$CATY
CATHAY GENERAL BANCORP Stock $caty

$caty Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-K Financial Statement

#000143774921004299 Filed on March 01, 2021

Income Statement

Concept	2020 Q4	2019 Q4	2019 Q3
Revenue			$197.8M
YoY Change			11.85%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$2.100M	$1.800M	$1.700M
YoY Change	16.67%	5.88%	0.0%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense	$27.78M	$50.02M	$50.83M
YoY Change	-44.46%	30.15%	59.94%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$81.23M	$83.67M	$93.81M
YoY Change	-2.92%	2.23%	6.05%
Income Tax	$10.33M	$16.29M	$20.97M
% Of Pretax Income	12.72%	19.47%	22.36%
Net Earnings	$70.89M	$67.38M	$72.84M
YoY Change	5.22%	4.22%	4.41%
Net Earnings / Revenue			36.82%
Basic Earnings Per Share	$0.89	$0.85	$0.91
Diluted Earnings Per Share	$0.89	$0.84	$0.91
COMMON SHARES
Basic Shares Outstanding	79.66M	79.71M	79.74M
Diluted Shares Outstanding			79.99M

Balance Sheet

Concept	2020 Q4	2019 Q4	2019 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$1.421B	$593.8M	$825.1M
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	$103.0M	$104.2M	$103.8M
YoY Change	-1.19%	1.02%	1.22%
Goodwill	$372.2M	$372.2M	$372.2M
YoY Change	0.0%	0.0%	0.0%
Intangibles	$5.434M	$6.296M	$6.821M
YoY Change	-13.69%	-12.48%	-7.71%
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	$19.04B	$18.09B	$18.00B
YoY Change	5.24%	7.8%	9.37%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$33.00M	$36.00M	$36.00M
YoY Change	-8.33%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$25.68M
YoY Change	-100.0%
Long-Term Debt Due	$0.00	$0.00	$26.00M
YoY Change		-100.0%	36.84%
Total Short-Term Liabilities	$33.00M	$36.00M	$62.00M
YoY Change	-8.33%	89.47%	226.32%
LONG-TERM LIABILITIES
Long-Term Debt	$143.0M	$148.0M	$165.0M
YoY Change	-3.38%	-21.28%	-14.51%
Other Long-Term Liabilities	$176.0M	$217.0M	$261.0M
YoY Change	-18.89%	7.96%	14.98%
Total Long-Term Liabilities	$319.0M	$365.0M	$426.0M
YoY Change	-12.6%	-6.17%	1.43%
TOTAL LIABILITIES
Total Short-Term Liabilities	$33.00M	$36.00M	$62.00M
Total Long-Term Liabilities	$319.0M	$365.0M	$426.0M
Total Liabilities	$16.62B	$15.80B	$15.76B
YoY Change	5.22%	7.75%	9.86%
SHAREHOLDERS EQUITY
Retained Earnings	$1.789B	$1.659B	$1.616B
YoY Change	7.85%	12.17%	12.3%
Common Stock	$906.0K	$900.0K	$900.0K
YoY Change	0.67%	0.22%	0.45%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$342.1M	$318.5M	$318.5M
YoY Change	7.41%	12.86%	32.95%
Treasury Stock Shares	$11.13M	$10.33M	$10.33M
Shareholders Equity	$2.418B	$2.294B	$2.246B
YoY Change
Total Liabilities & Shareholders Equity	$19.04B	$18.09B	$18.00B
YoY Change	5.24%	7.8%	9.37%

Cashflow Statement

Concept	2020 Q4	2019 Q4	2019 Q3
OPERATING ACTIVITIES
Net Income	$70.89M	$67.38M	$72.84M
YoY Change	5.22%	4.22%	4.41%
Depreciation, Depletion And Amortization	$2.100M	$1.800M	$1.700M
YoY Change	16.67%	5.88%	0.0%
Cash From Operating Activities	$86.90M	$111.3M	$150.2M
YoY Change	-21.92%	14.51%	68.39%
INVESTING ACTIVITIES
Capital Expenditures	-$1.400M	-$2.000M	-$2.400M
YoY Change	-30.0%	-9.09%	33.33%
Acquisitions
YoY Change
Other Investing Activities	-$65.50M	-$380.0M	-$183.2M
YoY Change	-82.76%	16.56%	46.79%
Cash From Investing Activities	-$66.90M	-$382.0M	-$185.7M
YoY Change	-82.49%	16.39%	46.91%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-32.90M	39.40M	302.9M
YoY Change	-183.5%	-84.51%	40.75%
NET CHANGE
Cash From Operating Activities	86.90M	111.3M	150.2M
Cash From Investing Activities	-66.90M	-382.0M	-185.7M
Cash From Financing Activities	-32.90M	39.40M	302.9M
Net Change In Cash	-12.90M	-231.3M	267.4M
YoY Change	-94.42%	-1092.7%	50.22%
FREE CASH FLOW
Cash From Operating Activities	$86.90M	$111.3M	$150.2M
Capital Expenditures	-$1.400M	-$2.000M	-$2.400M
Free Cash Flow	$88.30M	$113.3M	$152.6M
YoY Change	-22.07%	13.98%	67.69%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2020Q4	caty	Variable Interest Entity Primary Beneficiary Number Of Entities VariableInterestEntityPrimaryBeneficiaryNumberOfEntities	10	pure
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CY2018	us-gaap	Noninterest Income NoninterestIncome	31707000	USD
CY2020	us-gaap	Salaries Wages And Officers Compensation SalariesWagesAndOfficersCompensation	124022000	USD
CY2019	us-gaap	Salaries Wages And Officers Compensation SalariesWagesAndOfficersCompensation	129300000	USD
CY2018	us-gaap	Salaries Wages And Officers Compensation SalariesWagesAndOfficersCompensation	124477000	USD
CY2020	us-gaap	Occupancy Net OccupancyNet	20634000	USD
CY2019	us-gaap	Occupancy Net OccupancyNet	22004000	USD
CY2018	us-gaap	Occupancy Net OccupancyNet	20690000	USD
CY2020	us-gaap	Equipment Expense EquipmentExpense	11133000	USD
CY2019	us-gaap	Equipment Expense EquipmentExpense	11113000	USD
CY2018	us-gaap	Equipment Expense EquipmentExpense	11402000	USD
CY2020	us-gaap	Professional Fees ProfessionalFees	21856000	USD
CY2019	us-gaap	Professional Fees ProfessionalFees	23107000	USD
CY2018	us-gaap	Professional Fees ProfessionalFees	22810000	USD
CY2020	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	14897000	USD
CY2019	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	13210000	USD
CY2018	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	12438000	USD
CY2020	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	8999000	USD
CY2019	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	9617000	USD
CY2018	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	8000000	USD
CY2020	us-gaap	Marketing Expense MarketingExpense	5224000	USD
CY2019	us-gaap	Marketing Expense MarketingExpense	7585000	USD
CY2018	us-gaap	Marketing Expense MarketingExpense	7837000	USD
CY2020	caty	Foreclosed Real Estate Expense Income ForeclosedRealEstateExpenseIncome	-3091000	USD
CY2019	caty	Foreclosed Real Estate Expense Income ForeclosedRealEstateExpenseIncome	1115000	USD
CY2018	caty	Foreclosed Real Estate Expense Income ForeclosedRealEstateExpenseIncome	-719000	USD
CY2020	caty	Operations Of Affordable Housing Investments Net And Alternative Energy Partnerships Net OperationsOfAffordableHousingInvestmentsNetAndAlternativeEnergyPartnershipsNet	58225000	USD
CY2019	caty	Operations Of Affordable Housing Investments Net And Alternative Energy Partnerships Net OperationsOfAffordableHousingInvestmentsNetAndAlternativeEnergyPartnershipsNet	39731000	USD
CY2018	caty	Operations Of Affordable Housing Investments Net And Alternative Energy Partnerships Net OperationsOfAffordableHousingInvestmentsNetAndAlternativeEnergyPartnershipsNet	40515000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	687000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	687000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	876000	USD
CY2020	caty	Business Combination Acquisition And Integration Costs BusinessCombinationAcquisitionAndIntegrationCosts	0	USD
CY2019	caty	Business Combination Acquisition And Integration Costs BusinessCombinationAcquisitionAndIntegrationCosts	0	USD
CY2018	caty	Business Combination Acquisition And Integration Costs BusinessCombinationAcquisitionAndIntegrationCosts	2105000	USD
CY2020	caty	Debt Redemption Cost DebtRedemptionCost	693000	USD
CY2019	caty	Debt Redemption Cost DebtRedemptionCost	0	USD
CY2018	caty	Debt Redemption Cost DebtRedemptionCost	0	USD
CY2020	us-gaap	Other Noninterest Expense OtherNoninterestExpense	20186000	USD
CY2019	us-gaap	Other Noninterest Expense OtherNoninterestExpense	19819000	USD
CY2018	us-gaap	Other Noninterest Expense OtherNoninterestExpense	13988000	USD
CY2020	us-gaap	Noninterest Expense NoninterestExpense	283465000	USD
CY2019	us-gaap	Noninterest Expense NoninterestExpense	277288000	USD
CY2018	us-gaap	Noninterest Expense NoninterestExpense	264419000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	253965000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	349369000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	337687000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	25105000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	70234000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	65802000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	228860000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	279135000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	271885000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	7680000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	23628000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-7934000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-3478000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-3171000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	1525000	USD
CY2020	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	1194000	USD
CY2019	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	149000	USD
CY2018	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	15000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	3008000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	20308000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-6424000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	231868000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	299443000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	265461000	USD
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.88
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.49
