East West Bancorp (EWBC) 10-K 2 Mar 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2014	Jan. 31, 2015	Jun. 30, 2014
Document and Entity Information
Entity Registrant Name	EAST WEST BANCORP INC
Entity Central Index Key	1069157
Document Type	10-K
Document Period End Date	31-Dec-14
Amendment Flag	FALSE
Current Fiscal Year End Date	-19
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$4,967,770,786
Entity Common Stock, Shares Outstanding		143,583,710
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY

CONSOLIDATED_BALANCE_SHEETS

CONSOLIDATED BALANCE SHEETS (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
ASSETS
Cash and cash equivalents	$1,039,885	$895,820
Short-term investments	338,714	257,473
Securities purchased under resale agreements	1,225,000	1,300,000	[1]
Investment securities available-for-sale, at fair value	2,626,365	2,733,797
Loans held for sale	45,950	204,970
Non-covered loans (net of allowance for loan losses of $258,174 in 2014 and $241,930 in 2013)	19,994,081	15,412,715
Covered loans (net of allowance for loan losses of $3,505 in 2014 and $7,745 in 2013)	1,474,189	2,187,898
Total loans receivable, net	21,468,270	17,600,613
FDIC indemnification asset, net		74,708
Other real estate owned, net	27,612	18,900
Other real estate owned covered, net	4,499	21,373
Total other real estate owned	32,111	40,273
Investment in Federal Home Loan Bank stock, at cost	31,239	62,330
Investment in Federal Reserve Bank stock, at cost	54,451	48,333
Investment in affordable housing partnerships, net	178,652	164,776
Premises and equipment (net of accumulated depreciation of $85,409 in 2014 and $69,768 in 2013)	180,900	177,710
Premiums on deposits acquired, net	45,309	46,920
Goodwill	469,433	337,438
Other assets	1,001,770	784,907
TOTAL	28,738,049	24,730,068
Customer deposit accounts:
Noninterest-bearing	7,381,030	5,821,899
Interest-bearing	16,627,744	14,591,019
Total deposits	24,008,774	20,412,918
Securities sold under repurchase agreements	795,000	995,000
Payable to FDIC, net	96,106
Federal Home Loan Bank advances	317,241	315,092
Long-term debt	225,848	226,868
Accrued expenses and other liabilities	444,512	415,965
Total liabilities	25,887,481	22,365,843
COMMITMENTS AND CONTINGENCIES (Note 15)
STOCKHOLDERS' EQUITY
Common stock, $0.001 par value, 200,000,000 shares authorized; 163,772,218 and 163,098,008 shares issued in 2014 and 2013, respectively; 143,582,229 and 137,630,896 shares outstanding in 2014 and 2013, respectively.	164	163
Additional paid in capital	1,677,767	1,571,670
Retained earnings	1,598,598	1,360,130
Treasury stock, at cost-20,189,989 shares in 2014 and 25,467,112 shares in 2013	-430,198	-537,279
Accumulated other comprehensive (loss) income, net of tax	4,237	-30,459
Total stockholders' equity	2,850,568	2,364,225
TOTAL	$28,738,049	$24,730,068
[1]	Of the $1.40 billion resale agreements as of December 31, 2013, $100.0 million was recorded in cash and cash equivalents and $1.3 billion was recorded in securities under resale agreements in the consolidated balance sheet.

CONSOLIDATED_BALANCE_SHEETS_Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
ASSETS
Non-covered loans, allowance for loan losses	$258,174	$241,930
Covered loans, allowance for loan losses	3,505	7,745
Premises and equipment, accumulated depreciation	$85,409	$69,768
STOCKHOLDERS' EQUITY
Common stock, par value (in dollars per share)	$0.00	$0.00
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	163,772,218	163,098,008
Common stock, shares outstanding	143,582,229	137,630,896
Treasury stock, shares	20,189,989	25,467,112

CONSOLIDATED_STATEMENTS_OF_INC

CONSOLIDATED STATEMENTS OF INCOME (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
INTEREST AND DIVIDEND INCOME
Loans receivable, including fees	$1,059,205	$979,394	$945,530
Investment securities	44,684	43,846	58,184
Securities purchased under resale agreements	20,323	21,236	20,392
Investment in Federal Home Loan Bank and Federal Reserve Bank stock	6,272	6,869	4,673
Due from banks and short-term investments	23,214	17,340	22,316
Total interest and dividend income	1,153,698	1,068,685	1,051,095
INTEREST EXPENSE
Customer deposit accounts	65,486	63,496	75,895
Federal Home Loan Bank advances	4,116	4,173	6,248
Securities sold under repurchase agreements	38,395	41,381	46,166
Long-term debt	4,823	3,436	3,855
Other borrowings		6	4
Total interest expense	112,820	112,492	132,168
Net interest income before provision for loan losses	1,040,878	956,193	918,927
Provision for loan losses on non-covered loans	44,125	18,336	60,168
Provision for loan losses on covered loans	5,033	4,028	5,016
Net interest income after provision for loan losses	991,720	933,829	853,743
NONINTEREST (LOSS) INCOME
Impairment loss on investment securities			-5,165
Less: Noncredit-related impairment loss recorded in other comprehensive income			5,066
Net impairment loss on investment securities recognized in earnings			-99
Changes in FDIC indemnification asset and receivable/payable	-201,417	-228,585	-122,251
Branch fees	37,866	32,036	30,906
Net gains on sales of investment securities	10,851	12,089	757
Letters of credit fees and commissions	25,941	22,116	19,104
Ancillary loan fees	10,616	9,368	8,831
Foreign exchange income	11,381	12,658	7,166
Net gains on sales of loans	39,132	7,750	17,045
Dividend and other investment income	5,464	993	-439
Other commission and fee income	29,419	20,400	16,349
Other operating income	19,033	18,707	17,013
Total noninterest loss	-11,714	-92,468	-5,618
NONINTEREST EXPENSE
Compensation and employee benefits	231,838	175,906	171,374
Occupancy and equipment expense	63,815	56,641	55,475
Amortization of investments in affordable housing partnerships and other tax credit investments	75,660	27,268	18,058
Amortization of premiums on deposits acquired	10,204	9,365	10,906
Deposit insurance premiums and regulatory assessments	21,922	16,550	14,130
Loan related expenses	3,438	12,520	14,987
Other real estate owned (income) expense	-3,591	-1,128	22,349
Legal expense	53,018	31,718	25,441
Data processing	15,888	9,095	9,231
Other operating expenses	92,359	77,576	80,582
Total noninterest expense	564,551	415,511	422,533
INCOME BEFORE TAXES	415,455	425,850	425,592
PROVISION FOR INCOME TAXES	72,972	130,805	143,942
NET INCOME	342,483	295,045	281,650
PREFERRED STOCK DIVIDENDS		3,428	6,857
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS	$342,483	$291,617	$274,793
EARNINGS PER SHARE AVAILABLE TO COMMON STOCKHOLDERS
BASIC (in dollars per share)	$2.39	$2.11	$1.92
DILUTED (in dollars per share)	$2.38	$2.10	$1.89
WEIGHTED AVERAGE NUMBER OF SHARES OUTSTANDING
BASIC (in shares)	142,952	137,342	141,457
DILUTED (in shares)	143,563	139,574	147,175
DIVIDENDS DECLARED PER COMMON SHARE (in dollars per share)	$0.72	$0.60	$0.40

CONSOLIDATED_STATEMENTS_OF_COM

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$342,483	$295,045	$281,650
Other comprehensive income (loss), net of tax:
Net change in unrealized gains (losses) on investment securities available-for-sale	34,714	-35,181	42,429
Noncredit-related impairment loss on securities			-2,938
Foreign currency translation adjustments			-900
Net change in unrealized (losses) gains on other investments	-18	53	18
Other comprehensive income (loss)	34,696	-35,128	38,609
COMPREHENSIVE INCOME	$377,179	$259,917	$320,259

CONSOLIDATED_STATEMENTS_OF_CHA

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (USD $)	Additional Paid In Capital Preferred Stock	Common Stock	Additional Paid In Capital Common Stock	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Total
In Thousands, unless otherwise specified
BALANCE at Dec. 31, 2011	$83,027	$157	$1,443,883	$934,617	($116,001)	($33,940)	$2,311,743
Increase (Decrease) in Stockholders' Equity
Net income				281,650			281,650
Other comprehensive income (loss)						38,609	38,609
Stock compensation costs			12,668				12,668
Tax benefit from stock compensation plans, net			462				462
Issuance of 655,301, 323,737 and 336,031 shares of common stock pursuant to various stock compensation plans and agreements for the year ended December 31, 2014, 2013 and 2012 respectively			3,821				3,821
Issuance of 18,909, 19,998 and 26,151 shares pursuant to Director retainer fee for the year ended December 31, 2014, 2013 and 2012 respectively			570				570
Cancellation of 20,017, 65,686 and 190,634 shares of common stock due to forfeitures of issued restricted stock for the year ended December 31, 2014, 2013 and 2012 respectively			3,335		-3,335
285,953, 508,518 and 137,258 shares of restricted stock surrendered due to employee tax liability for the year ended December 31, 2014, 2013 and 2012 respectively					-3,012		-3,012
Preferred stock dividends				-6,857			-6,857
Common stock dividends				-57,582			-57,582
Purchase of 8,026,807 and 9,068,105 shares of treasury stock pursuant to the Stock Repurchase Program for year ended December 31, 2013 and 2012 respectively					-199,950		-199,950
BALANCE at Dec. 31, 2012	83,027	157	1,464,739	1,151,828	-322,298	4,669	2,382,122
Increase (Decrease) in Stockholders' Equity
Net income				295,045			295,045
Other comprehensive income (loss)						-35,128	-35,128
Stock compensation costs			13,548				13,548
Tax benefit from stock compensation plans, net			5,522				5,522
Issuance of 655,301, 323,737 and 336,031 shares of common stock pursuant to various stock compensation plans and agreements for the year ended December 31, 2014, 2013 and 2012 respectively			3,054				3,054
Issuance of 18,909, 19,998 and 26,151 shares pursuant to Director retainer fee for the year ended December 31, 2014, 2013 and 2012 respectively			630				630
Cancellation of 20,017, 65,686 and 190,634 shares of common stock due to forfeitures of issued restricted stock for the year ended December 31, 2014, 2013 and 2012 respectively			1,156		-1,156
285,953, 508,518 and 137,258 shares of restricted stock surrendered due to employee tax liability for the year ended December 31, 2014, 2013 and 2012 respectively					-13,833		-13,833
Preferred stock dividends				-3,428			-3,428
Common stock dividends				-83,315			-83,315
Conversion of 85,710 shares of Series A preferred stock into 5,594,080 shares of common stock	-83,027	6	83,021
Purchase of 8,026,807 and 9,068,105 shares of treasury stock pursuant to the Stock Repurchase Program for year ended December 31, 2013 and 2012 respectively					-199,992		-199,992
BALANCE at Dec. 31, 2013		163	1,571,670	1,360,130	-537,279	-30,459	2,364,225
Increase (Decrease) in Stockholders' Equity
Net income				342,483			342,483
Other comprehensive income (loss)						34,696	34,696
Stock compensation costs			13,883				13,883
Tax benefit from stock compensation plans, net			6,513				6,513
Issuance of 655,301, 323,737 and 336,031 shares of common stock pursuant to various stock compensation plans and agreements for the year ended December 31, 2014, 2013 and 2012 respectively		1	6,793				6,794
Issuance of 18,909, 19,998 and 26,151 shares pursuant to Director retainer fee for the year ended December 31, 2014, 2013 and 2012 respectively			630				630
Cancellation of 20,017, 65,686 and 190,634 shares of common stock due to forfeitures of issued restricted stock for the year ended December 31, 2014, 2013 and 2012 respectively			379		-379
285,953, 508,518 and 137,258 shares of restricted stock surrendered due to employee tax liability for the year ended December 31, 2014, 2013 and 2012 respectively					-10,326		-10,326
Common stock dividends				-104,015			-104,015
Issuance of 5,583,093 shares pursuant to MetroCorp acquisition			73,044		117,786		190,830
Warrant acquired pursuant to MetroCorp acquisition			4,855				4,855
BALANCE at Dec. 31, 2014		$164	$1,677,767	$1,598,598	($430,198)	$4,237	$2,850,568

CONSOLIDATED_STATEMENTS_OF_CHA1

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Issuance of shares of common stock pursuant to various stock compensation plans and agreements, shares	655,301	323,737	336,031
Issuance of shares pursuant to Director retainer fee, shares	18,909	19,998	26,151
Cancellation of common stock due to forfeitures of issued restricted stock, shares	20,017	65,686	190,634
Restricted stock surrendered due to employee tax liability, shares	285,953	508,518	137,258
Purchase of treasury stock pursuant to the Stock Repurchase Program, shares		8,026,807	9,068,105
Issuance of shares pursuant to MetroCorp acquisition, shares	5,583,093
Common stock issued on conversion of convertible preferred stock		5,594,080
Series A Preferred Stock
Conversion of Series A preferred stock, shares		85,710

