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Percentage of Unrealized Losses for Securities with Unrealized Losses for Greater than Twelve Months

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- Definition

Percentage of Unrealized Losses for Securities with Unrealized Losses for Less Than Twelve Months

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No definition available.

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- Definition

Pledged investment securities at carrying value.

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- Definition

Proceeds from maturities repayments and calls of other investment securities.

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No definition available.

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- Definition

Proceeds From Sales and Repayments of Other Investment Securities

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No definition available.

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- Definition

Realized gain from sale and call of other investment securities

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No definition available.

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- Definition

Realized loss from sale and call of other investment securities.

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No definition available.

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Temporarily impaired securities as percentage of investment securities.

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

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Number of investment positions in available-for-sale investments that have been in a continuous unrealized loss position for greater than or equal to a year for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

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No definition available.

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Number of investment positions in available-for-sale investments in a continuous unrealized loss position for less than one year or normal operating cycle, if longer, for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

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No definition available.

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- Definition

For any transfer of securities categorized as held-to-maturity, this item represents the net carrying amount of the transferred security to another category of investments in debt and equity securities (trading or available-for-sale).

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

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This item represents the unrealized gain (loss) related to held-to-maturity securities transferred to another category of investments in debt and equity securities (trading or available-for-sale).

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (c)

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Topic 320

-SubTopic 10

-Section 35

-Paragraph 34

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The cash inflow from the maturity (principal due), prepayment and call (request of early payment) of a loan financed by home mortgage payments classified as held to maturity.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (a)

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The cash inflow from the sale of securities issued by a governmental agency or corporation (for example, GNMA or FHLMC) or by private issuers (for example, banks and mortgage banking enterprises) secured by and repaid from underlying mortgages, which were designated as available for sale when acquired.

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Note 4 - Investment Securities (Details) (USD $)	3 Months Ended	12 Months Ended		3 Months Ended
Note 4 - Investment Securities (Details) (USD $)	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2014
Note 4 - Investment Securities (Details) [Line Items]
Held-to-maturity Securities, Transferred Security, at Carrying Value	$ 722,500,000
Held-to-maturity Securities, Transferred Security, Unrealized Gain (Loss)	40,500,000
Proceeds from Sale of Mortgage Backed Securities (MBS) categorized as Available-for-sale		698,500,000	456,400,000
Proceeds from Maturities, Prepayments and Calls of Mortgage Backed Securities (MBS)		69,700,000	213,200,000
Proceeds From Sales and Repayments of Other Investment Securities		160,500,000	575,400,000
Proceeds from Maturities Repayments and Calls of Other Investment Securities		585,800,000	231,100,000
Realized Gain from Sale and Call of Other Investment Securities		18,000,000	29,000,000
Realized Loss from Sale and Call of Other Investment Securities		11,300,000	1,600,000
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax		11,799,000	69,808,000
Available-for-sale Securities, Amortized Cost Basis		1,324,408,000	1,637,965,000
Temporarily Impaired Securities As Percentage of Investment Securities		66.10%
Percentage of Unrealized Losses for Securities with Unrealized Losses for Less Than Twelve Months		1.10%
Percentage of Unrealized Losses for Securities with Unrealized Losses for Greater than Twelve Months		1.60%
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year		22	19
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year		8	30
Pledged Investment Securities		591,300,000caty_PledgedInvestmentSecurities	926,500,000caty_PledgedInvestmentSecurities
Collateralized Mortgage Backed Securities [Member]
Note 4 - Investment Securities (Details) [Line Items]
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax		6,386,000	64,529,000
Available-for-sale Securities, Amortized Cost Basis		549,296,000	1,010,294,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year		16	7
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year			25
Corporate Bonds Issued By Financial Institutions [Member]
Note 4 - Investment Securities (Details) [Line Items]
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax		1,200,000
Preferred Stock of Government Sponsored Entities [Member]
Note 4 - Investment Securities (Details) [Line Items]
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax		3,733,000
Other than Temporary Impairment Losses, Investments				820,000
Available-for-sale Securities, Amortized Cost Basis		$ 6,276,000	$ 569,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year		2