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.35
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.87
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.48
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.33
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	79584560
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	79999703
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	81131269
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	79777847
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	80247893
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	81607346
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	1973304000	USD
CY2018	caty	Cumulative Effect Of Changes In Accounting Principlesequity Securities CumulativeEffectOfChangesInAccountingPrinciplesequitySecurities	0	USD
CY2018	caty	Reclassification Of Tax Effects In Accumulated Other Comprehensive Income Resulting From The New Corporate Income Tax Rate ReclassificationOfTaxEffectsInAccumulatedOtherComprehensiveIncomeResultingFromTheNewCorporateIncomeTaxRate	0	USD
CY2018	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	2822000	USD
CY2018	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	1000	USD
CY2018	caty	Stock Issued During Period Value Warrants Exercised StockIssuedDuringPeriodValueWarrantsExercised	0	USD
CY2018	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	2440000	USD
CY2018	us-gaap	Stock Issued During Period Value Issued For Services StockIssuedDuringPeriodValueIssuedForServices	649000	USD
CY2018	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	838000	USD
CY2018	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	42648000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	7325000	USD
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	83446000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-6424000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	271885000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	2121866000	USD
CY2019	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	3366000	USD
CY2019	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	1000	USD
CY2019	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	2311000	USD
CY2019	us-gaap	Stock Issued During Period Value Issued For Services StockIssuedDuringPeriodValueIssuedForServices	749000	USD
CY2019	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	36301000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	6601000	USD
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	99131000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	20308000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	279135000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	2294283000	USD
CY2020	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	9777000	USD
CY2020	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	2000	USD
CY2020	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	1911000	USD
CY2020	us-gaap	Stock Issued During Period Value Issued For Services StockIssuedDuringPeriodValueIssuedForServices	800000	USD
CY2020	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	23593000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	5606000	USD
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	98688000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	3008000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	228860000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	2418144000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	228860000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	279135000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	271885000	USD
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	57500000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-7000000	USD
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-4500000	USD
CY2020	caty	Provision Reversal For Losses On Other Real Estate Owned ProvisionReversalForLossesOnOtherRealEstateOwned	717000	USD
CY2019	caty	Provision Reversal For Losses On Other Real Estate Owned ProvisionReversalForLossesOnOtherRealEstateOwned	681000	USD
CY2018	caty	Provision Reversal For Losses On Other Real Estate Owned ProvisionReversalForLossesOnOtherRealEstateOwned	0	USD
CY2020	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	9486000	USD
CY2019	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-9825000	USD
CY2018	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-2343000	USD
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	7660000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	6756000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	7314000	USD
CY2020	caty	Amortization Of Right Of Use Asset Operating Lease AmortizationOfRightOfUseAssetOperatingLease	8852000	USD
CY2019	caty	Amortization Of Right Of Use Asset Operating Lease AmortizationOfRightOfUseAssetOperatingLease	8366000	USD
CY2018	caty	Amortization Of Right Of Use Asset Operating Lease AmortizationOfRightOfUseAssetOperatingLease	0	USD
CY2020	caty	Change In Operating Lease Liabilities ChangeInOperatingLeaseLiabilities	-2389000	USD
CY2019	caty	Change In Operating Lease Liabilities ChangeInOperatingLeaseLiabilities	-7157000	USD
CY2018	caty	Change In Operating Lease Liabilities ChangeInOperatingLeaseLiabilities	0	USD
CY2020	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	4216000	USD
CY2019	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	212000	USD
CY2018	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	1187000	USD
CY2020	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	413000	USD
CY2019	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	804000	USD
CY2018	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	-0	USD
CY2020	caty	Proceeds From Sale Of Loans Operating Activities ProceedsFromSaleOfLoansOperatingActivities	11098000	USD
CY2019	caty	Proceeds From Sale Of Loans Operating Activities ProceedsFromSaleOfLoansOperatingActivities	75257000	USD
CY2018	caty	Proceeds From Sale Of Loans Operating Activities ProceedsFromSaleOfLoansOperatingActivities	8000000	USD
CY2020	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	10685000	USD
CY2019	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	2241000	USD
CY2018	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	-0	USD
CY2020	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-45000	USD
CY2019	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-14000	USD
CY2018	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-107000	USD
CY2020	caty	Accretion Amortization Of Investments AccretionAmortizationOfInvestments	58131000	USD
CY2019	caty	Accretion Amortization Of Investments AccretionAmortizationOfInvestments	39898000	USD
CY2018	caty	Accretion Amortization Of Investments AccretionAmortizationOfInvestments	40871000	USD
CY2020	us-gaap	Marketable Securities Gain Loss MarketableSecuritiesGainLoss	1695000	USD
CY2019	us-gaap	Marketable Securities Gain Loss MarketableSecuritiesGainLoss	211000	USD
CY2018	us-gaap	Marketable Securities Gain Loss MarketableSecuritiesGainLoss	22000	USD
CY2020	caty	Other Noncash Interest OtherNoncashInterest	0	USD
CY2019	caty	Other Noncash Interest OtherNoncashInterest	0	USD
CY2018	caty	Other Noncash Interest OtherNoncashInterest	-1576000	USD
CY2020	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-8617000	USD
CY2019	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-3834000	USD
CY2018	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-3018000	USD
CY2020	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-1148000	USD
CY2019	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	5736000	USD
CY2018	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-2787000	USD
CY2020	us-gaap	Employee Benefits And Share Based Compensation Noncash EmployeeBenefitsAndShareBasedCompensationNoncash	6406000	USD
CY2019	us-gaap	Employee Benefits And Share Based Compensation Noncash EmployeeBenefitsAndShareBasedCompensationNoncash	7350000	USD
CY2018	us-gaap	Employee Benefits And Share Based Compensation Noncash EmployeeBenefitsAndShareBasedCompensationNoncash	7974000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	21247000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-6163000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	13984000	USD
CY2020	us-gaap	Business Combination Bargain Purchase Gain Recognized Amount BusinessCombinationBargainPurchaseGainRecognizedAmount	-0	USD
CY2019	us-gaap	Business Combination Bargain Purchase Gain Recognized Amount BusinessCombinationBargainPurchaseGainRecognizedAmount	-0	USD
CY2018	us-gaap	Business Combination Bargain Purchase Gain Recognized Amount BusinessCombinationBargainPurchaseGainRecognizedAmount	340000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-18948000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	21061000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	13848000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	319955000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	434979000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	336538000	USD
CY2020	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-0	USD
CY2019	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-0	USD
