Estate Write Down TransferOtherRealEstateWriteDown	195000	USD
	colb	Transfer Other Real Estate Write Down TransferOtherRealEstateWriteDown	202000	USD
	colb	Real Estate Acquired Through Foreclosure Transfers In Net Of Write Downs RealEstateAcquiredThroughForeclosureTransfersInNetOfWriteDowns	406000	USD
CY2019Q2	colb	Transfer Other Real Estate Write Down TransferOtherRealEstateWriteDown	0	USD
CY2018Q2	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	919000	USD
CY2019Q2	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	40540000	USD
CY2018Q2	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	51897000	USD
CY2019Q2	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	40540000	USD
CY2018Q2	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	51897000	USD
CY2019Q2	colb	Goodwill And Intangible Assets Total GoodwillAndIntangibleAssetsTotal	806382000	USD
CY2019Q2	us-gaap	Proceeds From Sale Of Wholly Owned Real Estate And Real Estate Acquired In Settlement Of Loans ProceedsFromSaleOfWhollyOwnedRealEstateAndRealEstateAcquiredInSettlementOfLoans	5673000	USD
CY2018Q2	us-gaap	Proceeds From Sale Of Wholly Owned Real Estate And Real Estate Acquired In Settlement Of Loans ProceedsFromSaleOfWhollyOwnedRealEstateAndRealEstateAcquiredInSettlementOfLoans	3759000	USD
	us-gaap	Proceeds From Sale Of Wholly Owned Real Estate And Real Estate Acquired In Settlement Of Loans ProceedsFromSaleOfWhollyOwnedRealEstateAndRealEstateAcquiredInSettlementOfLoans	5794000	USD
	us-gaap	Proceeds From Sale Of Wholly Owned Real Estate And Real Estate Acquired In Settlement Of Loans ProceedsFromSaleOfWhollyOwnedRealEstateAndRealEstateAcquiredInSettlementOfLoans	5821000	USD
CY2019Q2	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	716000	USD
CY2018Q2	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	-558000	USD
	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	702000	USD
	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	-601000	USD
CY2019Q2	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	1118000	USD
CY2018Q2	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	7080000	USD
CY2019Q2	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	1118000	USD
CY2018Q2	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	7080000	USD
CY2019Q2	us-gaap	Mortgage Loans In Process Of Foreclosure Amount MortgageLoansInProcessOfForeclosureAmount	586000	USD
CY2019Q2	us-gaap	Goodwill Goodwill	765842000	USD
CY2018Q2	us-gaap	Goodwill Goodwill	765842000	USD
CY2019Q2	us-gaap	Goodwill Goodwill	765842000	USD
CY2018Q2	us-gaap	Goodwill Goodwill	765842000	USD
CY2019Q2	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	919000	USD
CY2018Q2	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	919000	USD
CY2019Q2	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	919000	USD
CY2018Q2	colb	Goodwill And Intangible Assets Total GoodwillAndIntangibleAssetsTotal	817739000	USD
CY2019Q2	colb	Goodwill And Intangible Assets Total GoodwillAndIntangibleAssetsTotal	806382000	USD
CY2018Q2	colb	Goodwill And Intangible Assets Total GoodwillAndIntangibleAssetsTotal	817739000	USD
CY2019Q2	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	5082000	USD
CY2019Q2	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	8724000	USD
CY2019Q2	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	7264000	USD
CY2019Q2	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	5880000	USD
CY2019Q2	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	4552000	USD
CY2019Q2	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	47875000	USD
CY2019Q2	us-gaap	Operating Lease Liability OperatingLeaseLiability	53875000	USD
CY2019Q2	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y8M12D
CY2019Q2	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.032
CY2019Q2	us-gaap	Operating Lease Payments OperatingLeasePayments	5600000	USD
CY2019Q2	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	3600000	USD
CY2019Q2	us-gaap	Operating Lease Cost OperatingLeaseCost	2765000	USD
	us-gaap	Operating Lease Cost OperatingLeaseCost	5585000	USD
CY2019Q2	us-gaap	Variable Lease Cost VariableLeaseCost	517000	USD
	us-gaap	Variable Lease Cost VariableLeaseCost	1023000	USD
CY2019Q2	us-gaap	Sublease Income SubleaseIncome	306000	USD
	us-gaap	Sublease Income SubleaseIncome	621000	USD
CY2019Q2	us-gaap	Lease Cost LeaseCost	2976000	USD
	us-gaap	Lease Cost LeaseCost	5987000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	6796000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Remainder Of Fiscal Year LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear	5494000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	10244000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	9223000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	8611000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	7332000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	20448000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	61352000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	7477000	USD
CY2019Q2	us-gaap	Operating Lease Liability OperatingLeaseLiability	53875000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	10947000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	9766000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	8729000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	8102000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	18703000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	63043000	USD