CONSOLIDATED_STATEMENTS_OF_CAS

CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$342,483	$295,045	$281,650
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	127,625	101,169	82,536
(Accretion) of discount and amortization of premiums, net	-184,318	-245,665	-233,607
Changes in FDIC indemnification asset and receivable/payable	201,417	228,585	122,251
Stock compensation costs	13,883	13,548	12,668
Deferred tax expenses	-154,612	-45,028	-12,650
Tax benefit from stock compensation plans, net	-6,513	-5,522	-462
Provision for loan losses	49,158	22,364	65,184
Impairment on other real estate owned	2,923	3,849	16,035
Net gain on sales of investment securities, loans and other assets	-64,039	-30,224	-28,165
Originations and purchases of loans held for sale	-92,475	-99,688	-103,059
Proceeds from sales and paydowns/payoffs in loans held for sale	288,706	44,627	25,516
Net (payments to) proceeds from FDIC shared-loss agreements	-1,343	55,826	76,094
Net change in accrued interest receivable and other assets	-88,901	20,526	-35,065
Net change in accrued expenses and other liabilities	-38,586	69,581	15,086
Other net operating activities	-2,510	-3,148	3,514
Total adjustments	50,415	130,800	5,876
Net cash provided by operating activities	392,898	425,845	287,526
CASH FLOWS FROM INVESTING ACTIVITIES
Acquisitions, net of cash paid	138,465
Net (increase) decrease in:
Loans	-3,396,728	-2,458,694	-337,685
Short-term investments	-81,241	108,905	-304,544
Securities purchased under resale agreements	-125,000	150,000	-663,566
Purchases of:
Investment securities available-for-sale	-960,135	-1,316,764	-1,835,823
Loans receivable	-20,783	-680,821	-461,878
Premises and equipment	-11,853	-88,108	-10,280
Investments in affordable housing partnerships and other tax credit investments	-87,925	-42,149	-57,831
Proceeds from sale of:
Investment securities available-for-sale	623,689	663,569	1,230,134
Loans originated for investment	856,434	370,171	414,878
Other real estate owned	70,936	64,312	100,547
Premises and equipment	2,343	6,061	18,914
Repayments, maturities and redemptions of investment securities available-for-sale	554,742	444,057	1,119,098
Redemption of Federal Home Loan Bank stock	33,801	44,945	29,622
Surrender of life insurance policies	49,480
Other net investing activities	-6,118	-330	-491
Net cash used in investing activities	-2,359,893	-2,734,846	-758,905
Net increase (decrease) in:
Deposits	2,277,007	2,103,564	856,352
Short-term borrowings		-20,000	-5,208
Securities sold under repurchase agreements	-25,000
Proceeds from:
Increase in long-term borrowings		100,000
Issuance of common stock pursuant to various stock plans and agreements	6,794	3,054	3,821
Payment for:
Repayment of FHLB advances	-10,000		-100,857
Modification of Federal Home Loan Bank advances			-48,190
Repayment of long-term debt	-30,310	-10,310	-75,000
Repurchase of vested shares due to employee tax liability	-10,326	-13,833	-3,012
Repurchase of shares of treasury stock pursuant to the Stock Repurchase Plan		-199,992	-199,950
Cash dividends	-103,618	-86,290	-64,218
Tax benefit from stock compensation plans, net	6,513	5,522	462
Net cash provided by financing activities	2,111,060	1,881,715	364,200
Effect of exchange rate changes on cash and cash equivalents			-900
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	144,065	-427,286	-108,079
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	895,820	1,323,106	1,431,185
CASH AND CASH EQUIVALENTS, END OF YEAR	1,039,885	895,820	1,323,106
Cash paid during the year for:
Interest	112,695	112,169	136,760
Income tax payments, net of refunds	321,177	142,980	183,398
Noncash investing and financing activities:
Loans transferred to loans held for sale, net	837,389	97,065	144,131
Transfers to other real estate owned	47,547	43,989	81,605
Conversion of preferred stock to common stock		83,027
Loans to facilitate sales of other real estate owned	2,000	139	6,380
Loans to facilitate sales of loans			1,018
Issuance of common stock related to acquisitions	$190,830

