Condensed Consolidated Statements Of Operations And Comprehensive Income (USD $) In Thousands, except Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
INTEREST AND DIVIDEND INCOME
Loans receivable, including loan fees	$ 92,590	$ 95,255	$ 272,940	$ 286,077
Investment securities-taxable	20,304	24,749	65,274	83,788
Investment securities-nontaxable	1,054	19	3,165	195
Federal Home Loan Bank stock	38	77	134	171
Federal funds sold and securities purchased under agreements to resell	33		81
Deposits with banks	360	406	901	1,031
Total interest and dividend income	114,379	120,506	342,495	371,262
INTEREST EXPENSE
Time deposits of $100,000 or more	10,496	12,754	32,115	42,418
Other deposits	4,777	6,603	15,871	23,689
Securities sold under agreements to repurchase	14,840	16,667	45,903	49,469
Advances from Federal Home Loan Bank	2,101	10,090	10,592	30,110
Long-term debt	1,208	1,046	3,630	2,902
Short-term borrowings	4	5	11	5
Total interest expense	33,426	47,165	108,122	148,593
Net interest income before provision for credit losses	80,953	73,341	234,373	222,669
Provision for credit losses	9,000	17,900	25,000	146,900
Net interest income after provision for credit losses	71,953	55,441	209,373	75,769
NON-INTEREST INCOME
Securities gains, net	8,833	484	20,243	9,112
Letters of credit commissions	1,440	1,253	4,113	3,280
Depository service fees	1,341	1,277	4,101	3,870
Other operating income/(loss)	5,213	872	13,449	(180)
Total non-interest income	16,827	3,886	41,906	16,082
NON-INTEREST EXPENSE
Salaries and employee benefits	17,481	14,436	53,411	44,445
Occupancy expense	3,714	2,801	10,709	10,432
Computer and equipment expense	2,139	2,011	6,437	6,132
Professional services expense	4,846	4,460	13,534	14,099
FDIC and State assessments	2,642	4,599	9,864	15,527
Marketing expense	908	749	2,420	2,469
Other real estate owned expense	6,120	453	8,603	5,346
Operations of affordable housing investments , net	2,102	1,166	6,055	5,391
Amortization of core deposit intangibles	1,461	1,484	4,402	4,476
Cost associated with debt redemption	4,540		18,527	909
Other operating expense	2,430	2,722	7,614	10,137
Total non-interest expense	48,383	34,881	141,576	119,363
Income/(loss) before income tax benefit	40,397	24,446	109,703	(27,512)
Income tax expense/(benefit)	14,162	7,023	36,802	(21,418)
Net income/(loss)	26,235	17,423	72,901	(6,094)
Less: net income attributable to noncontrolling interest	151	151	452	452
Net income/(loss) attributable to Cathay General Bancorp	26,084	17,272	72,449	(6,546)
Dividends on preferred stock	(4,111)	(4,098)	(12,323)	(12,286)
Net income/(loss) attributable to common stockholders	21,973	13,174	60,126	(18,832)
Other comprehensive (loss)/income, net of tax
Unrealized holding (loss)/gain arising during the period	(4,753)	290	7,264	29,024
Less: reclassification adjustments included in net income	5,120	203	11,733	3,831
Total other comprehensive (loss)/gain, net of tax	(9,873)	87	(4,469)	25,193
Total comprehensive income	$ 16,211	$ 17,359	$ 67,980	$ 18,647
Net income/(loss) per common share:
Basic	$ 0.28	$ 0.17	$ 0.76	$ (0.25)
Diluted	$ 0.28	$ 0.17	$ 0.76	$ (0.25)
Cash dividends paid per common share	$ 0.01	$ 0.01	$ 0.03	$ 0.03
Average common shares outstanding
Basic	78,640,308	78,520,612	78,628,477	76,584,138
Diluted	78,641,142	78,520,612	78,637,977	76,584,138