CY2019Q2	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	30000000.0	USD
CY2019Q2	us-gaap	Interest Rate Cash Flow Hedge Gain Loss To Be Reclassified During Next12 Months Net InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet	2100000	USD
	us-gaap	Gain Loss On Derivative Instruments Net Pretax GainLossOnDerivativeInstrumentsNetPretax	-2000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	0	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	0	USD
CY2019Q2	us-gaap	Unrealized Gain Loss On Interest Rate Cash Flow Hedges Pretax Accumulated Other Comprehensive Income Loss UnrealizedGainLossOnInterestRateCashFlowHedgesPretaxAccumulatedOtherComprehensiveIncomeLoss	9423000	USD
CY2018Q2	us-gaap	Unrealized Gain Loss On Interest Rate Cash Flow Hedges Pretax Accumulated Other Comprehensive Income Loss UnrealizedGainLossOnInterestRateCashFlowHedgesPretaxAccumulatedOtherComprehensiveIncomeLoss	0	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	0	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	0	USD
	us-gaap	Unrealized Gain Loss On Interest Rate Cash Flow Hedges Pretax Accumulated Other Comprehensive Income Loss UnrealizedGainLossOnInterestRateCashFlowHedgesPretaxAccumulatedOtherComprehensiveIncomeLoss	15691000	USD
	us-gaap	Unrealized Gain Loss On Interest Rate Cash Flow Hedges Pretax Accumulated Other Comprehensive Income Loss UnrealizedGainLossOnInterestRateCashFlowHedgesPretaxAccumulatedOtherComprehensiveIncomeLoss	0	USD
	us-gaap	Gain Loss On Interest Rate Cash Flow Hedge Ineffectiveness GainLossOnInterestRateCashFlowHedgeIneffectiveness	0	USD
CY2019Q2	colb	Repurchaseagreementsamountsoffsetinbalancesheet Repurchaseagreementsamountsoffsetinbalancesheet	0	USD
CY2019Q2	colb	Repurchaseagreementsnetamountpresentedinstatementoffinancialposition Repurchaseagreementsnetamountpresentedinstatementoffinancialposition	50226000	USD
CY2019Q2	us-gaap	Securities Sold Under Agreements To Repurchase Collateral Right To Reclaim Securities SecuritiesSoldUnderAgreementsToRepurchaseCollateralRightToReclaimSecurities	50226000	USD
CY2019Q2	colb	Securitiessoldunderagreementstorepurchaseamountnotoffset Securitiessoldunderagreementstorepurchaseamountnotoffset	0	USD
CY2018Q4	colb	Repurchaseagreementsamountsoffsetinbalancesheet Repurchaseagreementsamountsoffsetinbalancesheet	0	USD
CY2018Q4	colb	Repurchaseagreementsnetamountpresentedinstatementoffinancialposition Repurchaseagreementsnetamountpresentedinstatementoffinancialposition	61094000	USD
CY2018Q4	us-gaap	Securities Sold Under Agreements To Repurchase Collateral Right To Reclaim Securities SecuritiesSoldUnderAgreementsToRepurchaseCollateralRightToReclaimSecurities	61094000	USD
CY2018Q4	colb	Securitiessoldunderagreementstorepurchaseamountnotoffset Securitiessoldunderagreementstorepurchaseamountnotoffset	0	USD
CY2019Q2	us-gaap	Secured Borrowings Gross Including Not Subject To Master Netting Arrangement SecuredBorrowingsGrossIncludingNotSubjectToMasterNettingArrangement	50226000	USD
CY2019Q2	us-gaap	Secured Borrowings Gross Difference Amount SecuredBorrowingsGrossDifferenceAmount	0	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	82455000	USD
CY2019Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.28
CY2019Q1	colb	Common Stock Special Cash Dividends Per Share Declared CommonStockSpecialCashDividendsPerShareDeclared	0.14
CY2019Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.28
CY2019Q2	colb	Common Stock Special Cash Dividends Per Share Declared CommonStockSpecialCashDividendsPerShareDeclared	0.14
CY2019Q2	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	624158	shares
CY2019Q2	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	35.03
CY2019Q2	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	2275842	shares
CY2019Q1	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	3046000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	44262000	USD
CY2019Q2	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	158000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	44104000	USD
CY2019Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	47150000	USD
CY2018Q1	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-48133000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-7845000	USD
CY2018Q2	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-57000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-7788000	USD
CY2018Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-55921000	USD
CY2018Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-35305000	USD
	us-gaap	Net Income Loss NetIncomeLoss	81719000	USD
CY2019Q2	colb	Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares	378000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	83969000	USD
	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	1514000	USD
CY2017Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-22225000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-33893000	USD
	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-40000	USD
CY2018Q2	colb	Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares	473000	USD
	colb	Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares	838000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-33853000	USD