SUMMARY_OF_OPERATIONS_AND_SIGN

SUMMARY OF OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 31, 2014
SUMMARY OF OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES
SUMMARY OF OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES	NOTE 1 — SUMMARY OF OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES
	OPERATIONS SUMMARY
	East West Bancorp, Inc. (referred to herein on an unconsolidated basis as “East West” and on a consolidated basis as the “Company”) is a registered bank holding company that offers a full range of banking services to individuals and small to mid-size businesses through its subsidiary bank, East West Bank and its subsidiaries (“East West Bank” or the “Bank”). The Bank is the Company’s principal asset. As of December 31, 2014, the Bank operates over 130 locations in the United States markets of California, Georgia, Nevada, New York, Massachusetts, Texas and Washington. The Bank’s presence includes five full-service branches in the Greater China, located in Hong Kong, two in Shanghai including one in the Shanghai Pilot Free Trade Zone, Shantou and Shenzhen. The Bank also has five representative offices in Greater China located in Beijing, Chongqing, Guangzhou, Xiamen and Taiwan.
	The Bank focuses on commercial lending, including commercial real estate (“CRE”) loans, commercial business loans and trade finance loans. The Bank also provides financing for residential loans including single-family loans, home equity lines of credit (“HELOCs”) and multifamily loans. In addition, the Bank provides financing for construction development loans. The Bank’s revenues are derived from providing financing for residential and CRE and business customers, as well as investing activities. Funding for lending and investing activities is obtained through acceptance of customer deposits, Federal Home Loan Bank (“FHLB”) advances and other borrowing activities.
	SIGNIFICANT ACCOUNTING POLICIES
	Basis of Presentation — The consolidated financial statements are prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and general practices within the banking industry. The following is a summary of significant principles used in the preparation of the accompanying consolidated financial statements. To prepare the consolidated financial statements in conformity with GAAP, management must make estimates based on conditions that affect the reported amounts of assets and liabilities as of the date of the consolidated financial statements and income and expenses during the reporting period and the related disclosures. Actual results could differ from those estimates.
	Principles of Consolidation — The consolidated financial statements include the accounts of East West Bancorp, Inc., and its wholly owned subsidiaries, East West Bank and East West Insurance Services, Inc. Intercompany transactions and accounts have been eliminated in consolidation. East West also has six wholly owned subsidiaries that are statutory business trusts (the “Trusts”). In accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 810, the Trusts are not consolidated into the accounts of East West Bancorp, Inc.
	Cash and Cash Equivalents — Cash and cash equivalents include cash on hand, cash items in transit, cash due from other financial institutions, money-market funds, and other short-term investments with original maturities up to 90 days. Short-term investments included in cash and cash equivalents are short-term bank placements and short-term securities purchased under resale agreements, recorded at cost, which approximates market.
	Short-term Investments — Short-term investments include interest-bearing deposits in other banks and other short-term investments with original maturities greater than 90 days and less than one year.
	Securities Purchased Under Resale Agreements and Sold Under Agreements to Repurchase — The Company’s securities purchased under resale agreements (“resale agreements”) and securities sold under agreements to repurchase (“repurchase agreements”) are transacted under legally enforceable master repurchase agreements that give the Company, in the event of default by the counterparty, the right to liquidate securities held and to offset receivables and payables with the same counterparty. The Company nets repurchase and resale transactions with the same counterparty on the consolidated balance sheet where it has a legally enforceable master netting agreement and when the transactions are eligible for netting under ASC 210-20-45, Balance Sheet—Offsetting. The counterparties to these agreements are nationally recognized financial institutions that meet credit eligibility criteria. Collateral pledged consists of securities that are not recognized on the consolidated balance sheets. Collateral accepted includes securities that are not recognized on the consolidated balance sheets against the related collateralized liability. Collateral accepted or pledged in resale and repurchase agreements with other financial institutions also may be sold or re-pledged by the secured party, but is usually delivered to and held by third party trustees. The Company enters into resale agreements with terms that range from one day to several years. Resale agreements that are short-term in nature, or have terms of up to 90 days, are included in cash and cash equivalents.
	Investment Securities Available-for-Sale — The Company holds debt securities and marketable equity securities in its investment portfolio, classified as available-for-sale investments and reported at fair value. Unrealized gains and losses, after applicable income taxes, are reported in accumulated other comprehensive income.
	Amortization of premiums and accretion of discounts on investment securities are recorded as yield adjustments on such securities using the effective interest method. The specific identification method is used for purposes of determining cost in computing realized gains and losses on investment securities sold.
	Available-for-sale debt and marketable equity securities in unrealized loss positions are analyzed as part of the Company’s ongoing assessment of other-than-temporary impairment (“OTTI”). In determining whether an impairment is other than temporary, the Company considers the severity and duration of the decline in fair value, the length of time expected for recovery, the financial condition of the issuer, changes in the securities’ ratings and other qualitative factors, as well as whether the Company either plans to sell the security or it is more-likely-than-not that it will be required to sell the security before recovery of the amortized cost. If the impairment of the available-for-sale debt security is credit-related, an OTTI loss is recorded in earnings. For available-for-sale debt securities, the non-credit-related impairment loss is recognized in accumulated other comprehensive income. If the Company intends to sell an available-for-sale debt security or believes it will more-likely-than-not be required to sell a security, the Company records the full amount of the impairment loss as an OTTI loss. Available-for-sale marketable equity securities are carried at fair value with net unrealized gains and losses included in accumulated other comprehensive income on an after-tax basis. If there is an other-than-temporary decline in the fair value of any individual available-for-sale marketable equity security, the cost basis is reduced and the Company reclassifies the associated net unrealized loss out of accumulated other comprehensive income with a corresponding charge to the consolidated income statement.
	Loans Held for Sale — Loans held for sale are mainly comprised of student loans carried at the lower of cost or fair value using the aggregate method. Origination fees on loans held for sale, net of certain costs of processing and closing the loans, are deferred until the time of sale and are included in the computation of the gain or loss from the sale of the related loans. A valuation allowance is established if the fair value of such loans is lower than their cost, with a corresponding charge to noninterest income.
	Loans Receivable — Loans receivable that the Company has the intent and ability to hold for the foreseeable future, or until maturity, are stated at their outstanding principal, reduced by an allowance for loan losses and net of deferred loan fees or costs on originated loans and unamortized premiums or discounts on purchased loans. Nonrefundable fees and direct costs associated with the origination or purchase of loans are deferred and netted against outstanding loan balances. The deferred net loan fees and costs are recognized in interest income as an adjustment to yield over the loan term using the effective interest method. Discounts or premiums on purchased loans are accreted or amortized to interest income using the effective interest method over the remaining period to contractual maturity adjusted for anticipated prepayments. Interest on loans is calculated using the simple‑interest method on daily balances of the principal amounts outstanding. Accrual of interest is discontinued on a loan when management believes, after considering economic and business conditions and collection efforts, that the borrower’s financial condition is such that full collection of principal or interest becomes uncertain, regardless of the length of past due status. Generally, loans are placed on nonaccrual status when they become 90 days past due. When interest accrual is discontinued, all unpaid accrued interest recognized in interest income is reversed. Interest payments received on nonaccrual loans are reflected as a reduction of principal and not as interest income. A loan is returned to accrual status when the borrower has demonstrated a satisfactory payment trend subject to management’s assessment of the borrower’s ability to repay the loan.
	Allowance for Loan Losses — The allowance for loan losses is established as management’s estimate of probable losses inherent in the loan portfolio. The allowance is increased by the provision for loan losses and decreased by charge-offs when management believes the uncollectability of a loan is confirmed. Subsequent recoveries, if any, are credited to the allowance. The allowance for loan losses is evaluated on a regular basis by management and is based on management’s periodic review of the collectability of the loans in light of historical experience, the nature and volume of the loan portfolio, adverse situations that may affect the borrower’s ability to repay, the estimated value of any underlying collateral and prevailing economic conditions. This evaluation is inherently subjective as it requires estimates that are susceptible to revision as more information becomes available. Additionally, non-classified loans are also considered in the allowance for loan losses calculation and are factored in based on the historical loss experience adjusted for various qualitative factors.
	A loan is considered impaired when, based on current information and events, it is probable that the Company will be unable to collect all scheduled payments of principal or interest due according to the contractual terms of the loan agreement. Factors considered by management in determining and measuring loan impairment include payment status, collateral value, and the probability of collecting scheduled principal and interest payments when due. Loans that experience insignificant payment delays and payment shortfalls generally are not classified as impaired. Management determines the significance of payment delays and payment shortfalls on a case-by-case basis, taking into consideration all of the circumstances surrounding the loan and the borrower, including the length of delay, the reasons for the delay, the borrower’s prior payment record and the amount of the shortfall in relation to the principal and interest owed. Impairment is measured on a loan-by-loan basis for residential, CRE, and commercial and industrial (“C&I”) loans based on the loan’s observable market price or the fair value of the collateral if the loan is collateral dependent, less costs to sell. If the measure of the impaired loan is less than the recorded investment in the loan and the loan is classified as nonperforming and uncollectible, the deficiency is charged off against the allowance for loan losses. In general, consumer loans consist of homogeneous smaller balance loans and are collectively evaluated for impairment.
	Troubled Debt Restructurings — A loan is identified as a troubled debt restructuring (“TDR”) when a modification of the loan terms takes place where the borrower is determined to be experiencing financial difficulties the Company grants a concession to the borrower in the restructuring that it would not otherwise consider. The concessions may be granted in various forms, including a below-market change in the stated interest rate, reduction in loan balance or accrued interest, extension of the maturity date with a stated interest rate lower than the current market rate or note splits with principal forgiveness. A restructuring executed at an interest rate that is at market interest rates is not considered as a TDR. All TDRs are reviewed for impairment on a quarterly basis. For modifications where the Company forgives principal, the entire amount of such principal forgiveness is immediately charged off. Generally, a nonaccrual loan that is restructured would remain on nonaccrual status for a period of six months to demonstrate that the borrower can perform under the restructured terms. However, the borrower’s performance prior to the restructuring, or other significant events at the time of restructuring may be considered in assessing whether the borrower can meet the new terms and may result in the loan remaining on non-accrual status or being returned to accrual status after a shorter performance period. If the borrower’s performance under the new terms is not reasonably assured, the loan remains classified as a nonaccrual loan. Loans classified as TDRs are reported as impaired loans.
	Purchased Credit Impaired Loans — Acquired loans, in accordance with ASC 805, Business Combinations, are recorded at fair value as of acquisition date. Loans purchased with evidence of credit deterioration since origination, purchased credit impaired (“PCI”) loans, for which it is probable that all contractually required payments will not be collected are accounted for under ASC 310-30, Receivables—Loans and Debt Securities Acquired with Deteriorated Credit Quality.
	Under ASC 310-30, loans are recorded at fair value at acquisition date, factoring in credit losses expected to be incurred over the life of the loan. Accordingly, an allowance for loan losses is not carried over or recorded as of the acquisition date. In situations where loans have similar risk characteristics, loans are aggregated into pools to estimate cash flows under ASC 310-30. A pool is accounted for as a single asset with a single interest rate, cumulative loss rate and cash flow expectation.
	The cash flows expected over the life of the loan or pool are estimated using an internal cash flow model that projects cash flows and calculates the carrying value of the loan or pool, book yield, effective interest income and impairment, if any, based on loan or pool level events, respectively. Assumptions as to default rates, loss severity, loss curves and prepayment speeds are utilized to calculate the expected cash flows.
	At acquisition, the excess of the cash flows expected to be collected over the recorded investment is considered to be the accretable yield and is recognized as interest income over the life of the loan or pool. The excess of the contractual cash flows over the cash flows expected to be collected is considered to be the nonaccretable difference. Subsequent to the acquisition date, any increases in expected cash flows over those expected at purchase date in excess of fair value that are significant and probable are adjusted through the accretable yield on a prospective basis. Any subsequent decreases in expected cash flows over those expected at purchase date that are probable are recognized by recording an allowance for loan losses. Any disposals of loans, including sales of loans, payments in full or foreclosures result in the removal of the loan from the ASC 310-30 portfolio at the carrying amount.
	Covered Loans — Loans acquired in an Federal Deposit Insurance Corporation (“FDIC”)-assisted acquisition that are subject to FDIC shared-loss agreements (“shared-loss agreements”) are referred to as covered loans. Covered loans are reported exclusive of the expected cash flow reimbursements expected to be collected from the FDIC. All covered loans are accounted for under ASC 805 and ASC 310-30.
	FDIC Indemnification Asset/Payable to FDIC, net — In conjunction with the FDIC-assisted acquisitions of Washington First International Bank (“WFIB”) and United Commercial Bank (“UCB”), the Bank entered into shared-loss agreements with the FDIC related to covered loans and covered other real estate owned. The FDIC indemnification asset is initially recorded at fair value, based on the discounted value of expected future cash flows under the shared-loss agreement. The Company has elected to account for amounts receivable under the shared-loss agreements as an indemnification asset in accordance with ASC 805. The difference between the present value and the undiscounted cash flows the Company expects to collect from the FDIC is accreted into noninterest income over the life of the FDIC indemnification asset. The FDIC indemnification asset is reviewed on a quarterly basis and adjusted for any changes in expected cash flows based on recent performance and expectations for future performance of the covered portfolio. Any increases in cash flow of the covered loans over those expected will reduce the FDIC indemnification asset and any decreases in cash flow of the covered loans over those expected will increase the FDIC indemnification asset. Over the life of the FDIC indemnification asset, increases and decreases are recorded as adjustments to noninterest income. Due to continued payoffs and improved credit performance of the covered loan portfolio as compared to the Company's original estimates, the expected reimbursement from the FDIC under the shared-loss agreements has decreased and a payable to FDIC, net has been recorded. Additionally, the FDIC proportionately shares recoveries recognized on previously charged off covered loans.
	Other Real Estate Owned — Other real estate owned (“OREO”) represents properties acquired through foreclosure or through full or partial satisfaction of loans, is considered held for sale, and is recorded at the lower of cost or estimated fair value at the time of foreclosure. Loan balances in excess of the fair value of the real estate acquired at the date of foreclosure are charged against the allowance for loan losses. After foreclosure, the real estate is carried at the lower of carrying value or fair value less costs to sell. Subsequent declines in the fair value of OREO below the carrying value are recorded through the use of a valuation allowance by charges to noninterest expense. Any subsequent operating expenses or income of such properties are also charged to noninterest expense. If the OREO is sold within three months of foreclosure, the Company substitutes the value received in the sale (net of costs to sell) for the fair value (less costs to sell). Any adjustment made to the loss originally recognized at the time of foreclosure is then charged against or credited to the allowance for loan losses, if deemed material. Otherwise, any declines in value, after foreclosure, are recorded in noninterest expense as gains or losses from the sale or disposition of the real estate. Gain recognition upon disposition of a property is dependent on the sale having met certain criteria relating to the buyer’s initial investment in the property sold.
	Covered OREO — All OREO acquired in an FDIC-assisted acquisition that are subject to a FDIC shared-loss agreement are referred to as covered OREO. Covered OREO is reported exclusive of the expected cash flow reimbursements the Company expects to collect from the FDIC. Upon transferring covered loan collateral to covered OREO status, acquisition date fair value discounts on the related loan are also transferred to covered OREO. Fair value adjustments on covered OREO result in a reduction of the covered OREO carrying amount through expense and a corresponding increase of the FDIC reimbursement for 80% of the adjustment resulting in income. The net of that expense and income is the non-reimbursed portion or 20% of the estimated loss to the Bank which is the net amount charged against earnings.
	Investment in Affordable Housing Partnerships and Other Tax Credit Investments — The Company records its investments in affordable housing partnerships and other tax credit investments using either the equity method or cost method of accounting. Investments that are recorded using the cost method, are being amortized over the life of the related tax credits. The tax credits are recognized on the consolidated financial statements to the extent they are utilized on the Company’s income tax returns. The investments are reviewed for impairment on an annual basis or on an interim basis if an event occurs that would trigger potential impairment.
	Goodwill and Other Intangible Assets — The Company has goodwill, which represents the excess of the purchase price over the fair value of net assets acquired, as a result of various past acquisitions. Goodwill is not amortized and is reviewed for impairment on an annual basis or on an interim basis if an event occurs or circumstances change that would reduce the fair value of a reporting unit below its carrying value. Premiums on deposits, which represent the intangible value of depositor relationships resulting from deposit liabilities assumed in acquisitions, are amortized over the projected useful lives of the deposits, which is typically 7 to 15 years. Core deposit intangibles are reviewed for impairment whenever events or changes in circumstances indicate that the carrying value may not be recoverable. Impairment on goodwill and premiums on deposits is recognized by writing down the asset to the extent that the carrying value exceeds the estimated fair value.
	Investment in FHLB Stock — As a member of the FHLB of San Francisco, the Bank is required to own common stock in the FHLB of San Francisco based upon the Company’s balance of residential mortgage loans and outstanding FHLB advances. As a result of the acquisition of WFIB in 2010, the Bank also owns common stock in the FHLB of Seattle. FHLB stock is carried at cost and may be sold back to the FHLB at its carrying value. Cash dividends are accrued and reported as dividend income.
	Investment in Federal Reserve Bank Stock — As a member of the Federal Reserve Bank of San Francisco, the Bank is required to maintain stock in the Federal Reserve Bank of San Francisco based on a specified ratio relative to our capital. Federal Reserve Bank stock is carried at cost and may be sold back to the Federal Reserve Bank at its carrying value. Cash dividends are accrued and reported as dividend income.
	Premises and Equipment — The Company’s premises and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation and amortization are computed based on the straight-line method over the estimated useful lives of the various classes of assets. The ranges of useful lives for the principal classes of assets are as follows:
	Buildings and building improvements	25 years
	Furniture, fixtures and equipment	3 to 7 years
	Leasehold improvements	Term of lease or useful life, whichever is shorter
	The Company reviews its long-lived assets for impairment annually or when events or circumstances indicate that the carrying amount of these assets may not be recoverable. An asset is considered impaired when the expected undiscounted cash flows over the remaining useful life is less than the net book value. When impairment is indicated for an asset, the amount of impairment loss is the excess of the net book value over its fair value.
	Long-Term Debt — Long-term debt consists of junior subordinated debt and other long-term debt. The Company has six statutory business trusts whereby the Company is the owner of all the beneficial interests represented by the common securities of the Trusts, and third parties hold the fixed and variable rate capital securities of the Trusts. The purpose of issuing the capital securities was to provide the Company with a cost-effective means of obtaining Tier I capital for regulatory reporting purposes. However, these securities are being phased out of the Tier I capital, a process that commenced in 2013 with phase-out complete by 2016.
	The Trusts are not consolidated by the Company. Junior subordinated debt represents liabilities of the Company to the Trusts and is included in long-term debt on the accompanying consolidated balance sheets.
	Income Taxes — Deferred income taxes are recognized for the tax consequences in future years of differences between the tax bases of assets and liabilities and their financial reporting amounts at each year-end, based on enacted tax laws and statutory tax rates applicable to the periods in which the differences are expected to affect taxable income.
	The Company examines its financial statements, its income tax provision, and its federal and state income tax returns and analyzes its tax positions, including permanent and temporary differences, as well as the major components of income and expense to determine whether a tax benefit is more likely than not to be sustained upon examination by tax authorities. In the event a tax position is not more likely than not to be sustained by the tax authorities, a reserve is established by management. The Company recognizes interest and penalties related to tax positions as part of its provision for income taxes.
	Stock-Based Compensation — The Company issues stock-based compensation to certain employees, officers, and directors and accounts for stock options using the fair value method, which generally results in compensation expense recognition.
	Earnings Per Share — The Company applies the two-class method in computing earnings per share (“EPS”). The Company’s restricted stock, which receives dividends as declared, qualify as participating securities. Restricted stock units granted by the Company are not considered participating securities, as they do not have dividend distribution rights during the vesting period. Basic EPS is computed by dividing net income, net of income allocated to participating securities, by the weighted-average number of common shares outstanding during each period, net of treasury shares and including vested but unissued shares and share units. The computation of diluted EPS reflects the additional dilutive effect of common stock equivalents such as unvested stock awards and stock options.
	Derivatives — As part of the asset and liability management strategy, the Company uses derivative financial instruments to mitigate exposure to interest rate and foreign currency risks. All derivative instruments, including certain derivative instruments embedded in other contracts, are recognized on the consolidated balance sheet at fair value with the changes in fair value reported in earnings.
	The Company’s interest rate swaps on certain certificates of deposit qualify for hedge accounting treatment under ASC 815, Derivatives and Hedging.  The Company documents its hedge relationships, including identification of the hedging instruments and the hedged items, as well as its risk management objectives and strategies for undertaking the hedge transaction at the time the derivative contract is executed. This includes designating the derivative contract as a “fair value hedge” which is a hedge of a recognized asset or liability.  All derivatives designated as fair value hedges are linked to specific hedged items or to groups of specific assets and liabilities on the balance sheet.  Both at inception and quarterly thereafter, the Company assesses whether the derivatives used in hedging transactions are highly effective in offsetting changes in the fair value of the hedged item. Retroactive effectiveness is also assessed as well as the continued expectation that the hedge will remain effective prospectively.  Any ineffective portion of the changes of fair value hedges is recognized immediately in interest expense in the consolidated statements of income.
	The Company discontinues hedge accounting prospectively when (i) a derivative is no longer highly effective in offsetting changes in the fair value, (ii) a derivative expires or is sold, terminated, or exercised, or (iii) the Company determines that designation of a derivative as a hedge is no longer appropriate. If a fair value hedge derivative instrument is terminated or the hedge designation removed, the previous adjustments to the carrying amount of the hedged liability would be subsequently accounted for in the same manner as other components of the carrying amount of that liability. For interest-bearing liabilities, such adjustments would be amortized into earnings over the remaining life of the respective liability.
	The Company also offers various derivative products to clients and enters into derivative transactions in due course. These transactions are not linked to specific Company assets or liabilities in the consolidated balance sheets or to forecasted transactions in a hedge relationship and, therefore, do not qualify for hedge accounting. The contracts are marked-to-market at the end of each reporting period with changes in fair value recorded in the consolidated statements of income.
	Fair Value — Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date and, in many cases, requires management to make a number of significant judgments. Based on the observability of the inputs used in the valuation techniques, the Company classifies its assets and liabilities measured and disclosed at fair value in accordance with a three-level hierarchy (e.g., Level 1, Level 2 and Level 3) established under ASC 820, Fair Value Measurements. In determining the fair value of financial instruments, the Company uses market prices of the same or similar instruments whenever such prices are available. The Company does not use prices involving distressed sellers in determining fair value. If observable market prices are unavailable or impracticable to obtain, then fair value is estimated using modeling techniques such as discounted cash flow analysis. These modeling techniques incorporate management’s assessments regarding assumptions that market participants would use in pricing the asset or the liability, including assumptions about the risks inherent in a particular valuation technique and the risk of nonperformance.
	Reclassifications — Certain items in the consolidated financial statements and notes for the prior years have been reclassified to conform to the 2014 presentation.
	NEW ACCOUNTING PRONOUNCEMENTS ADOPTED
	In July 2013, the FASB issued ASU 2013-11, Income Taxes (Topic 740), Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists. ASU 2013-11 eliminates diversity in practice as it provides guidance on financial statement presentation of an unrecognized tax benefit when a net operating loss (“NOL”) carryforward, a similar tax loss, or a tax credit carryforward exists. The Company adopted this guidance in first quarter 2014 with prospective application to all unrecognized tax benefits that exist at the effective date. ASU 2013-11 did not have a material impact on the Company’s consolidated financial statements.
	RECENT ACCOUNTING PRONOUNCEMENTS
	In January 2014, the FASB issued ASU 2014-01, Investments—Equity Method and Joint Ventures (Topic 323): Accounting for Investments in Qualified Affordable Housing Projects. ASU 2014-10 permits reporting entities to make an accounting policy election to account for their investments in qualified affordable housing projects using the proportional amortization method if certain conditions are met. Under the proportional amortization method, an entity amortizes the initial cost of the investment in proportion to the tax credits and other tax benefits received and recognizes the net investment performance in the income statement as a component of income tax expense (benefit). ASU 2014-10 is effective for interim and annual periods beginning after December 15, 2014 and if elected, should be applied retrospectively to all periods presented. Early adoption is permitted. The Company is currently evaluating the impact on the Company’s consolidated financial statements.
	In January 2014, the FASB issued ASU 2014-04, Receivables—Troubled Debt Restructurings by Creditors (Subtopic 310-40): Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure. ASU 2014-04 clarifies when an in-substance repossession or foreclosure occurs that would require a transfer of mortgage loans collateralized by residential real estate properties to OREO. The standard permits the use of either a modified retrospective or prospective transition method.  ASU 2014-04 is effective for interim and annual periods beginning after December 15, 2014. Early adoption is permitted. The Company does not expect the adoption of this guidance to have a material effect on its consolidated financial statements.
	In May 2014, The FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606). The new guidance replaces existing revenue recognition guidance for contracts to provide goods or services to customers and amends  existing guidance related to recognition of gains and losses on the sale of certain nonfinancial assets such as real estate.  ASC 606 establishes a principles-based approach to recognizing revenue that applies to all contracts other than those covered by other authoritative GAAP guidance. Quantitative and qualitative disclosures regarding the nature, amount, timing and uncertainty of revenue and cash flows are also required.  ASC 606 is effective for interim and annual periods beginning after December 15, 2016 and is applied on either a modified retrospective or full retrospective basis. Early adoption is not permitted. The Company is currently evaluating the impact on its consolidated financial statements.