CY2018	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-5000000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	434165000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	770206000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	497787000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	734485000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	296721000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	447773000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	117249000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	293849000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	99899000	USD
CY2020	us-gaap	Proceeds From Sale Of Trading Securities Heldforinvestment ProceedsFromSaleOfTradingSecuritiesHeldforinvestment	3112000	USD
CY2019	us-gaap	Proceeds From Sale Of Trading Securities Heldforinvestment ProceedsFromSaleOfTradingSecuritiesHeldforinvestment	2829000	USD
CY2018	us-gaap	Proceeds From Sale Of Trading Securities Heldforinvestment ProceedsFromSaleOfTradingSecuritiesHeldforinvestment	0	USD
CY2020	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	840000	USD
CY2019	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	1815000	USD
CY2018	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	5430000	USD
CY2020	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	1680000	USD
CY2019	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	975000	USD
CY2018	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	11265000	USD
CY2020	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	583136000	USD
CY2019	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	1147019000	USD
CY2018	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	1125623000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	5778000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	7133000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	6670000	USD
CY2020	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	4308000	USD
CY2019	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	2822000	USD
CY2018	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	3820000	USD
CY2020	caty	Net Increase In Investment In Affordable Housing Investing And Alternative Energy Partnerships NetIncreaseInInvestmentInAffordableHousingInvestingAndAlternativeEnergyPartnerships	79119000	USD
CY2019	caty	Net Increase In Investment In Affordable Housing Investing And Alternative Energy Partnerships NetIncreaseInInvestmentInAffordableHousingInvestingAndAlternativeEnergyPartnerships	52697000	USD
CY2018	caty	Net Increase In Investment In Affordable Housing Investing And Alternative Energy Partnerships NetIncreaseInInvestmentInAffordableHousingInvestingAndAlternativeEnergyPartnerships	66574000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-242204000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1381674000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1134327000	USD
CY2020	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	1417310000	USD
CY2019	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	989942000	USD
CY2018	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	1012284000	USD
CY2020	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	0	USD
CY2019	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	0	USD
CY2018	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	-100000000	USD
CY2020	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	1450000000	USD
CY2019	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	4355000000	USD
CY2018	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	5130000000	USD
CY2020	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	1970000000	USD
CY2019	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	4215000000	USD
CY2018	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	5030000000	USD
CY2020	us-gaap	Payments Of Dividends PaymentsOfDividends	98688000	USD
CY2019	us-gaap	Payments Of Dividends PaymentsOfDividends	99131000	USD
CY2018	us-gaap	Payments Of Dividends PaymentsOfDividends	83428000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	23593000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	36301000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	42648000	USD
CY2020	us-gaap	Proceeds From Short Term Debt ProceedsFromShortTermDebt	0	USD
CY2019	us-gaap	Proceeds From Short Term Debt ProceedsFromShortTermDebt	25683000	USD
CY2018	us-gaap	Proceeds From Short Term Debt ProceedsFromShortTermDebt	0	USD
CY2020	us-gaap	Repayments Of Short Term Debt RepaymentsOfShortTermDebt	25683000	USD
CY2019	us-gaap	Repayments Of Short Term Debt RepaymentsOfShortTermDebt	-0	USD
CY2018	us-gaap	Repayments Of Short Term Debt RepaymentsOfShortTermDebt	-0	USD
CY2020	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	7663000	USD
CY2019	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	81065000	USD
CY2018	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	23040000	USD
CY2020	us-gaap	Proceeds From Issuance Of Common Stock Dividend Reinvestment Plan ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan	9777000	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock Dividend Reinvestment Plan ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan	3366000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock Dividend Reinvestment Plan ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan	2822000	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	0	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	0	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	838000	USD
CY2020	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	1911000	USD
CY2019	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	2311000	USD
CY2018	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	3550000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	749549000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	940183000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	863278000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	593778000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	600290000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	827300000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-6512000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	65489000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	534801000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	1421078000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	593778000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	600290000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	162434000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	182527000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	116524000	USD
CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	45371000	USD
CY2019	us-gaap	Income Taxes Paid IncomeTaxesPaid	61548000	USD
CY2018	us-gaap	Income Taxes Paid IncomeTaxesPaid	65866000	USD
CY2020	caty	Net Change In Unrealized Holding Loss Gain On Securities Available For Sale Net Of Tax NetChangeInUnrealizedHoldingLossGainOnSecuritiesAvailableForSaleNetOfTax	6486000	USD
CY2019	caty	Net Change In Unrealized Holding Loss Gain On Securities Available For Sale Net Of Tax NetChangeInUnrealizedHoldingLossGainOnSecuritiesAvailableForSaleNetOfTax	23479000	USD
CY2018	caty	Net Change In Unrealized Holding Loss Gain On Securities Available For Sale Net Of Tax NetChangeInUnrealizedHoldingLossGainOnSecuritiesAvailableForSaleNetOfTax	-7949000	USD
CY2020	us-gaap	Change In Unrealized Gain Loss On Fair Value Hedging Instruments1 ChangeInUnrealizedGainLossOnFairValueHedgingInstruments1	-3478000	USD
CY2019	us-gaap	Change In Unrealized Gain Loss On Fair Value Hedging Instruments1 ChangeInUnrealizedGainLossOnFairValueHedgingInstruments1	-3171000	USD
CY2018	us-gaap	Change In Unrealized Gain Loss On Fair Value Hedging Instruments1 ChangeInUnrealizedGainLossOnFairValueHedgingInstruments1	1525000	USD
CY2020	caty	Transfers To Other Real Estate Owned From Loans Held For Investment TransfersToOtherRealEstateOwnedFromLoansHeldForInvestment	0	USD
CY2019	caty	Transfers To Other Real Estate Owned From Loans Held For Investment TransfersToOtherRealEstateOwnedFromLoansHeldForInvestment	860000	USD
CY2018	caty	Transfers To Other Real Estate Owned From Loans Held For Investment TransfersToOtherRealEstateOwnedFromLoansHeldForInvestment	5476000	USD
CY2020	us-gaap	Transfer Of Loans Held For Sale To Portfolio Loans1 TransferOfLoansHeldForSaleToPortfolioLoans1	0	USD
CY2019	us-gaap	Transfer Of Loans Held For Sale To Portfolio Loans1 TransferOfLoansHeldForSaleToPortfolioLoans1	75285000	USD
CY2018	us-gaap	Transfer Of Loans Held For Sale To Portfolio Loans1 TransferOfLoansHeldForSaleToPortfolioLoans1	0	USD
CY2020Q4	caty	Percentage Of Subsidiaries Common Securities Owned By Parent Company PercentageOfSubsidiariesCommonSecuritiesOwnedByParentCompany	1	pure
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<i>Use of Estimates. </i>The preparation of the Consolidated Financial Statements in accordance with GAAP requires management of the Company to make several estimates and assumptions relating to the reported amount of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the Consolidated Financial Statements and the reported amounts of revenues and expenses during the period. Actual results could differ from those estimates. The significant estimates subject to change relate to the allowance for loan losses.
