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Regulation, restricted on amount of retained earnings available for cash dividends.

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Cash received on warrant transaction.

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Per share amount received for each warrant sold in the transaction.

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Warrants aggregate market price.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

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-Section 50

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-Subparagraph (c)

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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The percentage rate used to calculate dividend payments on preferred stock.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Proceeds from issuance of capital stock which provides for a specific dividend that is paid to the shareholders before any dividends to common stockholders and which takes precedence over common stockholders in the event of liquidation.

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Equity impact of the value of stock bought back by the entity at the exercise price or redemption price.

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Note 13 - Stockholders' Equity and Earnings per Share (Details) (USD $)	0 Months Ended		3 Months Ended			12 Months Ended		24 Months Ended	12 Months Ended
	Dec. 09, 2013	Dec. 05, 2008	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2004	Dec. 31, 2014
Note 13 - Stockholders' Equity and Earnings per Share (Details) [Line Items]
Regulation Restricted On Amount of Retained Earnings Available for Cash Dividends									57,200,000
Proceeds from Issuance of Preferred Stock and Preference Stock		258,000,000
Dividends, Preferred Stock			(2,434,000)us-gaap_DividendsPreferredStock	(2,067,000)us-gaap_DividendsPreferredStock	(5,184,000)us-gaap_DividendsPreferredStock	9,685,000us-gaap_DividendsPreferredStock	16,488,000us-gaap_DividendsPreferredStock
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in Shares)		1,846,374
Class of Warrant or Right, Exercise Price of Warrants or Rights (in Dollars per share)		$ 20.96
Warrants Aggregate Market Price		38,700,000caty_WarrantsAggregateMarketPrice
Sale of Warrant Consideration Received On Transaction	13,100,000
Sale of Warrants Price Per Share (in Dollars per share)	$ 7.20caty_SaleOfWarrantsPricePerShare
Series A Non Cumulative Preferred Stock [Member]
Note 13 - Stockholders' Equity and Earnings per Share (Details) [Line Items]
Proceeds from Issuance of Preferred Stock and Preference Stock								8,600,000
Preferred Stock, Dividend Rate, Percentage								7.00%
Dividends, Preferred Stock						605,000	605,000
Series B Preferred Stock [Member] \| First Five Years [Member]
Note 13 - Stockholders' Equity and Earnings per Share (Details) [Line Items]
Preferred Stock, Dividend Rate, Percentage		5.00%
Series B Preferred Stock [Member] \| After Five Years [Member]
Note 13 - Stockholders' Equity and Earnings per Share (Details) [Line Items]
Preferred Stock, Dividend Rate, Percentage		9.00%
Series B Preferred Stock [Member]
Note 13 - Stockholders' Equity and Earnings per Share (Details) [Line Items]
Proceeds from Issuance of Preferred Stock and Preference Stock		258,000,000
Preferred Stock, Shares Issued (in Shares)		258,000
Stock Redeemed or Called During Period, Value						$ 258,000,000
Equity Option [Member]
Note 13 - Stockholders' Equity and Earnings per Share (Details) [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in Shares)						2,200,000			2,000,000