BUSINESS_COMBINATION

BUSINESS COMBINATION	12 Months Ended
	Dec. 31, 2014
BUSINESS COMBINATION
BUSINESS COMBINATION	NOTE 2 — BUSINESS COMBINATION
	On January 17, 2014, the Company completed the acquisition of MetroCorp Bancshares, Inc. (“MetroCorp”), parent of MetroBank, N.A. and Metro United Bank. MetroCorp, headquartered in Houston, Texas, operated 19 branch locations within Texas and California under its two banks. The Company acquired MetroCorp to further expand its presence, primarily in Texas, within the markets of Houston and Dallas, and in California, within the San Diego market. The purchase consideration was satisfied with two thirds in East West stock and one third in cash. The fair value of the consideration transferred in the acquisition of MetroCorp was $291.4 million, which consisted of 5,583,093 shares of East West common stock fair valued at $190.8 million at the date of acquisition and $89.4 million in cash, $2.4 million of additional cash to MetroCorp stock option holders and a MetroCorp warrant, fair valued at $8.8 million, assumed by the Company.
	The assets acquired and liabilities assumed have been accounted for under the acquisition method of accounting. At the acquisition date, the Company recorded total fair value of assets acquired of $1.70 billion, which included $230.3 million in cash and due from banks, $64.3 million in investment securities available for sale, $2.7 million in FHLB stock, $1.19 billion in loans receivable, $8.6 million in fixed assets, $8.6 million in premiums on deposits acquired, $9.4 million in OREO, $30.0 million in bank owned life insurance (BOLI), $13.0 million in deferred tax assets and $16.7 million in other assets. The total fair value of liabilities acquired was $1.41 billion, which included $1.32 billion in deposits, $10.0 million in FHLB advances, $25.9 million in repurchase agreements, $29.1 million in junior subordinated debt and $22.7 million in other liabilities. The assets and liabilities, both tangible and intangible, were recorded at their estimated fair values as of the January 17, 2014 acquisition date. Goodwill from the acquisition represents the excess of the purchase price over the fair value of the net tangible and intangible assets acquired and is not deductible for tax purposes. The Company recorded $121.0 million of goodwill at the acquisition date. During the fourth quarter of 2014, the Company recorded additional tax and BOLI adjustments of $10.3 million and $0.7 million, respectively related to the MetroCorp acquisition, resulting in an increase to goodwill to $132.0 million.
	The Company has included the financial results of this business combination in the consolidated statements of income beginning on the acquisition date. Supplemental financial information regarding the former MetroCorp operations included in the consolidated statement of income from the date of acquisition through December 31, 2014 has not been separately presented as the operations of MetroCorp have been fully integrated into the Company’s operations and separate records for MetroCorp as a stand-alone business have not been maintained.
	The following table presents the Company's unaudited pro forma results of operations for the periods presented as if the MetroCorp acquisition had been completed on January 1, 2014 and January 1, 2013, respectively. The 2014 unaudited pro forma information combines MetroCorp's 2014 historical results with the Company's 2014 consolidated historical results and includes MetroCorp's results of operations prior to acquisition date, January 17, 2014. The 2013 unaudited pro forma information combines MetroCorp's 2013 historical results with the Company's 2013 consolidated historical results and includes the estimated impact of certain fair value adjustments for the assets acquired and liabilities assumed and merger and acquisition integration costs. The unaudited pro forma information is not necessarily indicative of the Company's future operating results or operating results that would have occurred had the acquisition been completed at the beginning of 2014 and 2013, respectively. No assumptions have been applied to the pro forma results of operations regarding possible revenue enhancements, expense efficiencies or asset dispositions. As a result, actual results will differ from the unaudited pro forma information presented.
		Pro forma
		Year Ended December 31,
		2014		2013
		(In thousands)
	Net interest income and noninterest loss	$	1,028,796	$	934,207
	Net income after tax	$	338,730	$	299,625