CY2020	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<i>Concentrations. </i>The Bank was incorporated in California and started its business from California. Therefore, loans originated, and deposits solicited were mainly from California. As of <em style="font: inherit;"> December 31, 2020, </em>gross loans were primarily comprised of 48.3% of commercial mortgage loans, 26.5% of residential mortgage loans, and 18.1% of commercial loans. As of <em style="font: inherit;"> December 31, 2020, </em>approximately 52% of the Bank’s residential mortgages were for properties located in California.
CY2020Q4	caty	Gross Loans Comprised Of Commercial Mortgage Loans Percentage GrossLoansComprisedOfCommercialMortgageLoansPercentage	0.483	pure
CY2020Q4	caty	Residential Mortgages Properties Percentage ResidentialMortgagesPropertiesPercentage	0.265	pure
CY2020Q4	caty	Gross Loans Comprised Of Commercial Loans Percentage GrossLoansComprisedOfCommercialLoansPercentage	0.181	pure
CY2020Q4	us-gaap	Federal Home Loan Bank Stock FederalHomeLoanBankStock	17300000	USD
CY2019Q4	us-gaap	Federal Home Loan Bank Stock FederalHomeLoanBankStock	18100000	USD
CY2020Q4	caty	Federal Home Loan Bank Stock Shares FederalHomeLoanBankStockShares	172500
CY2020Q4	caty	Minimum Stock Requirement On Outstanding Federal Home Loan Bank Borrowings Shares MinimumStockRequirementOnOutstandingFederalHomeLoanBankBorrowingsShares	150000
CY2020Q4	us-gaap	Restricted Cash RestrictedCash	9300000	USD
CY2020Q4	caty	Maximum Loan Size Portfolio Stratification Homogenous Portfolio MaximumLoanSizePortfolioStratificationHomogenousPortfolio	500000	USD
CY2019Q4	us-gaap	Margin Deposit Assets MarginDepositAssets	17700000	USD
CY2020	caty	Average Reserve Balances Required To Be Maintained With Federal Bank AverageReserveBalancesRequiredToBeMaintainedWithFederalBank	60000	USD
CY2019	caty	Average Reserve Balances Required To Be Maintained With Federal Bank AverageReserveBalancesRequiredToBeMaintainedWithFederalBank	110000	USD
CY2020	caty	Average Excess Balances Maintained With Federal Reserve Bank AverageExcessBalancesMaintainedWithFederalReserveBank	874800000	USD
CY2019	caty	Average Excess Balances Maintained With Federal Reserve Bank AverageExcessBalancesMaintainedWithFederalReserveBank	199000000.0	USD
CY2020Q4	us-gaap	Margin Deposit Assets MarginDepositAssets	34700000	USD
CY2019Q4	us-gaap	Restricted Cash RestrictedCash	18900000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	1019230000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	18779000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	1459000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1036550000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	1443730000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	9852000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	1740000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1451842000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	131974000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	132026000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	54820000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	54688000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	190440000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	194029000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	641996000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	655807000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	1019230000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1036550000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	117200000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	293800000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	734500000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	296700000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	1700000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	0	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	583000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	372000	USD
CY2020Q4	caty	Temporarily Impaired Securities As Percentage Of Investment Securities TemporarilyImpairedSecuritiesAsPercentageOfInvestmentSecurities	0.179	pure
CY2020	caty	Percentage Of Unrealized Losses For Securities With Unrealized Losses For Less Than Twelve Months PercentageOfUnrealizedLossesForSecuritiesWithUnrealizedLossesForLessThanTwelveMonths	0.003	pure
CY2020	caty	Percentage Of Unrealized Losses For Securities With Unrealized Losses For Greater Than Twelve Months PercentageOfUnrealizedLossesForSecuritiesWithUnrealizedLossesForGreaterThanTwelveMonths	0.021	pure
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	1500000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	137572000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	423000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	48295000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	1036000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	185867000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	1459000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	144339000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	231000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	349366000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	1509000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	493705000	USD
CY2019	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	24	pure
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	1740000	USD
CY2020Q4	caty	Pledged Investment Securities PledgedInvestmentSecurities	22700000	USD
CY2019Q4	caty	Pledged Investment Securities PledgedInvestmentSecurities	20100000	USD
CY2020	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-1100000	USD
CY2019	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	5700000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	23700000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	28000000.0	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	15644396000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	15075481000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	166538000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	123224000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	2494000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	626000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	15475364000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	14951631000	USD
CY2020Q4	us-gaap	Servicing Asset ServicingAsset	173500000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	43952000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	47263000	USD
CY2020	us-gaap	Loans And Leases Receivable Related Parties Additions LoansAndLeasesReceivableRelatedPartiesAdditions	23102000	USD
CY2019	us-gaap	Loans And Leases Receivable Related Parties Additions LoansAndLeasesReceivableRelatedPartiesAdditions	19036000	USD
CY2020	us-gaap	Loans And Leases Receivable Related Parties Proceeds LoansAndLeasesReceivableRelatedPartiesProceeds	15766000	USD
CY2019	us-gaap	Loans And Leases Receivable Related Parties Proceeds LoansAndLeasesReceivableRelatedPartiesProceeds	22347000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	51288000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	43952000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	95400000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	75900000	USD
CY2020	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	91400000	USD
CY2019	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	102600000	USD
CY2020	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	2400000	USD
CY2019	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	2100000	USD
CY2020Q4	caty	Percentage Of Charge Off To Contractual Balances For Impaired Loans PercentageOfChargeOffToContractualBalancesForImpairedLoans	0.071	pure
CY2019Q4	caty	Percentage Of Charge Off To Contractual Balances For Impaired Loans PercentageOfChargeOffToContractualBalancesForImpairedLoans	0.021	pure
CY2020Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	58816000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	53578000	USD
CY2020	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	5417000	USD
CY2020	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	5417000	USD
CY2020	caty	Financing Receivables Impaired Troubled Debt Restructuring Specific Reserve FinancingReceivablesImpairedTroubledDebtRestructuringSpecificReserve	0	USD
CY2020	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	5	pure
CY2020	us-gaap	Financing Receivables Impaired Troubled Debt Restructuring Write Down FinancingReceivablesImpairedTroubledDebtRestructuringWriteDown	0	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	41315000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	35540000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	49842000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	41827000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	6429000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	41626000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	40319000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	3236000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	108658000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	95405000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	6429000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	82941000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	75859000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	3236000	USD