	colb	Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares Earningsallocatedtoparticipatingsecuritiesnonvestedrestrictedshares	909000	USD
CY2019Q2	colb	Basic Earnings Allocated To Common Shareholders BasicEarningsAllocatedToCommonShareholders	51346000	USD
CY2019Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	47150000	USD
CY2018Q2	colb	Basic Earnings Allocated To Common Shareholders BasicEarningsAllocatedToCommonShareholders	41276000	USD
	colb	Basic Earnings Allocated To Common Shareholders BasicEarningsAllocatedToCommonShareholders	96757000	USD
	us-gaap	Net Income Loss NetIncomeLoss	97595000	USD
CY2018Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-55921000	USD
CY2019Q2	us-gaap	Fair Value Liabilities Level1 To Level2 Transfers Amount FairValueLiabilitiesLevel1ToLevel2TransfersAmount	0	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	51724000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	41749000	USD
	colb	Basic Earnings Allocated To Common Shareholders BasicEarningsAllocatedToCommonShareholders	80810000	USD
CY2019Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72451000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72385000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72486000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72343000	shares
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.71
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.57
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.33
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.12
CY2019Q2	colb	Diluted Earnings Allocated To Common Shareholders DilutedEarningsAllocatedToCommonShareholders	51346000	USD
CY2018Q2	colb	Diluted Earnings Allocated To Common Shareholders DilutedEarningsAllocatedToCommonShareholders	41276000	USD
	colb	Diluted Earnings Allocated To Common Shareholders DilutedEarningsAllocatedToCommonShareholders	96757000	USD
	colb	Diluted Earnings Allocated To Common Shareholders DilutedEarningsAllocatedToCommonShareholders	80810000	USD
CY2019Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72451000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72385000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72486000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	72343000	shares
CY2019Q2	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	0	shares
CY2018Q2	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	5000	shares
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	1000	shares
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.71
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.57
CY2019Q2	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2018Q2	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	3000	shares
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	4000	shares
CY2019Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	72451000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	72390000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	72487000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	72347000	shares
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.33
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.12
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	7000	shares
CY2019Q2	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	9035000	USD
CY2018Q2	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	8683000	USD
	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	18015000	USD
	colb	Depositaccountandtreasurymanagementfees Depositaccountandtreasurymanagementfees	17423000	USD
CY2019Q2	colb	Cardrevenue Cardrevenue	3763000	USD
CY2018Q2	colb	Cardrevenue Cardrevenue	6616000	USD
	colb	Cardrevenue Cardrevenue	7425000	USD
	colb	Cardrevenue Cardrevenue	12429000	USD
CY2019Q2	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	3425000	USD
CY2018Q2	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	3219000	USD
	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	6382000	USD
	colb	Financialservicesandtrustrevenue Financialservicesandtrustrevenue	5949000	USD
CY2019Q2	colb	Revenuefromcontractswithcustomers Revenuefromcontractswithcustomers	16223000	USD
CY2018Q2	colb	Revenuefromcontractswithcustomers Revenuefromcontractswithcustomers	18518000	USD
	colb	Revenuefromcontractswithcustomers Revenuefromcontractswithcustomers	31822000	USD
	colb	Revenuefromcontractswithcustomers Revenuefromcontractswithcustomers	35801000	USD
CY2019Q2	colb	Noninterestincomeexcludingrevenuefromcontractswithcustomers Noninterestincomeexcludingrevenuefromcontractswithcustomers	9425000	USD
CY2018Q2	colb	Noninterestincomeexcludingrevenuefromcontractswithcustomers Noninterestincomeexcludingrevenuefromcontractswithcustomers	5174000	USD
	colb	Noninterestincomeexcludingrevenuefromcontractswithcustomers Noninterestincomeexcludingrevenuefromcontractswithcustomers	15522000	USD
	colb	Noninterestincomeexcludingrevenuefromcontractswithcustomers Noninterestincomeexcludingrevenuefromcontractswithcustomers	11034000	USD
CY2019Q2	us-gaap	Noninterest Income NoninterestIncome	25648000	USD
CY2018Q2	us-gaap	Noninterest Income NoninterestIncome	23692000	USD
	us-gaap	Noninterest Income NoninterestIncome	47344000	USD
	us-gaap	Noninterest Income NoninterestIncome	46835000	USD