FAIR_VALUE_MEASUREMENT_AND_FAI

FAIR VALUE MEASUREMENT AND FAIR VALUE OF FINANCIAL INSTRUMENTS	12 Months Ended
	Dec. 31, 2014
FAIR VALUE MEASUREMENT AND FAIR VALUE OF FINANCIAL INSTRUMENTS
FAIR VALUE MEASUREMENT AND FAIR VALUE OF FINANCIAL INSTRUMENTS	NOTE 3 — FAIR VALUE MEASUREMENT AND FAIR VALUE OF FINANCIAL INSTRUMENTS
	In determining fair value, the Company uses various methods including market and income approaches. Based on these approaches, the Company utilizes certain assumptions that market participants would use in pricing the asset or liability. These inputs can be readily observable, market corroborated, or generally unobservable inputs. The Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs. Based on the observability of the inputs used in the valuation techniques, the Company is required to provide the following information according to the fair value hierarchy noted below. The hierarchy is based on the quality and reliability of the information used to determine fair values. The hierarchy gives the highest priority to quoted prices available in active markets and the lowest priority to data lacking transparency. Financial assets and liabilities carried at fair value will be classified and disclosed in one of the following three categories:
	•	Level 1 — Valuation is based on quoted prices for identical instruments traded in active markets.
	•	Level 2 — Valuation is based on quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations whose inputs are observable and can be corroborated by market data.
	•	Level 3 — Valuation is based on significant unobservable inputs for determining the fair value of assets or liabilities.  These significant unobservable inputs reflect assumptions that market participants may use in pricing the assets or liabilities.
	In determining the appropriate hierarchy levels, the Company performs an analysis of the assets and liabilities that are subject to fair value disclosure.  The following tables present both financial assets and liabilities that are measured at fair value on a recurring basis.  These assets and liabilities are reported on the consolidated balance sheets at their fair values as of December 31, 2014 and December 31, 2013.  Financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to their fair value measurement.  There were no transfers for assets measured on a recurring basis in and out of Level 1, Level 2 or Level 3 during the years ended December 31, 2014 and 2013.
			Assets (Liabilities) Measured at Fair Value on a Recurring Basis as of
			31-Dec-14
			Fair Value Measurements December 31, 2014			Quoted Prices in			Significant			Significant
						Active Markets			Other			Unobservable
						for Identical			Observable			Inputs
						Assets			Inputs			(Level 3)
						(Level 1)			(Level 2)
			(In thousands)
	Investment securities available-for-sale:
	U.S. Treasury securities		$	873,435		$	873,435		$	—		$	—
	U.S. government agency and U.S. government sponsored enterprise debt securities		311,024			—			311,024			—
	U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities:
	Commercial mortgage-backed securities		141,420			—			141,420			—
	Residential mortgage-backed securities		791,088			—			791,088			—
	Municipal securities		250,448			—			250,448			—
	Other residential mortgage-backed securities:
	Investment grade		53,918			—			53,918			—
	Other commercial mortgage-backed securities:
	Investment grade		34,053			—			34,053			—
	Corporate debt securities:
	Investment grade		115,182			—			115,182			—
	Non-investment grade		14,681			—			8,153			6,528
	Other securities		41,116			32,105			9,011			—
	Total investment securities available-for-sale		$	2,626,365		$	905,540		$	1,714,297		$	6,528
	Derivative assets:
	Foreign exchange options		$	6,136		$	—		$	6,136		$	—
	Interest rate swaps and caps		$	41,534		$	—		$	41,534		$	—
	Foreign exchange contracts		$	8,123		$	—		$	8,123		$	—
	Derivative liabilities:
	Interest rate swaps on certificates of deposits		$	(9,922	)	$	—		$	(9,922	)	$	—
	Interest rate swaps and caps		$	(41,779	)	$	—		$	(41,779	)	$	—
	Foreign exchange contracts		$	(9,171	)	$	—		$	(9,171	)	$	—
	Embedded derivative liabilities		$	(3,392	)	$	—		$	—		$	(3,392	)
			Assets (Liabilities) Measured at Fair Value on a Recurring Basis as of
			31-Dec-13
			Fair Value Measurements December 31, 2013			Quoted Prices in			Significant			Significant
						Active Markets			Other			Unobservable
						for Identical			Observable			Inputs
						Assets			Inputs			(Level 3)
						(Level 1)			(Level 2)
			(In thousands)
	Investment securities available-for-sale:
	U.S. Treasury securities		$	491,632		$	491,632		$	—		$	—
	U.S. government agency and U.S. government sponsored enterprise debt securities		394,323			—			394,323			—
	U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities:
	Commercial mortgage-backed securities		178,870			—			178,870			—
	Residential mortgage-backed securities		885,237			—			885,237			—
	Municipal securities		280,979			—			280,979			—
	Other residential mortgage-backed securities:
	Investment grade		46,327			—			46,327			—
	Other commercial mortgage-backed securities:
	Investment grade		51,617			—			51,617			—
	Corporate debt securities:
	Investment grade		309,995			—			309,995			—
	Non-investment grade		15,101			—			8,730			6,371
	Other securities		79,716			—			79,716			—
	Total investment securities available-for-sale		$	2,733,797		$	491,632		$	2,235,794		$	6,371
	Derivative assets:
Foreign exchange options		$	6,290		$	—		$	6,290		$	—
Interest rate swaps and caps		$	28,078		$	—		$	28,078		$	—
Foreign exchange contracts		$	6,181		$	—		$	6,181		$	—
Derivative liabilities:
Interest rate swaps on certificates of deposits		$	(16,906	)	$	—		$	(16,906	)	$	—
Interest rate swaps and caps		$	(26,352	)	$	—		$	(26,352	)	$	—
Foreign exchange contracts		$	(3,349	)	$	—		$	(3,349	)	$	—
Embedded derivative liabilities		$	(3,655	)	$	—		$	—		$	(3,655	)
At each reporting period, all assets and liabilities for which the fair value measurement is based on significant unobservable inputs are classified as Level 3.  The following tables provide a reconciliation of the beginning and ending balances for major asset and liability categories measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the years ended December 31, 2014, 2013, and 2012:
		Year Ended December 31,
		2014						2013						2012
		Corporate Debt			Embedded Derivative			Corporate Debt			Embedded Derivative			Corporate Debt			Embedded Derivative
		Securities:			Liabilities			Securities:			Liabilities			Securities:			Liabilities
		Non-Investment Grade						Non-Investment Grade						Non-Investment Grade
		(In thousands)
Beginning balance		$	6,371		$	(3,655	)	$	4,800		$	(3,052	)	$	2,235		$	(2,634	)
Total gains or (losses) for the period:
Included in earnings(1)		802			263			—			(603		)	(99		)	(418		)
Included in other comprehensive income (unrealized) (2)		2,326			—			1,653			—			2,711			—
Purchases, issues, sales, settlements:
Purchases		—			—			—			—			—			—
Issues		—			—			—			—			—			—
Sales		(2,595		)	—			—			—			—			—
Settlements		(376		)	—			(82		)	—			(47		)	—
Transfer from investment grade to non-investment grade		—			—			—			—			—			—
Transfers in and/or out of Level 3		—			—			—			—			—			—
Ending balance		$	6,528		$	(3,392	)	$	6,371		$	(3,655	)	$	4,800		$	(3,052	)
Changes in unrealized losses included in earnings relating to assets and liabilities held at period-end		$	—		$	(263	)	$	—		$	603		$	99		$	418
-1	Realized gains or losses of corporate debt securities and embedded derivative liabilities are included in net gains on sales of investment securities and other operating expense, respectively, in the consolidated statements of income.
-2	Unrealized gains or losses on investment securities are reported in other comprehensive income (loss), net of tax, in the consolidated statements of comprehensive income.
The following table presents quantitative information about significant unobservable inputs used in the valuation of assets and liabilities measured on a recurring basis classified as Level 3 as of December 31, 2014 and 2013:
		Fair Value			Valuation Technique(s)		Unobservable Input(s)	Range of Inputs		Weighted
		Measurements								Average
		(Level 3)
		($ in thousands)
31-Dec-14
Investment securities available-for-sale:
Corporate debt securities:
Non-investment grade		$	6,528		Discounted cash flow		Constant prepayment rate	0% - 1%		0.73%
							Constant default rate	0.75% - 1.20%		0.87%
							Loss severity	85%		85%
							Discount margin	4.50% - 7.50%		6.94%
Embedded derivative liabilities		$	(3,392	)	Discounted cash flow		Credit risk	0.115% - 0.142%		0.13%
31-Dec-13
Investment securities available-for-sale:
Corporate debt securities:
Non-investment grade		$	6,371		Discounted cash flow		Constant prepayment rate	0% - 1%		0.74%
							Constant default rate	0.75% - 1.20%		0.87%
							Loss severity	85%		85%
							Discount margin	6.50% - 11.50%		9.97%
Embedded derivative liabilities		$	(3,655	)	Discounted cash flow		Credit risk	0.175% - 0.212%		0.20%
Assets measured at fair value on a nonrecurring basis using significant unobservable inputs include certain loans and OREO.  The inputs and assumptions for nonrecurring Level 3 fair value measurements for certain loans and OREO include adjustments to external and internal appraisals for changes in the market, assumptions by appraiser embedded into appraisals, probability weighting of broker price opinions, and management’s adjustments for other relevant factors and market trends.
The following tables present assets measured at fair value on a nonrecurring basis as of December 31, 2014 and 2013:
		Assets Measured at Fair Value on a Nonrecurring Basis as of
		31-Dec-14
		Fair Value			Quoted Prices in			Significant			Significant
		Measurements			Active Markets			Other			Unobservable
					for Identical			Observable			Inputs
					Assets			Inputs			(Level 3)
					(Level 1)			(Level 2)
		(In thousands)
Non-covered impaired loans:
CRE		$	26,089		$	—		$	—		$	26,089
C&I		16,581			—			—			16,581
Residential		25,034			—			—			25,034
Consumer		107			—			—			107
Total non-covered impaired loans		$	67,811		$	—		$	—		$	67,811
Non-covered OREO		$	15,735		$	—		$	—		$	15,735
Covered OREO		$	1,786		$	—		$	—		$	1,786
		Assets Measured at Fair Value on a Nonrecurring Basis as of
		31-Dec-13
		Fair Value			Quoted Prices in			Significant			Significant
		Measurements			Active Markets			Other			Unobservable
					for Identical			Observable			Inputs
					Assets			Inputs			(Level 3)
					(Level 1)			(Level 2)
		(In thousands)
Non-covered impaired loans:
CRE		$	29,559		$	—		$	—		$	29,559
C&I		15,120			—			—			15,120
Residential		12,791			—			—			12,791
Consumer		281			—			—			281
Total non-covered impaired loans		$	57,751		$	—		$	—		$	57,751
Non-covered OREO		$	13,031		$	—		$	—		$	13,031
Covered OREO		$	17,284		$	—		$	—		$	17,284
The following table presents fair value adjustments of certain assets measured on a nonrecurring basis recognized during the years ended and still held as of December 31, 2014, 2013, and 2012:
		Year Ended December 31,
		2014			2013			2012
		(In thousands)
Non-covered impaired loans:
CRE		$	2,196		$	(4,250	)	$	(8,405	)
C&I		(9,169		)	(13,135		)	(14,540		)
Residential		(61		)	(1,378		)	(4,803		)
Consumer		(1		)	(112		)	(264		)
Total non-covered impaired loans		$	(7,035	)	$	(18,875	)	$	(28,012	)
Non-covered OREO		$	(1,573	)	$	(1,438	)	$	(5,122	)
Covered OREO (1)		$	(1,027	)	$	(3,376	)	$	(11,183	)
-1	Covered OREO results from the WFIB and UCB FDIC-assisted acquisitions for which the Company entered into shared-loss agreements with the FDIC whereby the FDIC will reimburse the Company for 80% of eligible losses. As such, the Company’s liability for losses is 20% of the $1.0 million in losses, or $205 thousand, and 20% of the $3.4 million in losses, or $675 thousand, and 20% of the $11.2 million in losses, or $2.2 million for the years ended December 31, 2014, 2013, and 2012, respectively.
The following table presents quantitative information about significant unobservable inputs used in the valuation of assets measured on a nonrecurring basis classified as Level 3 as of December 31, 2014 and 2013:
		Fair Value			Valuation		Unobservable	Range of Inputs		Weighted
		Measurements			Technique(s)		Input(s)			Average
		(Level 3)
		($ in thousands)
31-Dec-14
Non-covered impaired loans		$	11,499		Discounted cash flow		Discount rate	0% - 81%		49%
		$	56,312		Market comparables		Discount rate(1)	0% - 100%		4%
Non-covered OREO		$	15,735		Appraisal		Selling cost	8%		8%
Covered OREO		$	1,786		Appraisal		No Discount
31-Dec-13
Non-covered impaired loans		$	57,751		Market comparables		Discount rate(1)	0% - 100%		13%
Non-covered OREO		$	13,031		Appraisal		Selling cost	8%		8%
Covered OREO		$	17,284		Appraisal		No Discount
(1)Discount rate is adjusted for factors such as liquidation cost of collateral and selling cost.
The following tables present carrying and fair values per the fair value hierarchy of certain financial instruments, excluding those measured at fair value on a recurring basis, as of December 31, 2014 and 2013 were as follows:
		31-Dec-14
		Carrying			Level 1			Level 2			Level 3			Estimated
		Amount												Fair Value
		(In thousands)
Financial assets:
Cash and cash equivalents		$	1,039,885		$	1,039,885		$	—		$	—		$	1,039,885
Short-term investments		$	338,714		$	—		$	338,714		$	—		$	338,714
Securities purchased under resale agreements		$	1,225,000		$	—		$	1,191,060		$	—		$	1,191,060
Loans held for sale		$	45,950		$	—		$	45,950		$	—		$	45,950
Loans receivable, net		$	21,468,270		$	—		$	—		$	20,997,379		$	20,997,379
Investment in Federal Home Loan Bank stock		$	31,239		$	—		$	31,239		$	—		$	31,239
Investment in Federal Reserve Bank stock		$	54,451		$	—		$	54,451		$	—		$	54,451
Accrued interest receivable		$	88,303		$	—		$	88,303		$	—		$	88,303
Financial liabilities:
Customer deposit accounts:
Demand, savings and money market deposits		$	17,896,035		$	—		$	17,896,035		$	—		$	17,896,035
Time deposits		$	6,112,739		$	—		$	—		$	6,095,217		$	6,095,217
Federal Home Loan Bank advances		$	317,241		$	—		$	336,302		$	—		$	336,302
Securities sold under repurchase agreements		$	795,000		$	—		$	870,434		$	—		$	870,434
Accrued interest payable		$	11,303		$	—		$	11,303		$	—		$	11,303
Long-term debt		$	225,848		$	—		$	205,777		$	—		$	205,777
		31-Dec-13
		Carrying			Level 1			Level 2			Level 3			Estimated
		Amount												Fair Value
		(In thousands)
Financial assets:
Cash and cash equivalents		$	895,820		$	895,820		$	—		$	—		$	895,820
Short-term investments		$	257,473		$	—		$	257,473		$	—		$	257,473
Securities purchased under resale agreements		$	1,300,000		$	—		$	1,279,406		$	—		$	1,279,406
Loans held for sale		$	204,970		$	—		$	212,469		$	—		$	212,469
Loans receivable, net		$	17,600,613		$	—		$	—		$	16,741,674		$	16,741,674
Investment in Federal Home Loan Bank stock		$	62,330		$	—		$	62,330		$	—		$	62,330
Investment in Federal Reserve Bank stock		$	48,333		$	—		$	48,333		$	—		$	48,333
Accrued interest receivable		$	116,314		$	—		$	116,314		$	—		$	116,314
Financial liabilities:
Customer deposit accounts:
Demand, savings and money market deposits		$	14,588,570		$	—		$	14,588,570		$	—		$	14,588,570
Time deposits		$	5,824,348		$	—		$	—		$	5,791,659		$	5,791,659
Federal Home Loan Bank advances		$	315,092		$	—		$	308,521		$	—		$	308,521
Securities sold under repurchase agreements		$	995,000		$	—		$	1,134,774		$	—		$	1,134,774
Accrued interest payable		$	11,178		$	—		$	11,178		$	—		$	11,178
Long-term debt		$	226,868		$	—		$	184,415		$	—		$	184,415
The following is a description of the valuation methodologies and significant assumptions used in estimating fair value of financial instruments.
Cash and Cash Equivalents — The carrying amount approximates fair value due to the short-term nature of these instruments. Due to the short-term nature of these instruments, the estimated fair value is classified as Level 1.
Short-Term Investments — The fair value of short-term investments generally approximate their book value due to their short maturities.  Due to the observable nature of the inputs used in deriving the estimated fair value of these instruments, the estimate is classified as Level 2.
Securities Purchased Under Resale Agreements — Securities purchased under resale agreements with original maturities of 90 days or less are included in cash and cash equivalents.  The fair value of securities purchased under resale agreements with original maturities of more than 90 days is estimated by discounting the cash flows based on expected maturities or repricing dates utilizing estimated market discount rates.  Due to the observable nature of the inputs used in deriving the estimated fair value of these instruments, the estimate is classified as Level 2.
Investment Securities Available-for-Sale — When available, the Company uses quoted market prices to determine the fair value of investment securities available-for-sale; such items are classified as Level 1.  Level 1 investment securities mainly include U.S. treasury securities.  The fair values of other investment securities are generally determined by independent external pricing service providers who have experience in valuing these securities and by comparison to and/or average of quoted market prices obtained from independent external brokers. In obtaining such valuation information from third parties, the Company has reviewed the methodologies used to develop the resulting fair values.  The investment securities valued using such methods are classified as Level 2.
The Company’s Level 3 available-for-sale securities are comprised of pooled trust preferred securities. The fair values of these investment securities represent less than 1% of the total available-for-sale investment securities.  The fair values of the pooled trust preferred securities have traditionally been based on the average of at least two quoted market prices obtained from independent external brokers since broker quotes in an active market are given the highest priority. As a result of the continued illiquidity in the pooled trust preferred securities market, it is the Company’s view that current broker prices (which are typically non-binding) on certain pooled trust preferred securities are not representative of the fair value of these securities.  As such, the Company considered what weight, if any, to place on transactions that are not orderly when estimating fair value.
For the pooled trust preferred securities, the fair values were derived based on discounted cash flow analysis (the income method) prepared by management. In order to determine the appropriate discount rate used in calculating fair values derived from the income method for the pooled trust preferred securities, the Company has made assumptions using an exit price approach related to the implied rate of return which have been adjusted for general changes in market rates, estimated changes in credit risk and liquidity risk premium, specific nonperformance, and default experience in the collateral underlying the securities.  Significant increases (decreases) in any of those inputs in isolation would result in a significantly lower (higher) fair value measurement.  Generally, a change in the assumption used for the probability of default is accompanied by a directionally similar change in the assumption used for credit risk and liquidity risk.  The actual Level 3 unobservable assumption rates used as of December 31, 2014 include: constant prepayment rate, constant default rate, loss severity for deferrals/defaults, and discount margin.
Loans Held for Sale — The Company’s loans held for sale are carried at the lower of cost or fair value. These loans are comprised of student loans.  The fair value of loans held for sale is derived from current market prices and comparative current sales. As such, the Company records any fair value adjustments on a nonrecurring basis. Loans held for sale are classified as Level 2.
Non-covered Impaired Loans — The Company evaluates non-covered impaired loans on a nonrecurring basis. The fair value of non-covered impaired loans is measured using the market comparables technique. For CRE loans and C&I loans, the fair value is based on each loan’s observable market price or the fair value of the collateral less cost to sell, if the loan is collateral dependent. The fair value of this collateral is based on third party appraisals or evaluations which are reviewed by the Company’s appraisal department. Updated appraisals and evaluations are obtained on a regular basis or at least annually. Further, on a quarterly basis, all appraisals and evaluations of nonperforming assets are reviewed to assess the current carrying value and to ensure that the current carrying value is appropriate. For certain performing TDRs, the Company utilizes the discounted cash flow technique and applies a discount rate derived from historical data. For residential loans with an unpaid balance below a certain threshold, the Company applies historical loss rates to derive the fair value. The significant unobservable inputs used in the fair value measurement of non-covered impaired loans are discount rates applied based on liquidation cost of collateral and selling cost. Non-covered impaired loans are classified as Level 3.
Loans Receivable, net — The fair value of loans is determined based on a discounted cash flow approach considered for an exit price value. The discount rate is derived from the associated yield curve plus spreads, and reflects the offering rates in the market for loans with similar financial characteristics. No adjustments have been made for changes in credit within any of the loan portfolios. It is management’s opinion that the allowance for loan losses pertaining to performing and nonperforming loans results in a fair value valuation of credit for such loans. Due to the unobservable nature of the inputs used in deriving the estimated fair value of these instruments, the estimate is classified as Level 3.
OREO — The Company’s OREO represents properties acquired through foreclosure or through full or partial satisfaction of loans receivable, which are recorded at estimated fair value less the cost to sell at the time of foreclosure and at the lower of cost or estimated fair value less the cost to sell subsequent to acquisition. The fair values of OREO properties are based on third party appraisals, broker price opinions or accepted written offers. Refer to the “Non-covered Impaired Loans” section above for detailed discussion on the Company’s policy and procedures of appraisals and evaluations. The Company uses the market comparables valuation technique to measure the fair value of OREO properties. The significant unobservable input used is the selling cost. OREO properties are classified as Level 3.
Investment in FHLB Stock and Federal Reserve Bank Stock — The carrying amounts of the Company’s investments in FHLB Stock and Federal Reserve Bank Stock approximate fair value. The valuation of these investments is classified as Level 2.  Ownership of these securities is restricted to member banks and the securities do not have a readily determinable fair value.  Purchases and sales of these securities are at par value.
Accrued Interest Receivable — The carrying amount approximates fair value due to the short-term nature of these instruments. Due to the observable nature of the inputs used in deriving the estimated fair value, these instruments are classified as Level 2.
Foreign Exchange Options — The Company entered into foreign exchange option contracts with major investment firms during the year ended December 31, 2010. The settlement amount is determined based upon the performance of the Chinese currency Renminbi (“RMB”) relative to the U.S. Dollar (“USD”) over the 5-year term of the contracts. The performance amount is computed based on the average quarterly value of the RMB compared to the USD as compared to the initial value. The fair value of these derivative contracts is provided by third parties and is determined based on the change in the RMB and the volatility of the option over the life of the agreement. The option value is derived based on the volatility of the option, interest rate, currency rate and time remaining to maturity. The Company’s consideration of the counterparty’s credit risk resulted in a nominal adjustment to the valuation of the foreign exchange options as of December 31, 2014 and 2013. Due to the observable nature of the inputs used in deriving the fair value of these derivative contracts, the valuation of the option contracts is classified as Level 2.
Interest Rate Swaps and Caps — The Company enters into interest rate swap and cap contracts with institutional counterparties to hedge against interest rate swap and cap products offered to bank customers. These products allow borrowers to lock in attractive intermediate and long-term interest rates by entering into an interest rate swap or cap contract with the Company, resulting in the customer obtaining a synthetic fixed rate loan. The Company also enters into interest rate swap contracts with institutional counterparties to hedge against certificates of deposit issued. This product allows the Company to lock in attractive floating rate funding. The fair value of interest rate swap contracts is based on a discounted cash flow approach. The counterparty’s credit risk is considered in the valuation of interest rate swaps as of December 31, 2014 and 2013. Due to the observable nature of the inputs used in deriving the fair value of these derivative contracts, the valuation of interest rate swaps and caps is classified as Level 2.
Foreign Exchange Contracts — The Company enters into short-term foreign exchange contracts to purchase/sell foreign currencies at set rates in the future. These contracts economically hedge against foreign exchange rate fluctuations.  The Company also enters into contracts with institutional counterparties to hedge against foreign exchange products offered to bank customers. These products allow customers to hedge the foreign exchange risk of their deposits and loans denominated in foreign currencies. The Company assumes minimal foreign exchange rate risk as the contract with the customer and the contract with the institutional party mirror each other. The fair value is determined at each reporting period based on the change in the foreign exchange rate. Given the short-term nature of the contracts, the counterparties’ credit risks are considered nominal and resulted in no adjustments to the valuation of the short-term foreign exchange contracts as of December 31, 2014 and 2013. The valuation of these contracts is classified as Level 2 due to the observable nature of the inputs used in deriving the fair value.
The Company also enters into long-term foreign exchange contracts to purchase/sell foreign currencies at set rates in the future. The fair value is determined at each reporting period based on the change in the foreign exchange rate. The Company’s consideration of the counterparty’s credit risk resulted in no adjustment to the valuation of the long-term foreign exchange contract as of December 31, 2014 and 2013. The valuation of these contracts is classified as Level 2 due to the observable nature of the inputs used in deriving the fair value.
Customer Deposits — The carrying amount approximates fair value for demand and interest checking deposits, savings deposits, and certain money market deposits as the amounts are payable on demand as of the balance sheet date. Due to the observable nature of the inputs used in deriving the estimated fair value, these instruments are classified as Level 2. For time deposits, the fair value is based on the discounted value of contractual cash flows using the rates offered by the Company. Due to the unobservable nature of the inputs used in deriving the estimated fair value of these instruments, the estimate is classified as Level 3.
FHLB Advances — The fair value of FHLB advances is estimated based on the discounted value of contractual cash flows, using rates currently offered by the FHLB of San Francisco for advances with similar remaining maturities at each reporting date. Due to the observable nature of the inputs used in deriving the estimated fair value of these instruments, the estimate is classified as Level 2.
Securities Sold Under Repurchase Agreements — For securities sold under repurchase agreements with original maturities of 90 days or less, the carrying amount approximates fair value due to the short-term nature of these instruments. At December 31, 2014 and December 31, 2013, most of the securities sold under repurchase agreements were long-term in nature and the fair values of securities sold under repurchase agreements were calculated by discounting future cash flows based on expected maturities or repricing dates, utilizing estimated market discount rates, and taking into consideration the call features of each instrument. Due to the observable nature of the inputs used in deriving the estimated fair value of these instruments, the estimate is classified as Level 2.
Accrued Interest Payable — The carrying amount approximates fair value due to the short-term nature of these instruments. Due to the observable nature of the inputs used in deriving the estimated fair value, these instruments are classified as Level 2.
Long-Term Debt — The fair value of long-term debt is estimated by discounting the cash flows through maturity based on current market rates the Company would pay for new issuances. Due to the observable nature of the inputs used in deriving the estimated fair value of these instruments, the estimate is classified as Level 2.
Embedded Derivative Liabilities — During 2010, the Company entered into foreign exchange option contracts with major brokerage firms to economically hedge against foreign exchange fluctuations in certain certificates of deposits available to its customers. These certificates of deposits have a term of 5 years and pay interest based on the performance of the RMB relative to the USD. Under ASC 815, a certificate of deposit that pays interest based on changes in foreign exchange rates is a hybrid instrument with an embedded derivative that must be accounted for separately from the host contract (i.e., the certificate of deposit).
The fair value of these embedded derivatives is based on the discounted cash flow approach.  The liabilities are divided between the portion under FDIC insurance coverage and the non-insured portion.  For the FDIC insured portion the Company applied a risk premium comparable to an agency security risk premium.  For the non-insured portion, the Company considered its own credit risk in determining the valuation by applying a risk premium based on the Company institutional credit rating.  Total credit valuation adjustments on derivative liabilities were nominal for the years ended December 31, 2014 and 2013.   Increases (decreases), if any, of those inputs in isolation would result in a lower (higher) fair value measurement.  The valuation of the embedded derivative liabilities fall within Level 3 of the fair value hierarchy since the significant inputs used in deriving the fair value of these derivative contracts are not directly observable.   The actual Level 3 unobservable input used as of December 31, 2014 was a credit risk adjustment.
The fair value estimates presented herein are based on pertinent information available to management as of each reporting date.  Although the Company is not aware of any factors that would significantly affect the estimated fair value amounts, such amounts have not been comprehensively revalued for purposes of these financial statements since that date, and therefore, current estimates of fair value may differ significantly from the amounts presented herein.