CY2020	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	91353000	USD
CY2019	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	102583000	USD
CY2018	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	122596000	USD
CY2020	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	2394000	USD
CY2019	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	2084000	USD
CY2018	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	3166000	USD
CY2020	caty	Nonaccrual Portfolio Loans NonaccrualPortfolioLoans	67684000	USD
CY2019	caty	Nonaccrual Portfolio Loans NonaccrualPortfolioLoans	40523000	USD
CY2018	caty	Nonaccrual Portfolio Loans NonaccrualPortfolioLoans	41815000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	67684000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	216542000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	15427854000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	15644396000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	4982000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	40523000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	131462000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	14944019000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	15075481000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	6409000	USD
CY2019	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	25979000	USD
CY2019	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	21916000	USD
CY2019	caty	Financing Receivables Impaired Troubled Debt Restructuring Specific Reserve FinancingReceivablesImpairedTroubledDebtRestructuringSpecificReserve	2190000	USD
CY2019	us-gaap	Financing Receivables Impaired Troubled Debt Restructuring Write Down FinancingReceivablesImpairedTroubledDebtRestructuringWriteDown	4063000	USD
CY2018	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	34	pure
CY2018	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	29130000	USD
CY2018	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	29130000	USD
CY2018	caty	Financing Receivables Impaired Troubled Debt Restructuring Specific Reserve FinancingReceivablesImpairedTroubledDebtRestructuringSpecificReserve	1518000	USD
CY2018	us-gaap	Financing Receivables Impaired Troubled Debt Restructuring Write Down FinancingReceivablesImpairedTroubledDebtRestructuringWriteDown	0	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	15644396000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	15075481000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	6429000	USD
CY2020Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	95405000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	160109000	USD
CY2020Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	15548991000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	166538000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	15644396000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	3236000	USD
CY2019Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	75859000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	119988000	USD
CY2019Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	14999622000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	123224000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	15075481000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	122391000	USD
CY2019	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-7000000	USD
CY2019	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	6997000	USD
CY2019	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	14830000	USD
CY2019	caty	Financing Receivable Allowance For Credit Losses Net Charge Offs FinancingReceivableAllowanceForCreditLossesNetChargeOffs	7833000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	123224000	USD
CY2019Q4	caty	Reserve To Impaired Loans ReserveToImpairedLoans	3236000	USD
CY2019Q4	caty	Reserve To Non Impaired Loans ReserveToNonImpairedLoans	119988000	USD
CY2019Q4	caty	Reserve For Off Balance Sheet Credit Commitments ReserveForOffBalanceSheetCreditCommitments	3855000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	123224000	USD
CY2020	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	57500000	USD
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	21996000	USD
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	7810000	USD
CY2020	caty	Financing Receivable Allowance For Credit Losses Net Charge Offs FinancingReceivableAllowanceForCreditLossesNetChargeOffs	-14186000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	166538000	USD
CY2020Q4	caty	Reserve To Impaired Loans ReserveToImpairedLoans	6429000	USD
CY2020Q4	caty	Reserve To Non Impaired Loans ReserveToNonImpairedLoans	160109000	USD
CY2020Q4	caty	Reserve For Off Balance Sheet Credit Commitments ReserveForOffBalanceSheetCreditCommitments	5880000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	123224000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	122391000	USD
CY2017Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	123279000	USD
CY2020	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	57500000	USD
CY2019	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-7000000	USD
CY2018	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-4500000	USD
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	21996000	USD
CY2019	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	6997000	USD
CY2018	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	3206000	USD
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	7810000	USD
CY2019	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	14830000	USD
CY2018	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	6818000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	166538000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	123224000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	122391000	USD
CY2020Q4	caty	Investments In Affordable Housing And Alternative Energy Partnerships InvestmentsInAffordableHousingAndAlternativeEnergyPartnerships	309000000.0	USD
CY2019Q4	caty	Investments In Affordable Housing And Alternative Energy Partnerships InvestmentsInAffordableHousingAndAlternativeEnergyPartnerships	308700000	USD
CY2020Q4	caty	Affordable Housing Investments AffordableHousingInvestments	279981000	USD
CY2019Q4	caty	Affordable Housing Investments AffordableHousingInvestments	276506000	USD
CY2020Q4	caty	Other Borrowings From Consolidating Affordable Housing Equity Interest OtherBorrowingsFromConsolidatingAffordableHousingEquityInterest	23714000	USD
CY2019Q4	caty	Other Borrowings From Consolidating Affordable Housing Equity Interest OtherBorrowingsFromConsolidatingAffordableHousingEquityInterest	29022000	USD
CY2020Q4	caty	Other Liabilities From Affordablehousing Unfunded Commitments OtherLiabilitiesFromAffordablehousingUnfundedCommitments	103060000	USD
CY2019Q4	caty	Other Liabilities From Affordablehousing Unfunded Commitments OtherLiabilitiesFromAffordablehousingUnfundedCommitments	114541000	USD
CY2020Q4	caty	Alternative Energy Tax Credit Partnership Investments Net AlternativeEnergyTaxCreditPartnershipInvestmentsNet	29035000	USD
CY2019Q4	caty	Alternative Energy Tax Credit Partnership Investments Net AlternativeEnergyTaxCreditPartnershipInvestmentsNet	32175000	USD
CY2020	caty	Increase In Total Assets And Liabilities From Consolidating Affordable Housing Equity Interest IncreaseInTotalAssetsAndLiabilitiesFromConsolidatingAffordableHousingEquityInterest	31400000	USD
CY2019	caty	Increase In Total Assets And Liabilities From Consolidating Affordable Housing Equity Interest IncreaseInTotalAssetsAndLiabilitiesFromConsolidatingAffordableHousingEquityInterest	36300000	USD
CY2020Q4	caty	Alternative Energy Tax Credit Partnership Investments Net AlternativeEnergyTaxCreditPartnershipInvestmentsNet	29000000.0	USD
CY2020Q4	caty	Alternative Energy Tax Credit Partnership Investments Held In Escrow AlternativeEnergyTaxCreditPartnershipInvestmentsHeldInEscrow	9300000	USD
CY2020Q4	caty	Solar Tax Credits Expected To Be Realized SolarTaxCreditsExpectedToBeRealized	9100000	USD
CY2020Q4	caty	Affordable Housing Investments Scheduled Funding For Unfunded Commitments In Next12 Months AffordableHousingInvestmentsScheduledFundingForUnfundedCommitmentsInNext12Months	41602000	USD
CY2020Q4	caty	Affordable Housing Investments Scheduled Funding For Unfunded Commitments In Year Two AffordableHousingInvestmentsScheduledFundingForUnfundedCommitmentsInYearTwo	34696000	USD
CY2020Q4	caty	Affordable Housing Investments Scheduled Funding For Unfunded Commitments In Year Three AffordableHousingInvestmentsScheduledFundingForUnfundedCommitmentsInYearThree	19782000	USD
CY2020Q4	caty	Affordable Housing Investments Scheduled Funding For Unfunded Commitments In Year Four AffordableHousingInvestmentsScheduledFundingForUnfundedCommitmentsInYearFour	1408000	USD