Files In Submission

Name	View Source	Status
0000887343-19-000136-index-headers.html	Edgar Link	pending
0000887343-19-000136-index.html	Edgar Link	pending
0000887343-19-000136.txt	Edgar Link	pending
0000887343-19-000136-xbrl.zip	Edgar Link	pending
colb-20190630.xsd	Edgar Link	pending
colb-20190630_cal.xml	Edgar Link	unprocessable
colb-20190630_def.xml	Edgar Link	unprocessable
colb-20190630_lab.xml	Edgar Link	unprocessable
colb-20190630_pre.xml	Edgar Link	unprocessable
colb2q2019ex101changei.htm	Edgar Link	pending
colb2q2019ex102seconda.htm	Edgar Link	pending
colb2q2019ex103seconda.htm	Edgar Link	pending
colb2q2019ex104thirdam.htm	Edgar Link	pending
colb2q2019ex311.htm	Edgar Link	pending
colb2q2019ex312.htm	Edgar Link	pending
colb2q2019ex32.htm	Edgar Link	pending
colb2q2019form10-q.htm	Edgar Link	pending
colb2q2019form10-q_htm.xml	Edgar Link	completed
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
R1.htm	Edgar Link	pending
R10.htm	Edgar Link	pending
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R75.htm	Edgar Link	pending
R8.htm	Edgar Link	pending
R9.htm	Edgar Link	pending
report.css	Edgar Link	pending
Show.js	Edgar Link	pending

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$COLB
COLUMBIA BANKING SYSTEM, INC. Stock $colb

2019 Q2 Form 10-Q Financial Statement

#000088734319000136 Filed on August 01, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$COLB COLUMBIA BANKING SYSTEM, INC. Stock $colb

2019 Q2 Form 10-Q Financial Statement

#000088734319000136 Filed on August 01, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$COLB
COLUMBIA BANKING SYSTEM, INC. Stock $colb