CASH_AND_CASH_EQUIVALENTS_AND_

CASH AND CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS	12 Months Ended
	Dec. 31, 2014
CASH AND CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS
CASH AND CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS	NOTE 4 — CASH AND CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS
	Cash and cash equivalents include cash, amounts due from banks, money-market funds, and other short-term investments with original maturities up to 90 days. Short-term investments include short-term bank placements and short-term securities purchased under resale agreements, recorded at cost, which approximates market.
	The composition of cash and cash equivalents as of December 31, 2014 and 2013 is presented as follows:
		December 31,
		2014		2013
		(In thousands)
	Cash and amounts due from banks	$	944,118	$	693,387
	Cash equivalents:
	Money market funds	—		605
	Other short-term investments	95,767		201,828
	Total cash and cash equivalents	$	1,039,885	$	895,820
	Short-term investments were $338.7 million and $257.5 million which include interest-bearing deposits in other banks of $50.2 million and $60.3 million as of December 31, 2014 and 2013, respectively. These short-term investments have original maturities of greater than 90 days and less than one year.

SECURITIES_PURCHASED_UNDER_RES

SECURITIES PURCHASED UNDER RESALE AGREEMENTS AND SOLD UNDER REPURCHASE AGREEMENTS	12 Months Ended
	Dec. 31, 2014
SECURITIES PURCHASED UNDER RESALE AGREEMENTS AND SOLD UNDER REPURCHASE AGREEMENTS
SECURITIES PURCHASED UNDER RESALE AGREEMENTS AND SOLD UNDER REPURCHASE AGREEMENTS	NOTE 5 — SECURITIES PURCHASED UNDER RESALE AGREEMENTS AND SOLD UNDER REPURCHASE
	AGREEMENTS
	Resale agreements
	Resale agreements are recorded at the amounts at which the securities were acquired. The Company’s policy is to obtain possession of securities purchased under resale agreements that are equal to or greater than the principal amount loaned. The market values of the underlying securities, collateralizing the related receivable of the resale agreements, including accrued interest are monitored. Additional collateral may be requested by the Company from the counterparty when deemed appropriate. Gross resale agreements were $1.43 billion and $1.40 billion as of December 31, 2014 and 2013, respectively. The weighted average interest rates were 1.55% and 1.44% as of December 31, 2014 and 2013, respectively. The maturities of the gross resale agreements are as follows: 2015 — $875.0 million; 2016 and 2017 — $0.0 million; 2018 — $50.0 million; 2019 — $0.0 million; 2020 and thereafter — $500.0 million.
	Repurchase agreements
	Long-term repurchase agreements are accounted for as collateralized financing transactions and recorded at the amounts at which the securities were sold. The collaterals for these agreements are mainly comprised of U.S. government agency and U.S. government sponsored enterprise debt and mortgage-backed securities. The Company may have to provide additional collateral for the repurchase agreements, as necessary. Gross repurchase agreements were $995.0 million as of December 31, 2014 and 2013. The weighted average interest rates were 3.70% and 4.06% as of December 31, 2014 and 2013, respectively. As of December 31, 2014, total gross repurchase agreements that matures during the next five years are as follows: 2015 — $245.0 million; 2016 — $250.0 million; 2017 — $50.0 million; 2018 and 2019— $0.0 million; 2020 and thereafter — $450.0 million.
	Balance Sheet Offsetting
	The Company’s resale agreements and repurchased agreements are transacted under legally enforceable master repurchase agreements that give the Company, in the event of default by the counterparty, the right to liquidate securities held and to offset receivables and payables with the same counterparty. The Company nets repurchase and resale transactions with the same counterparty on the consolidated balance sheet where it has a legally enforceable master netting agreement and when the transactions are eligible for netting under ASC 210-20-45. Collateral pledged consists of securities which are not netted on the consolidated balance sheet against the related collateralized liability. Collateral accepted includes securities that are not recognized on the consolidated balance sheets. Collateral accepted or pledged in resale and repurchase agreements with other financial institutions also may be sold or re-pledged by the secured party, but is usually delivered to and held by the third party trustees.
			As of December 31, 2014
			(In thousands)
			Gross Amounts		Gross Amounts			Net Amounts of			Gross Amounts Not Offset on the
			of Recognized		Offset on the			Assets Presented			Consolidated Balance Sheets
			Assets		Consolidated			on the
					Balance Sheet			Consolidated
	Assets							Balance Sheet			Financial				Collateral				Net Amount
											Instruments				Received
	Resale agreements		$	1,425,000	$	(200,000	)	$	1,225,000		$	(425,000	)	(1)	$	(797,172	)	(2)	$	2,828
			Gross Amounts		Gross Amounts			Net Amounts of			Gross Amounts Not Offset on the
			of Recognized		Offset on the			Liabilities			Consolidated Balance Sheets
			Liabilities		Consolidated			Presented on the
					Balance Sheet			Consolidated
	Liabilities							Balance Sheet			Financial				Collateral				Net Amount
											Instruments				Posted
	Repurchase agreements		$	995,000	$	(200,000	)	$	795,000		$	(425,000	)	(1)	$	(370,000	)	(3)	$	—
			As of December 31, 2013
			(In thousands)
			Gross Amounts		Gross Amounts			Net Amounts of			Gross Amounts Not Offset on the
			of Recognized		Offset on the			Assets Presented			Consolidated Balance Sheets
			Assets		Consolidated			on the
					Balance Sheet			Consolidated
	Assets							Balance Sheet			Financial				Collateral				Net Amount
											Instruments				Received
	Resale agreements		$	1,400,000	$	—		$	1,400,000	(4)	$	(495,000	)	(1)	$	(905,000	)	(2)	$	—
			Gross Amounts		Gross Amounts			Net Amounts of			Gross Amounts Not Offset on the
			of Recognized		Offset on the			Liabilities			Consolidated Balance Sheets
			Liabilities		Consolidated			Presented on the
					Balance Sheet			Consolidated
	Liabilities							Balance Sheet			Financial				Collateral				Net Amount
											Instruments				Posted
	Repurchase agreements		$	995,000	$	—		$	995,000		$	(495,000	)	(1)	$	(500,000	)	(3)	$	—
	-1	Includes financial instruments subject to enforceable master netting arrangements that are not permitted to be offset under ASC 210-20-45 but would be eligible for offsetting to the extent an event of default has occurred.
	-2	Represents the fair value of securities the Company has received under resale agreements, limited for table presentation purposes to the amount of the recognized asset due from each counterparty.
	-3	Represents the fair value of securities the Company has pledged under repurchase agreements, limited for table presentation purposes to the amount of the recognized liability owed to each counterparty.
	-4	Of the $1.40 billion resale agreements as of December 31, 2013, $100.0 million was recorded in cash and cash equivalents and $1.30 billion was recorded in securities under resale agreements in the consolidated balance sheet.

INVESTMENT_SECURITIES

INVESTMENT SECURITIES	12 Months Ended
	Dec. 31, 2014
INVESTMENT SECURITIES
INVESTMENT SECURITIES	NOTE 6 — INVESTMENT SECURITIES
	The following tables present the amortized cost, gross unrealized gains, gross unrealized losses and fair value by major categories of available-for-sale securities:
			Amortized				Gross			Gross			Fair
			Cost				Unrealized			Unrealized			Value
							Gains			Losses
							(In thousands)
	As of December 31, 2014
	Investment securities available-for-sale:
	U.S. Treasury securities		$	873,101			$	1,971		$	(1,637	)	$	873,435
	U.S. government agency and U.S. government sponsored enterprise debt securities		311,927				490			(1,393		)	311,024
	U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities:
	Commercial mortgage-backed securities		140,957				1,056			(593		)	141,420
	Residential mortgage-backed securities		785,412				9,754			(4,078		)	791,088
	Municipal securities		245,408				6,202			(1,162		)	250,448
	Other residential mortgage-backed securities:
	Investment grade (1)		52,694				1,359			(135		)	53,918
	Other commercial mortgage-backed securities:
	Investment grade (1)		34,000				53			—			34,053
	Corporate debt securities:
	Investment grade (1)		116,236				—			(1,054		)	115,182
	Non-investment grade (1)		17,881				—			(3,200		)	14,681
	Other securities		41,589				243			(716		)	41,116
	Total investment securities available-for-sale		$	2,619,205			$	21,128		$	(13,968	)	$	2,626,365
	As of December 31, 2013
	Investment securities available-for-sale:
	U.S. Treasury securities		$	495,053			$	201		$	(3,622	)	$	491,632
	U.S. government agency and U.S. government sponsored enterprise debt securities		406,807				242			(12,726		)	394,323
	U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities:
	Commercial mortgage-backed securities		182,257				1,062			(4,449		)	178,870
	Residential mortgage-backed securities		892,435				7,729			(14,927		)	885,237
	Municipal securities		297,390				1,122			(17,533		)	280,979
	Other residential mortgage-backed securities:
	Investment grade (1)		48,129				—			(1,802		)	46,327
	Other commercial mortgage-backed securities:
	Investment grade (1)		51,000				617			—			51,617
	Corporate debt securities:
	Investment grade (1)		312,726				613			(3,344		)	309,995
	Non-investment grade (1)		20,668				62			(5,629		)	15,101
	Other securities		80,025				555			(864		)	79,716
	Total investment securities available-for-sale		$	2,786,490			$	12,203		$	(64,896	)	$	2,733,797
	-1	Investment securities rated BBB- or higher by S&P, or Baa3 or higher by Moody are considered investment grade.  Conversely, investment securities rated below BBB- by S&P, or below Baa3 by Moody are considered non-investment grade.
	Realized Gains and Losses
	The following table presents the proceeds, gross realized gains, and gross realized losses related to the sales of investment securities for the years ended December 31, 2014, 2013, and 2012:
			2014				2013			2012
							(In thousands)
	Proceeds from sales		$	623,689			$	663,569		$	1,230,134
	Gross realized gains		$	10,978			$	13,904		$	28,211
	Gross realized losses		$	127		$(1)	$	1,815		$	27,454
	Related tax expense		$	4,557			$	5,077		$	318
	-1	The gross $127 thousand of losses resulted from the investment securities acquired from MetroCorp which were sold immediately after the acquisition closed.
	Declines in the fair value of securities below their cost that are deemed to be an OTTI are recognized in earnings to the extent the impairment is related to credit losses. The following table presents a rollforward of the amounts related to the OTTI credit losses recognized in earnings for the years ended December 31, 2014, 2013, and 2012:
			2014				2013			2012
			(In thousands)
	Beginning balance		$	115,511			$	115,511		$	115,412
	Addition of OTTI that was not previously recognized		—				—			—
	Additional increases to the amount related to the credit loss for which an OTTI was previously recognized		—				—			99
	Reduction for securities sold		(3,173		)		—			—
	Ending balance		$	112,338			$	115,511		$	115,511
	The Company believes that it is not more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis. No OTTI credit losses were recognized for the years ended December 31, 2014 and 2013. For the year ended December 31, 2012, the Company recorded $5.2 million of OTTI on a pre-tax basis, of which $99 thousand was credit-related impairment losses that was recorded through earnings, and $5.1 million was non-credit related impairment losses that was recorded through other comprehensive income for the pooled trust preferred securities which was due to credit downgrades caused by increases in market spreads, concerns regarding the housing market and lack of liquidity in the market. For the year ended December 31, 2014, the Company realized a gain of $802 thousand from the sale of a non-investment grade corporate debt security with previously recognized OTTI credit losses of $3.2 million.
	Unrealized Losses
	The following tables present the Company’s investment portfolio’s gross unrealized losses and related fair values, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, as of December 31, 2014 and 2013:
			Less Than 12 Months							12 Months or More						Total
			Fair				Unrealized			Fair			Unrealized			Fair		Unrealized
			Value				Losses			Value			Losses			Value		Losses
		(In thousands)
As of December 31, 2014
Investment securities available-for-sale:
U.S. Treasury securities		$	170,260			$	(266	)	$	163,800		$	(1,371	)	$	334,060	$	(1,637	)
U.S. government agency and U.S. government sponsored enterprise debt securities		69,438				(504		)	124,104			(889		)	193,542		(1,393		)
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities:
Commercial mortgage-backed securities		45,405				(257		)	16,169			(336		)	61,574		(593		)
Residential mortgage-backed securities		81,927				(270		)	241,047			(3,808		)	322,974		(4,078		)
Municipal securities		6,391				(26		)	61,107			(1,136		)	67,498		(1,162		)
Other residential mortgage-backed securities:
Investment grade		—				—			7,217			(135		)	7,217		(135		)
Corporate debt securities:
Investment grade		25,084				(12		)	90,098			(1,042		)	115,182		(1,054		)
Non-investment grade		—				—			14,681			(3,200		)	14,681		(3,200		)
Other securities		15,885				(716		)	—			—			15,885		(716		)
Total investment securities available-for-sale		$	414,390			$	(2,051	)	$	718,223		$	(11,917	)	$	1,132,613	$	(13,968	)
		Less Than 12 Months							12 Months or More						Total
		Fair				Unrealized			Fair			Unrealized			Fair		Unrealized
		Value				Losses			Value			Losses			Value		Losses
		(In thousands)
As of December 31, 2013
Investment securities available-for-sale:
U.S. Treasury securities		$	337,248			$	(3,622	)	$	—		$	—		$	337,248	$	(3,622	)
U.S. government agency and U.S. government sponsored enterprise debt securities		387,097				(12,726		)	—			—			387,097		(12,726		)
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities:
Commercial mortgage-backed securities		114,754				(3,280		)	16,065			(1,169		)	130,819		(4,449		)
Residential mortgage-backed securities		502,285				(10,570		)	92,540			(4,357		)	594,825		(14,927		)
Municipal securities		173,782				(10,765		)	47,892			(6,768		)	221,674		(17,533		)
Other residential mortgage-backed securities:
Investment grade		46,327				(1,802		)	—			—			46,327		(1,802		)
Corporate debt securities:
Investment grade		193,482				(1,538		)	79,442			(1,806		)	272,924		(3,344		)
Non-investment grade		—				—			14,422			(5,629		)	14,422		(5,629		)
Other securities		48,098				(864		)	—			—			48,098		(864		)
Total investment securities available-for-sale		$	1,803,073			$	(45,167	)	$	250,361		$	(19,729	)	$	2,053,434	$	(64,896	)
At each reporting date, the Company examines all individual securities that are in an unrealized loss position for OTTI.  Specific investment related factors, such as the nature of the investments, the severity and duration of the loss, the probability of collecting all amounts due, the analysis of the issuers of the securities and whether there has been any cause for default on the securities and any change in the rating of the securities by various rating agencies, are examined to assess impairment. Additionally, the Company evaluates whether the creditworthiness of the issuer calls the realization of contractual cash flows into question. The Company takes into consideration the financial resources, intent and its overall ability to hold the securities and not be required to sell them until their fair values recover.
The majority of the total unrealized losses related to securities are related to residential agency mortgage-backed securities, non-investment grade corporate debt securities and U.S. Treasury securities. As of December 31, 2014, residential agency mortgage-backed securities, non-investment grade corporate debt securities and U.S. Treasury securities represented 30%, 1% and 33%, respectively, of the total investment securities available-for-sale portfolio. As of December 31, 2013, residential agency mortgage-backed securities, non-investment grade corporate debt securities and U.S. Treasury securities represented 32%, 1% and 18%, respectively, of the total investment securities available-for-sale portfolio. The unrealized losses on these securities are primarily attributed to yield curve movement, together with the widened liquidity spread and credit spread. The issuers of these securities have not, to the Company's knowledge, established any cause for default on these securities. These securities have fluctuated in value since their purchase dates as market interest rates have fluctuated.
Management believes the impairments relating to the years ended December 31, 2014 and 2013 detailed in the tables of gross unrealized losses above are temporary and are not impaired due to reasons of credit quality. Accordingly, no impairment loss has been recorded in the Company’s consolidated statements of income for the years ended December 31, 2014 and 2013.
Investment Securities Maturities
The following table presents the scheduled maturities of investment securities as of December 31, 2014:
		Amortized				Estimated
		Cost				Fair Value
		(In thousands)
Due within one year		$	343,193			$	339,814
Due after one year through five years		1,018,469				1,022,566
Due after five years through ten years		328,317				329,172
Due after ten years		929,226				934,813
Total investment securities available-for-sale		$	2,619,205			$	2,626,365
Actual maturities of mortgage-backed securities can differ from contractual maturities because borrowers have the right to prepay obligations. In addition, such factors as prepayments and interest rates may affect the yields on the carrying values of mortgage-backed securities.
As of December 31, 2014 and 2013, investment securities available-for-sale with a par value of $1.93 billion and $1.97 billion, respectively, were pledged to secure public deposits, FHLB advances, repurchase agreements, the Federal Reserve Bank’s discount window, or for other purposes required or permitted by law.