CY2020Q4	caty	Affordable Housing Investments Scheduled Funding For Unfunded Commitments In Year Five AffordableHousingInvestmentsScheduledFundingForUnfundedCommitmentsInYearFive	619000	USD
CY2020Q4	caty	Affordable Housing Investments Scheduled Funding For Unfunded Commitments Thereafter AffordableHousingInvestmentsScheduledFundingForUnfundedCommitmentsThereafter	4953000	USD
CY2020Q4	caty	Other Liabilities From Affordablehousing Unfunded Commitments OtherLiabilitiesFromAffordablehousingUnfundedCommitments	103060000	USD
CY2020	caty	Affordable Housing And Other Tax Credits Recognized AffordableHousingAndOtherTaxCreditsRecognized	23273000	USD
CY2019	caty	Affordable Housing And Other Tax Credits Recognized AffordableHousingAndOtherTaxCreditsRecognized	21523000	USD
CY2018	caty	Affordable Housing And Other Tax Credits Recognized AffordableHousingAndOtherTaxCreditsRecognized	18860000	USD
CY2020	caty	Alternative Energy Tax Credit Usage AlternativeEnergyTaxCreditUsage	29706000	USD
CY2019	caty	Alternative Energy Tax Credit Usage AlternativeEnergyTaxCreditUsage	17786000	USD
CY2018	caty	Alternative Energy Tax Credit Usage AlternativeEnergyTaxCreditUsage	15013000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	205144000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	201463000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	102146000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	97224000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	102998000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	58261000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	69000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	48000	USD
CY2020Q4	us-gaap	Time Deposit Maturities After Year Five TimeDepositMaturitiesAfterYearFive	12000	USD
CY2020Q4	us-gaap	Time Deposits At Carrying Value TimeDepositsAtCarryingValue	6673317000	USD
CY2020Q4	us-gaap	Deposit Liabilities Accrued Interest DepositLiabilitiesAccruedInterest	8500000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	104239000	USD
CY2020	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	7000000.0	USD
CY2019	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	6100000	USD
CY2018	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	6400000	USD
CY2020Q4	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	3365086000	USD
CY2019Q4	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	2871444000	USD
CY2020Q4	us-gaap	Deposits Negotiable Order Of Withdrawal Now DepositsNegotiableOrderOfWithdrawalNOW	1926135000	USD
CY2019Q4	us-gaap	Deposits Negotiable Order Of Withdrawal Now DepositsNegotiableOrderOfWithdrawalNOW	1358152000	USD
CY2020Q4	us-gaap	Deposits Money Market Deposits DepositsMoneyMarketDeposits	3359191000	USD
CY2019Q4	us-gaap	Deposits Money Market Deposits DepositsMoneyMarketDeposits	2260764000	USD
CY2020Q4	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	785672000	USD
CY2019Q4	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	758903000	USD
CY2020Q4	us-gaap	Time Deposits TimeDeposits	6673317000	USD
CY2019Q4	us-gaap	Time Deposits TimeDeposits	7443045000	USD
CY2020Q4	us-gaap	Deposits Deposits	16109401000	USD
CY2019Q4	us-gaap	Deposits Deposits	14692308000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	6507616000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	107311000	USD
CY2019Q4	us-gaap	Deposit Liabilities Accrued Interest DepositLiabilitiesAccruedInterest	22300000	USD
CY2018Q4	us-gaap	Deposit Liabilities Accrued Interest DepositLiabilitiesAccruedInterest	10500000	USD
CY2020	us-gaap	Interest Expense Domestic Deposit Liabilities Demand InterestExpenseDomesticDepositLiabilitiesDemand	2816000	USD
CY2019	us-gaap	Interest Expense Domestic Deposit Liabilities Demand InterestExpenseDomesticDepositLiabilitiesDemand	2371000	USD
CY2018	us-gaap	Interest Expense Domestic Deposit Liabilities Demand InterestExpenseDomesticDepositLiabilitiesDemand	2718000	USD
CY2020	us-gaap	Interest Expense Domestic Deposit Liabilities Money Market InterestExpenseDomesticDepositLiabilitiesMoneyMarket	21574000	USD
CY2019	us-gaap	Interest Expense Domestic Deposit Liabilities Money Market InterestExpenseDomesticDepositLiabilitiesMoneyMarket	21508000	USD
CY2018	us-gaap	Interest Expense Domestic Deposit Liabilities Money Market InterestExpenseDomesticDepositLiabilitiesMoneyMarket	16202000	USD
CY2020	us-gaap	Interest Expense Domestic Deposit Liabilities Savings InterestExpenseDomesticDepositLiabilitiesSavings	1006000	USD
CY2019	us-gaap	Interest Expense Domestic Deposit Liabilities Savings InterestExpenseDomesticDepositLiabilitiesSavings	1432000	USD
CY2018	us-gaap	Interest Expense Domestic Deposit Liabilities Savings InterestExpenseDomesticDepositLiabilitiesSavings	1583000	USD
CY2020	us-gaap	Interest Expense Domestic Deposit Liabilities Time Deposit InterestExpenseDomesticDepositLiabilitiesTimeDeposit	111629000	USD
CY2019	us-gaap	Interest Expense Domestic Deposit Liabilities Time Deposit InterestExpenseDomesticDepositLiabilitiesTimeDeposit	152791000	USD
CY2018	us-gaap	Interest Expense Domestic Deposit Liabilities Time Deposit InterestExpenseDomesticDepositLiabilitiesTimeDeposit	86368000	USD
CY2020	us-gaap	Interest Expense Domestic Deposit Liabilities InterestExpenseDomesticDepositLiabilities	137025000	USD
CY2019	us-gaap	Interest Expense Domestic Deposit Liabilities InterestExpenseDomesticDepositLiabilities	178102000	USD
CY2018	us-gaap	Interest Expense Domestic Deposit Liabilities InterestExpenseDomesticDepositLiabilities	106871000	USD
CY2020Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	0	USD
CY2020	caty	Securities Sold Under Agreements To Repurchase Average Amount Outstanding During The Year SecuritiesSoldUnderAgreementsToRepurchaseAverageAmountOutstandingDuringTheYear	0	USD
CY2019	caty	Securities Sold Under Agreements To Repurchase Average Amount Outstanding During The Year SecuritiesSoldUnderAgreementsToRepurchaseAverageAmountOutstandingDuringTheYear	0	USD
CY2018	caty	Securities Sold Under Agreements To Repurchase Average Amount Outstanding During The Year SecuritiesSoldUnderAgreementsToRepurchaseAverageAmountOutstandingDuringTheYear	49589000	USD
CY2020	caty	Securities Sold Under Agreements To Repurchase Maximum Amount Outstanding At Month End SecuritiesSoldUnderAgreementsToRepurchaseMaximumAmountOutstandingAtMonthEnd	0	USD
CY2019	caty	Securities Sold Under Agreements To Repurchase Maximum Amount Outstanding At Month End SecuritiesSoldUnderAgreementsToRepurchaseMaximumAmountOutstandingAtMonthEnd	0	USD
CY2018	caty	Securities Sold Under Agreements To Repurchase Maximum Amount Outstanding At Month End SecuritiesSoldUnderAgreementsToRepurchaseMaximumAmountOutstandingAtMonthEnd	100000000	USD
CY2020	caty	Securities Sold Under Agreements To Repurchase Amount Outstanding SecuritiesSoldUnderAgreementsToRepurchaseAmountOutstanding	0	USD
CY2019	caty	Securities Sold Under Agreements To Repurchase Amount Outstanding SecuritiesSoldUnderAgreementsToRepurchaseAmountOutstanding	0	USD
CY2018	caty	Securities Sold Under Agreements To Repurchase Amount Outstanding SecuritiesSoldUnderAgreementsToRepurchaseAmountOutstanding	0	USD
CY2020	caty	Securities Sold Under Agreements To Repurchase Interest Rate At Period End SecuritiesSoldUnderAgreementsToRepurchaseInterestRateAtPeriodEnd	0	pure
CY2019	caty	Securities Sold Under Agreements To Repurchase Interest Rate At Period End SecuritiesSoldUnderAgreementsToRepurchaseInterestRateAtPeriodEnd	0	pure
CY2018	caty	Securities Sold Under Agreements To Repurchase Interest Rate At Period End SecuritiesSoldUnderAgreementsToRepurchaseInterestRateAtPeriodEnd	0	pure
CY2004Q4	caty	Threshold For Deferred Bonus ThresholdForDeferredBonus	225000000	USD
CY2004Q4	caty	Amount Of Deferred Bonus Accrued In Other Liabilities AmountOfDeferredBonusAccruedInOtherLiabilities	610000	USD
CY2004Q4	caty	Accrued Interest On Deferred Bonus AccruedInterestOnDeferredBonus	0.070	pure
CY2014Q4	caty	Accrued Interest On Deferred Bonus AccruedInterestOnDeferredBonus	0.0506	pure
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CY2014Q1	caty	Accrued Interest On Deferred Bonus AccruedInterestOnDeferredBonus	0.0502	pure
CY2019Q1	caty	Accrued Interest On Deferred Bonus AccruedInterestOnDeferredBonus	0.0572	pure
CY2020	us-gaap	Interest Expense Other InterestExpenseOther	105000	USD
CY2019	us-gaap	Interest Expense Other InterestExpenseOther	99000	USD
CY2018	us-gaap	Interest Expense Other InterestExpenseOther	92000	USD
CY2020Q4	us-gaap	Accrued Bonuses Current And Noncurrent AccruedBonusesCurrentAndNoncurrent	2100000	USD
CY2019Q4	us-gaap	Accrued Bonuses Current And Noncurrent AccruedBonusesCurrentAndNoncurrent	2000000.0	USD
CY2020Q4	us-gaap	Junior Subordinated Long Term Notes JuniorSubordinatedLongTermNotes	119100000	USD
CY2019Q4	us-gaap	Junior Subordinated Long Term Notes JuniorSubordinatedLongTermNotes	119100000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	2420000000	USD
CY2020	us-gaap	Stockholders Equity Period Increase Decrease StockholdersEquityPeriodIncreaseDecrease	123900000	USD
