XML 80 R68.htm IDEA: XBRL DOCUMENT v3.25.2

Note 14 - Financial Derivatives (Details Textual) - USD ($) $ in Thousands		6 Months Ended	12 Months Ended
	May 31, 2014	Jun. 30, 2025	Dec. 31, 2022	Dec. 31, 2024	Jun. 30, 2024
Junior Subordinated Notes, Total	$ 119,100
Derivative Asset, Statement of Financial Position [Extensible Enumeration]				Other Assets
Derivative Liability, Statement of Financial Position [Extensible Enumeration]				Other Liabilities
Interest Rate Swap [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative Outstanding, Notional Amount	$ 119,100	$ 959,300		$ 680,500
Derivative, Notional Amount		28,300		32,700
Derivative Original Maturity (Year)	10 years
Deferred Gain on Early Termination of Derivative			$ 4,000
Interest Rate Swap [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Central Counterparties (CCP) [Member]
Derivative, Notional Amount		0		$ 0
Interest Rate Swap [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative, Notional Amount		626,741			$ 875,117
Interest Rate Contract [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative Outstanding, Notional Amount		48,500
Derivative, Notional Amount		2,000
Interest Rate Contract [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative, Notional Amount		$ 626,700
Interest Rate Contract [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Minimum [Member]
Derivative, Term of Contract (Year)		3 years
Interest Rate Contract [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Maximum [Member]
Derivative, Term of Contract (Year)		10 years
Interest Rate Contract [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Central Counterparties (CCP) [Member]
Derivative, Notional Amount		$ 572,000
Derivative, Loss on Derivative		3,900
Loans Receivable with Partial-term Hedging Designation [Member]
Derivative, Notional Amount		4,500
Hedged Asset, Fair Value Hedge		578,200
Loan, Notational Amount		902,700
Derivative, Gain on Derivative		$ 5,500

X

- Definition

The amount of deferred gain on early termination of derivative recognized.

+ References

No definition available.

+ Details

Name:	caty_DeferredGainOnEarlyTerminationOfDerivative
Namespace Prefix:	caty_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

No definition available.

+ Details

Name:	caty_DerivativeOriginalMaturity
Namespace Prefix:	caty_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Outstanding notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

No definition available.

+ Details

Name:	caty_DerivativeOutstandingNotionalAmount
Namespace Prefix:	caty_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

X

- Definition

The notational amount of a loan.

+ References

No definition available.

+ Details

Name:	caty_LoanNotationalAmount
Namespace Prefix:	caty_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Indicates line item in statement of financial position that includes derivative asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483444/210-20-55-10

+ Details

Name:	us-gaap_DerivativeAssetStatementOfFinancialPositionExtensibleEnumeration
Namespace Prefix:	us-gaap_
Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Amount of increase in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A

+ Details

Name:	us-gaap_DerivativeGainOnDerivative
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Indicates line item in statement of financial position that includes derivative liability.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483444/210-20-55-10

+ Details

Name:	us-gaap_DerivativeLiabilityStatementOfFinancialPositionExtensibleEnumeration
Namespace Prefix:	us-gaap_
Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Amount of decrease in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A

+ Details

Name:	us-gaap_DerivativeLossOnDerivative
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1B

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1A

+ Details

Name:	us-gaap_DerivativeNotionalAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeTermOfContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of asset hedged in fair value hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4EE
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE

+ Details

Name:	us-gaap_HedgedAssetFairValueHedge
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

+ Details

Name:	us-gaap_JuniorSubordinatedNotes
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateSwapMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis=us-gaap_CashFlowHedgingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_HedgingDesignationAxis=us-gaap_DesignatedAsHedgingInstrumentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=caty_CentralCounterpartiesCcpMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis=us-gaap_FairValueHedgingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=caty_LoansReceivableWithPartialTermHedgingDesignationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: