Represents the collateral discount rates.

No definition available.

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- Definition

The estimated sales cost applied to collateral.

+ References

No definition available.

+ Details

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- Definition

The expected life of warrants.

+ References

No definition available.

+ Details

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- Definition

The fair value measurement with unobservable inputs reconciliation recurring basis warrants.

+ References

No definition available.

+ Details

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- Details

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

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- Definition

Risk-free interest rate assumption used in valuing an instrument.

+ References

+ Details

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- Definition

Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.10(4))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Details

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- Details

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- Details

Name:	us-gaap_ClassOfWarrantOrRightAxis=caty_WarrantsOutstandingMember
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- Details

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Note 11 - Fair Value Measurements (Details) (USD $)	3 Months Ended
Note 11 - Fair Value Measurements (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Note 11 - Fair Value Measurements (Details) [Line Items]
Fair Value Measurement With Unobservable Inputs, Reconciliation Recurring Basis Warrants (in Dollars)	21,000	$ 27,000
Other Real Estate, Foreclosed Assets, and Repossessed Assets (in Dollars)	30,799,000	31,477,000
Warrants Outstanding [Member] \| Minimum [Member]
Note 11 - Fair Value Measurements (Details) [Line Items]
Fair Value Assumptions, Risk Free Interest Rate	0.57%
Fair Value Assumptions, Expected Volatility Rate	10.90%
Warrants Outstanding [Member] \| Maximum [Member]
Note 11 - Fair Value Measurements (Details) [Line Items]
Fair Value Assumptions, Risk Free Interest Rate	1.40%
Fair Value Assumptions, Expected Volatility Rate	15.00%
Net of Estimated Disposal Costs [Member]
Note 11 - Fair Value Measurements (Details) [Line Items]
Other Real Estate, Foreclosed Assets, and Repossessed Assets (in Dollars)			$ 30,800,000	$ 31,500,000
Accounts Receivable Collateral [Member]
Note 11 - Fair Value Measurements (Details) [Line Items]
Collateral Discount Rates	55.00%
Inventory Collateral [Member]
Note 11 - Fair Value Measurements (Details) [Line Items]
Collateral Discount Rates	65.00%
Minimum [Member]
Note 11 - Fair Value Measurements (Details) [Line Items]
Expected Life of Warrants	1 year
Estimated Sales Cost Applied to Collateral	3.00%
Maximum [Member]
Note 11 - Fair Value Measurements (Details) [Line Items]
Expected Life of Warrants	5 years
Estimated Sales Cost Applied to Collateral	6.00%