CY2020	caty	Stockholders Equity Period Increase Decrease Percentage StockholdersEquityPeriodIncreaseDecreasePercentage	0.054	pure
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	2290000000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	228900000	USD
CY2020	us-gaap	Proceeds From Issuance Of Common Stock Dividend Reinvestment Plan ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan	9800000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	5600000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	3000000.0	USD
CY2020	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	23600000	USD
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	98700000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.24
CY2019	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.24
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	38936000	USD
CY2020Q4	us-gaap	Junior Subordinated Notes JuniorSubordinatedNotes	119136000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-2196000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	20943000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	26820000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	36787000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	39466000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	36639000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	34591000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	60409000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	63459000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-3234000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	7464000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	1495000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-6252000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	2361000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	848000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-9486000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	9825000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	2343000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	25105000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	70234000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	65802000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	52899000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	1936000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	2945000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Bonuses DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBonuses	3356000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Bonuses DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBonuses	1293000	USD
CY2020Q4	caty	Deferred Tax Assets Nonaccrual Interest DeferredTaxAssetsNonaccrualInterest	861000	USD
CY2019Q4	caty	Deferred Tax Assets Nonaccrual Interest DeferredTaxAssetsNonaccrualInterest	1005000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Equity Method Investments DeferredTaxAssetsEquityMethodInvestments	1833000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Equity Method Investments DeferredTaxAssetsEquityMethodInvestments	2010000	USD
CY2020Q4	us-gaap	Deferred Tax Assets State Taxes DeferredTaxAssetsStateTaxes	3882000	USD
CY2019Q4	us-gaap	Deferred Tax Assets State Taxes DeferredTaxAssetsStateTaxes	4540000	USD
CY2020Q4	caty	Deferred Tax Assets Unrealized Loss On Interest Rate Swaps DeferredTaxAssetsUnrealizedLossOnInterestRateSwaps	2934000	USD
CY2019Q4	caty	Deferred Tax Assets Unrealized Loss On Interest Rate Swaps DeferredTaxAssetsUnrealizedLossOnInterestRateSwaps	1599000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	9136000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	9473000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	10880000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	14247000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	3864000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	3719000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	91581000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	79767000	USD
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CY2019Q4	caty	Deferred Tax Liabilities Deferred Expense Loan Costs DeferredTaxLiabilitiesDeferredExpenseLoanCosts	9778000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	2709000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	1606000	USD
CY2020Q4	caty	Deferred Tax Liabilities Unrealized Gain On Securities Available For Sale Net DeferredTaxLiabilitiesUnrealizedGainOnSecuritiesAvailableForSaleNet	8712000	USD
CY2019Q4	caty	Deferred Tax Liabilities Unrealized Gain On Securities Available For Sale Net DeferredTaxLiabilitiesUnrealizedGainOnSecuritiesAvailableForSaleNet	5990000	USD
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CY2019Q4	caty	Deferred Tax Liabilities Oreo Installment Sale DeferredTaxLiabilitiesOREOInstallmentSale	-0	USD
CY2020Q4	caty	Deferred Tax Liabilities Dividends On Federal Home Loan Bank Common Stock DeferredTaxLiabilitiesDividendsOnFederalHomeLoanBankCommonStock	979000	USD
CY2019Q4	caty	Deferred Tax Liabilities Dividends On Federal Home Loan Bank Common Stock DeferredTaxLiabilitiesDividendsOnFederalHomeLoanBankCommonStock	978000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	3599000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	3307000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	27290000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	22327000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	64291000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	57440000	USD
CY2020Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	28600000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards Other DeferredTaxAssetsTaxCreditCarryforwardsOther	7500000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards Alternative Minimum Tax DeferredTaxAssetsTaxCreditCarryforwardsAlternativeMinimumTax	1000000.0	USD
CY2020Q4	us-gaap	Income Tax Receivable IncomeTaxReceivable	19500000	USD
CY2019Q4	us-gaap	Income Tax Receivable IncomeTaxReceivable	9600000	USD
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	53333000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210	pure
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CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210	pure
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CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210	pure
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	23602000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.093	pure
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	33276000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.095	pure
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	29750000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.088	pure
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CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.208	pure
CY2019	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	37519000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.107	pure
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CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.102	pure
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CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.003	pure
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CY2018	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	281000	USD
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CY2020	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	228860000	USD
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CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	9384000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	8335000	USD
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CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	23744000	USD
CY2020Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	1068382000	USD
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CY2019Q4	caty	Options Options	908000	USD
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CY2020Q4	caty	Foreign Currency Contract Asset Fair Value Loss Disclosure ForeignCurrencyContractAssetFairValueLossDisclosure	2200000	USD
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CY2019Q4	caty	Foreign Currency Contract Asset Fair Value Loss Disclosure ForeignCurrencyContractAssetFairValueLossDisclosure	1415000	USD
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CY2020Q4	caty	Common Equity Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.0700	pure
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CY2020Q4	caty	Common Equity Tier One Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets CommonEquityTierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets	0.0650	pure
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CY2019Q4	us-gaap	Capital Capital	2086911000	USD
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CY2019Q4	us-gaap	Capital Required For Capital Adequacy CapitalRequiredForCapitalAdequacy	1586821000	USD
CY2019Q4	us-gaap	Capital Required For Capital Adequacy To Risk Weighted Assets CapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.1050	pure
CY2019Q4	us-gaap	Capital Required To Be Well Capitalized CapitalRequiredToBeWellCapitalized	1511258000	USD
CY2019Q4	us-gaap	Capital Required To Be Well Capitalized To Risk Weighted Assets CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets	0.1000	pure
CY2019Q4	us-gaap	Tier One Leverage Capital TierOneLeverageCapital	1959832000	USD
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CY2019Q4	us-gaap	Tier One Leverage Capital Required For Capital Adequacy TierOneLeverageCapitalRequiredForCapitalAdequacy	697976000	USD
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CY2020Q4	us-gaap	Derivative Assets DerivativeAssets	3409000	USD
CY2020Q4	caty	Net Amount Of Derivative Assets Presented In The Balance Sheet NetAmountOfDerivativeAssetsPresentedInTheBalanceSheet	3409000	USD
CY2020Q4	us-gaap	Derivative Asset Fair Value Of Collateral DerivativeAssetFairValueOfCollateral	0	USD
CY2020Q4	caty	Net Amount Of Derivative Assets Presented In The Balance Sheet Not Offset NetAmountOfDerivativeAssetsPresentedInTheBalanceSheetNotOffset	3409000	USD
CY2020Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	28258000	USD
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral	17972000	USD
CY2020Q4	caty	Net Amount Of Derivative Liabilities Presented In The Balance Sheet NetAmountOfDerivativeLiabilitiesPresentedInTheBalanceSheet	10286000	USD
CY2020Q4	us-gaap	Derivative Liability Fair Value Of Collateral DerivativeLiabilityFairValueOfCollateral	-0	USD
CY2019Q4	us-gaap	Derivative Assets DerivativeAssets	2181000	USD
CY2019Q4	caty	Net Amount Of Derivative Assets Presented In The Balance Sheet NetAmountOfDerivativeAssetsPresentedInTheBalanceSheet	2181000	USD
CY2019Q4	us-gaap	Derivative Asset Fair Value Of Collateral DerivativeAssetFairValueOfCollateral	-0	USD
CY2019Q4	caty	Net Amount Of Derivative Assets Presented In The Balance Sheet Not Offset NetAmountOfDerivativeAssetsPresentedInTheBalanceSheetNotOffset	2181000	USD
CY2019Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	14229000	USD
CY2019Q4	caty	Net Amount Of Derivative Liabilities Presented In The Balance Sheet NetAmountOfDerivativeLiabilitiesPresentedInTheBalanceSheet	14229000	USD
CY2019Q4	us-gaap	Derivative Liability Fair Value Of Collateral DerivativeLiabilityFairValueOfCollateral	14229000	USD
CY2020Q4	us-gaap	Interest Income Operating InterestIncomeOperating	167596000	USD
CY2020Q3	us-gaap	Interest Income Operating InterestIncomeOperating	172234000	USD
CY2020Q2	us-gaap	Interest Income Operating InterestIncomeOperating	174008000	USD
CY2020Q1	us-gaap	Interest Income Operating InterestIncomeOperating	186736000	USD
CY2019Q4	us-gaap	Interest Income Operating InterestIncomeOperating	191226000	USD
CY2019Q3	us-gaap	Interest Income Operating InterestIncomeOperating	197831000	USD
CY2019Q2	us-gaap	Interest Income Operating InterestIncomeOperating	192449000	USD
CY2019Q1	us-gaap	Interest Income Operating InterestIncomeOperating	187761000	USD
CY2020Q4	us-gaap	Interest Expense InterestExpense	27776000	USD
CY2020Q3	us-gaap	Interest Expense InterestExpense	34730000	USD
CY2020Q2	us-gaap	Interest Expense InterestExpense	39533000	USD
CY2020Q1	us-gaap	Interest Expense InterestExpense	46425000	USD
CY2019Q4	us-gaap	Interest Expense InterestExpense	50015000	USD
CY2019Q3	us-gaap	Interest Expense InterestExpense	50831000	USD
CY2019Q2	us-gaap	Interest Expense InterestExpense	49070000	USD
CY2019Q1	us-gaap	Interest Expense InterestExpense	44445000	USD
CY2020Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	139820000	USD
CY2020Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	137504000	USD
CY2020Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	134475000	USD
CY2020Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	140311000	USD
CY2019Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	141211000	USD
CY2019Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	147000000	USD
CY2019Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	143379000	USD
CY2019Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	143316000	USD
CY2020Q4	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-5000000	USD
CY2020Q3	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	12500000	USD
CY2020Q2	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	25000000	USD
CY2020Q1	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	25000000	USD
CY2019Q4	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-5000000	USD
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CY2019Q2	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	0	USD
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CY2020Q4	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	144820000	USD
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CY2019Q4	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	146211000	USD
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CY2019Q2	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	143379000	USD
CY2019Q1	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	143316000	USD
CY2020Q4	us-gaap	Noninterest Income NoninterestIncome	11451000	USD
CY2020Q3	us-gaap	Noninterest Income NoninterestIncome	9977000	USD
CY2020Q2	us-gaap	Noninterest Income NoninterestIncome	15606000	USD
CY2020Q1	us-gaap	Noninterest Income NoninterestIncome	5786000	USD
CY2019Q4	us-gaap	Noninterest Income NoninterestIncome	8648000	USD
CY2019Q3	us-gaap	Noninterest Income NoninterestIncome	10388000	USD
CY2019Q2	us-gaap	Noninterest Income NoninterestIncome	12794000	USD
CY2019Q1	us-gaap	Noninterest Income NoninterestIncome	12921000	USD
CY2020Q4	us-gaap	Noninterest Expense NoninterestExpense	75046000	USD
CY2020Q3	us-gaap	Noninterest Expense NoninterestExpense	75997000	USD
CY2020Q2	us-gaap	Noninterest Expense NoninterestExpense	67268000	USD
CY2020Q1	us-gaap	Noninterest Expense NoninterestExpense	65154000	USD
CY2019Q4	us-gaap	Noninterest Expense NoninterestExpense	71192000	USD
CY2019Q3	us-gaap	Noninterest Expense NoninterestExpense	65580000	USD
CY2019Q2	us-gaap	Noninterest Expense NoninterestExpense	69546000	USD
CY2019Q1	us-gaap	Noninterest Expense NoninterestExpense	70970000	USD
CY2020Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	81225000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	58984000	USD
CY2020Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	57813000	USD
CY2020Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	55943000	USD
CY2019Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	83667000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	93808000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	86627000	USD
CY2019Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	85267000	USD
CY2020Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10332000	USD
CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2190000	USD
CY2020Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3492000	USD
CY2020Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	9091000	USD
CY2019Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	16290000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	20973000	USD
CY2019Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	14383000	USD
CY2019Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	18588000	USD
CY2020Q4	us-gaap	Net Income Loss NetIncomeLoss	70893000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	56794000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	54321000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	46852000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	67377000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	72835000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	72244000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	66679000	USD
CY2020Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.89
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.71
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.68
CY2020Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.59
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.85
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.91
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.90
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.83
CY2020Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.89
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.71
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.68
CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.59
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.84
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.91
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.90
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.83

Files In Submission

Name	View Source	Status
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$CATY
CATHAY GENERAL BANCORP Stock $caty

2020 Q4 Form 10-K Financial Statement

#000143774921004299 Filed on March 01, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CATY CATHAY GENERAL BANCORP Stock $caty

2020 Q4 Form 10-K Financial Statement

#000143774921004299 Filed on March 01, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CATY
CATHAY GENERAL BANCORP Stock $caty