DERIVATIVES

DERIVATIVES	12 Months Ended
	Dec. 31, 2014
DERIVATIVES
DERIVATIVES	NOTE 7 — DERIVATIVES
	The following table presents the total notional and fair values of the Company’s derivatives as of December 31, 2014 and 2013.
			31-Dec-14												31-Dec-13
			Notional				Fair Value								Notional				Fair Value
			Amount				Derivative				Derivative				Amount				Derivative				Derivative
							Assets (1)				Liabilities (1)								Assets (1)				Liabilities (1)
			(In thousands)
	Derivatives designated as hedging instruments:
	Interest rate swaps on certificates of deposits		$	132,667			$	—			$	9,922			$	135,000			$	—			$	16,906
	Total derivatives designated as hedging instruments		$	132,667			$	—			$	9,922			$	135,000			$	—			$	16,906
	Derivatives not designated as hedging instruments:
	Foreign exchange options		$	85,614			$	6,136			$	—			$	85,614			$	6,290			$	—
	Embedded derivative liabilities		47,838				—				3,392				51,505				—				3,655
	Interest rate swaps and caps		4,858,391				41,534				41,779				3,834,072				28,078				26,352
	Foreign exchange contracts		680,629				8,123				9,171				635,428				6,181				3,349
	Total derivatives not designated as hedging instruments		$	5,672,472			$	55,793			$	54,342			$	4,606,619			$	40,549			$	33,356
	(1) Derivative assets are included in other assets. Derivative liabilities are included in other liabilities and deposits.
	Derivatives Designated as Hedging Instruments
	Interest Rate Swaps on Certificates of Deposits — The Company is exposed to changes in the fair value of certain fixed rate certificates of deposits due to changes in the benchmark interest rate, London Interbank Offering Rate (“LIBOR”). Interest rate swaps designated as fair value hedges involve the receipt of fixed rate amounts from a counterparty in exchange for the Company making variable-rate payments over the life of the agreements without the exchange of the underlying notional amount. The interest rate swaps and the related certificates of deposits have the same maturity dates.
	In 2014, the Company undesignated one of its existing hedged relationships and simultaneously redesignated into a new hedging relationship in order to realign the hedged notional of its interest rate swap against the outstanding notional balance of the related certificate of deposit, as a result of cumulative death puts on the certificate of deposit. As of December 31, 2014 and 2013, the total notional amounts of the interest rate swaps on certificates of deposits were $132.7 million and $135.0 million, respectively. The fair value liabilities of the interest rate swaps were $9.9 million and $16.9 million as of December 31, 2014 and 2013, respectively.
	The following table presents the net gains (losses) recognized in the consolidated statements of income for the years ended December 31, 2014, 2013 and 2012:
		Years ended December 31,
		2014				2013				2012
		(In thousands)
	Gains (losses) recorded in interest expense:
	Recognized on interest rate swaps	$	6,885			$	(9,255	)		$	(1,076	)
	Recognized on certificates of deposits	(6,784		)		9,675				4,686
	Net amount recognized on fair value hedges (ineffective portion)	$	101			$	420			$	3,610
	Net interest expense recognized on interest rate swaps	$	(6,703	)		$	(3,153	)		$	(3,793	)
	Derivatives Not Designated as Hedging Instruments
	Foreign Exchange Options — During 2010, the Company entered into foreign exchange option contracts with major brokerage firms to economically hedge against foreign exchange fluctuations in certain certificates of deposits available to its customers. These certificates of deposits have a term of 5 years and pay interest based on the performance of the RMB relative to the USD. Under ASC 815, a certificate of deposit that pays interest based on changes in foreign exchange rates is a hybrid instrument with an embedded derivative that must be accounted for separately from the host contract (i.e., the certificate of deposit). In accordance with ASC 815, both the embedded derivative instruments and the freestanding foreign exchange option contracts are recorded at fair value.
	As of December 31, 2014 and 2013, the notional amounts of the foreign exchange options were $85.6 million. As of December 31, 2014 and 2013, the notional amounts of the embedded derivative liabilities were $47.8 million and $51.5 million, respectively.  The fair values of the foreign exchange options and the embedded derivative liabilities amounted to a $6.1 million asset and a $3.4 million liability, respectively, as of December 31, 2014. The fair values of the foreign exchange options and embedded derivative liabilities amounted to a $6.3 million asset and a $3.7 million liability, respectively, as of December 31, 2013.
	Interest Rate Swaps and Caps — The Company enters into interest rate derivatives including interest rate swaps and caps with its customers to allow them to hedge against the risk of rising interest rates on their variable rate loans. To economically hedge against the interest rate risks in the products offered to its customers, the Company enters into mirror interest rate contracts with institutional counterparties.  As of December 31, 2014, the total notional amounts of interest rate swaps and caps, including mirror transactions with institutional counterparties and the Company’s customers totaled to $2.45 billion for derivatives that were in an asset valuation position and $2.40 billion for derivatives that were in a liability valuation position. As of December 31, 2013, the total notional amounts of interest rate swaps and caps, including mirror transactions with institutional counterparties and the Company’s customers totaled to $1.92 billion for derivatives that were in an asset valuation position and $1.91 billion for derivatives that were in a liability valuation position.
	The fair values of interest rate swap and cap contracts with institutional counterparties and the Company’s customers amounted to a $41.5 million asset and a $41.8 million liability as of December 31, 2014. The fair values of interest rate swap and cap contracts with institutional counterparties and the Company’s customers amounted to a $28.1 million asset and a $26.4 million liability as of December 31, 2013.
	Foreign Exchange Contracts — The Company enters into short-term foreign exchange forward contracts on a regular basis to economically hedge against foreign exchange rate fluctuations. As of December 31, 2014 and 2013, the notional amounts of short-term foreign exchange contracts were $680.6 million and $607.9 million, respectively.  The fair values of the short-term foreign exchange contracts recorded were an $8.1 million asset and a $9.2 million liability as of December 31, 2014. The fair values of short-term foreign exchange contracts recorded were a $6.2 million asset and a $3.3 million liability as of December 31, 2013.
	The Company also enters into long-term foreign exchange contracts to purchase/sell foreign currencies at set rates in the future. There was no long-term foreign exchange contract outstanding as of December 31, 2014. As of December 31, 2013, the notional amounts of long-term foreign exchange contracts totaled $27.5 million. The fair values of long-term foreign exchange contracts amounted to a $200 thousand asset and a $183 thousand liability as of December 31, 2013.
	Equity Swap Agreements — In December 2007, the Company entered into two equity swap agreements with a major investment brokerage firm to economically hedge against market fluctuations in a promotional equity index certificate of deposit product offered to bank customers which has a term of 5 years and pays interest based on the performance of the Hang Seng China Enterprise Index. Under ASC 815, a certificate of deposit that pays interest based on changes in an equity index is a hybrid instrument with an embedded derivative (i.e. equity call option) that must be accounted for separately from the host contract (i.e. the certificate of deposit). In accordance with ASC 815, both the embedded equity call options on the certificates of deposit and the freestanding equity swap agreements are marked-to-market each reporting period with resulting changes in fair value recorded in the consolidated statements of income. These equity swap agreements matured during 2012.
	The following table presents the net (losses) gains recognized in the Company’s consolidated statements of income related to derivatives not designated as hedging instruments.
			Location in		Year Ended December 31,
			Consolidated
			Statements of Income		2014				2013				2012
					(In thousands)
	Derivatives not designated as hedging instruments:
	Equity swap agreements		Other operating income		$	—			$	—			$	2
	Foreign exchange options		Foreign exchange income		103				653				389
	Foreign exchange options with embedded derivatives		Other operating expense		5				23				101
	Interest rate swaps and caps		Other operating income		(1,865		)		1,582				592
	Foreign exchange contracts		Foreign exchange income		(3,880		)		2,624				(228		)
			Total net (losses)		$	(5,637	)		$	4,882			$	856
	Credit-Risk-Related Contingent Features — Certain OTC derivative contracts of the Company contain early termination provisions that may require the Company to settle any outstanding balances upon the occurrence of a specified credit-risk-related event. These events, which are defined by the existing derivative contracts, primarily relate to downgrades in the credit ratings of East West Bank to below investment grade. In the event that East West Bank’s credit rating had been downgraded to below investment grade, no additional collateral would have been required to be posted since the liabilities related to such contracts were fully collateralized as of December 31, 2014 and 2013.
	Balance Sheet Offsetting
	Derivatives — The Company has entered into agreements with counterparty financial institutions, which include master netting agreements.  However, the Company has elected to account for all derivatives with counterparty institutions on a gross basis. The following tables present gross derivatives in the consolidated balance sheets and the respective collateral received or pledged in the form of other financial instruments, which are generally marketable securities and/or cash. The collateral amounts in these tables are limited to the outstanding balances of the related asset or liability (after netting is applied); thus instances of overcollateralization are not shown.
			As of December 31, 2014
			(In thousands)
			Gross Amounts				Gross Amounts				Net Amounts of				Gross Amounts Not Offset on the
			of Recognized				Offset on the				Assets Presented				Consolidated Balance Sheets
			Assets				Consolidated				on the
							Balance Sheet				Consolidated
	Assets										Balance Sheet				Financial					Collateral					Net Amount
															Instruments					Received
	Derivatives		$	12,396			$	—			$	12,396			$	(5,725	)	(1)		$	(3,463	)	(2)		$	3,208
			Gross Amounts				Gross Amounts				Net Amounts of				Gross Amounts Not Offset on the
			of Recognized				Offset on the				Liabilities				Consolidated Balance Sheets
			Liabilities				Consolidated				Presented on the
			Balance Sheet				Consolidated
Liabilities										Balance Sheet				Financial					Collateral					Net Amount
														Instruments					Posted
Derivatives		$	56,505			$	—			$	56,505			$	(5,725	)	(1)		$	(49,951	)	(3)		$	829
		As of December 31, 2013
		(In thousands)
		Gross Amounts				Gross Amounts				Net Amounts of				Gross Amounts Not Offset on the
		of Recognized				Offset on the				Assets Presented				Consolidated Balance Sheets
		Assets				Consolidated				on the
						Balance Sheet				Consolidated
Assets										Balance Sheet				Financial					Collateral					Net Amount
														Instruments					Received
Derivatives		$	16,043			$	—			$	16,043			$	(11,363	)	(1)		$	(4,680	)	(2)		$	—
		Gross Amounts				Gross Amounts				Net Amounts of				Gross Amounts Not Offset on the
		of Recognized				Offset on the				Liabilities				Consolidated Balance Sheets
		Liabilities				Consolidated				Presented on the
						Balance Sheet				Consolidated
Liabilities										Balance Sheet				Financial					Collateral					Net Amount
														Instruments					Posted
Derivatives		$	33,849			$	—			$	33,849			$	(11,363	)	(1)		$	(22,486	)	(3)		$	—
-1	Represents the netting of derivative receivable and payable balance for the same counterparty under enforceable master netting arrangements if the Company has elected to net.
-2	Represents cash and securities received against derivative assets with the same counterparty that are subject to enforceable master netting arrangements. Includes approximately $3.5 million of cash collateral received as of December 31, 2014.
-3	Represents cash and securities pledged against derivative liabilities with the same counterparty that are subject to enforceable master netting arrangements. Includes approximately $12.8 million and $187 thousand of cash collateral posted as of December 31, 2014 and December 31, 2013, respectively.
Refer to Note 1 for the Company’s accounting policy on derivatives and Note 3 for fair value measurement disclosures on derivatives.

COVERED_ASSETS_AND_FDIC_INDEMN

COVERED ASSETS AND FDIC INDEMNIFICATION ASSET	12 Months Ended
	Dec. 31, 2014
COVERED ASSETS AND FDIC INDEMNIFICATION ASSET
COVERED ASSETS AND FDIC INDEMNIFICATION ASSET	NOTE 8 — COVERED ASSETS AND FDIC INDEMNIFICATION ASSET
	Covered Assets
	Covered assets consist of loans receivable and OREO that were acquired in the WFIB acquisition on June 11, 2010 and in the UCB acquisition on November 6, 2009 for which the Company entered into shared-loss agreements with the FDIC. The shared-loss agreements covered over 99% of the loans originated by WFIB and all of the loans originated by UCB, excluding the loans originated by UCB in China under its United Commercial Bank China (Limited) subsidiary. The Company shares in the losses, which began with the first dollar of loss incurred, on covered assets under the shared-loss agreements.
	Pursuant to the terms of the shared-loss agreements, the FDIC is obligated to reimburse the Company 80% of eligible losses for both UCB and WFIB with respect to covered assets. For the UCB covered assets, the FDIC will reimburse the Company for 95% of eligible losses in excess of $2.05 billion. The Company has a corresponding obligation to reimburse the FDIC for 80% or 95%, as applicable, of eligible recoveries with respect to covered assets. The commercial loan and single-family residential mortgage loan shared-loss provisions are in effect for 5 years and 10 years, respectively, from the acquisition date and the loss recovery provisions are in effect for 8 years and 10 years, respectively, from the acquisition date.
	The shared-loss coverage for the commercial loans acquired from the UCB and WFIB acquisitions end on the fifth anniversary of the shared-loss agreements with the FDIC. Accordingly, the shared-loss coverage of the UCB and WFIB commercial loans and other assets shared-loss agreements was extended to December 31, 2014 and will extend through June 30, 2015, respectively. Covered loans, net of discount was $1.48 billion as of December 31, 2014. The balance of the UCB commercial loans and other assets, net of discount was $1.10 billion as of December 31, 2014. The loss recovery provisions of the UCB and WFIB commercial loans’ shared-loss agreements will extend for an additional three years, through December 31, 2017 and June 30, 2018, respectively. Additionally, both the shared-loss coverage and loss recovery provisions of the UCB and WFIB residential loan shared-loss agreements are in effect for a 10-year period, extending through November 30, 2019 and June 30, 2020, respectively. Upon expiration of the shared-loss coverage periods, any losses on loans will no longer be shared with the FDIC.
	Forty-five days following the 10th anniversary of the respective acquisition date, the Company will be required to pay to the FDIC a calculated amount, based on the specific thresholds of losses not being reached. The calculation of this potential liability as stated in the shared-loss agreements is 50% of the excess, if any of (i) 20% of the Intrinsic Loss Estimate less (ii) the sum of (a) 25% of the asset discount plus (b) 25% of the Cumulative Shared-Loss Payments plus (c) the Cumulative Servicing Amount, if net losses on covered assets subject to the stated threshold are not reached. The Company recorded a liability related to both UCB and WFIB shared-loss agreements of $110.3 million and $74.7 million, respectively, as of December 31, 2014 and December 31, 2013.
	The Company’s covered loan portfolio consists of (1) PCI loans and (2) covered advances drawn down on existing commitment lines, subsequent to the UCB and WFIB acquisition dates (“covered advances”).  PCI covered loans represent acquired loans, which the Company elected to account for in accordance with ASC 310-30.  As of the respective acquisition dates, the UCB and WFIB loan portfolios included unfunded commitments for commercial lines of credit, construction draws and other lending activities. These commitments are covered under the shared-loss agreements.  However, the covered advances are not accounted for under ASC 310-30.
	At acquisition, loans were pooled and accounted for at fair value, which represents the discounted value of the expected cash flows of the loan portfolio. Nonaccretable difference represents the Company’s estimate of the expected credit losses, which was considered in determining the fair value of the loans as of the respective acquisition dates. In estimating nonaccretable difference, the Company (a) calculated the contractual amount and timing of undiscounted principal and interest payments (the “undiscounted contractual cash flows”) and (b) estimated the amount and timing of undiscounted expected principal and interest payments (the “undiscounted expected cash flows”).  In the determination of contractual cash flows and cash flows expected to be collected, the Company assumed no prepayments on the PCI nonaccrual loan pools since the Company does not anticipate any significant prepayments on credit impaired loans. For the PCI accrual loans for single-family, multifamily and CRE, the Company utilized a recognized third party vendor to obtain prepayment speeds. As the prepayment rates for the construction, land, and commercial and consumer loan pools have historically been low, the Company applied the prepayment assumptions of the current portfolio using internal modeling. The difference between the undiscounted contractual cash flows and the undiscounted expected cash flows is the nonaccretable difference. The amount by which the undiscounted expected cash flows exceed the estimated fair value (the “accretable yield”) is accreted into interest income over the life of the loans.
	The following table presents the composition of the covered loans as of December 31, 2014 and 2013:
			Year Ended December 31,
			2014					2013
			(In thousands)
	CRE		$	705,665				$	1,103,530
	Construction and land		46,054					163,833
	Total CRE		751,719					1,267,363
	C&I		252,986					426,621
	Residential single-family		240,650					290,095
	Residential multifamily		296,599					403,508
	Total residential		537,249					693,603
	Other consumer		62,986					73,973
	Total covered loans		1,604,940			(1)		2,461,560			(2)
	Covered discount		(127,246		)			(265,917		)
	Net valuation of loans		1,477,694					2,195,643
	Allowance for loan losses on covered loans		(3,505		)			(7,745		)
	Total covered loans, net		$	1,474,189				$	2,187,898
	Collectively evaluated for impairment		$	253,312		(1)		$	320,185		(2)
	Acquired with deteriorated credit quality		1,224,382					1,875,458
	Total		$	1,477,694				$	2,195,643
	-1	Includes $253.3 million of covered advances comprised of $154.8 million, $59.4 million, $27.3 million and $11.8 million of C&I, CRE, consumer and residential loans, respectively.
	-2	Includes $320.2 million of covered advances comprised of $230.6 million, $46.7 million, $30.9 million and $12.0 million of C&I, CRE, consumer and residential loans, respectively.
	Credit Quality Indicators
	Covered loans acquired are subject to the Company’s internal and external credit review and monitoring. The same credit quality indicators are reviewed for the covered portfolio as the non-covered portfolio, to enable the monitoring of the borrower’s credit and the likelihood of repayment.
	Loans are risk rated based on analysis of the current state of the borrower’s credit quality. The analysis of credit quality includes a review of all repayment sources, the borrower’s current financial and liquidity status and all other relevant information. The Company utilizes an eight grade risk rating system, where a higher grade represents a higher level of credit risk. The eight grade risk rating system can be generally classified by the following categories: Pass, Watch, Special Mention, Substandard, Doubtful and Loss. The risk ratings reflect the relative strength of the repayment sources. Refer to Note 9 for a full discussion of risk ratings.
	As of December 31, 2014 and December 31, 2013, the majority of the PCI covered loan portfolio was performing better than expected from the initial estimates on acquisition. As a result, the Company reduced the nonaccretable difference due to the improved performance of the portfolio.  By decreasing the nonaccretable difference, the overall accretable yield will increase, thus increasing the interest income recognized over the remaining life of the loans. This reduction was primarily due to the lower loss rate and loan paydowns.  However, the Company has experienced some credit deterioration in certain PCI covered loan pools. Based on the Company’s estimates of cash flows expected to be collected, the Company will establish an allowance for the PCI covered pool of loans, with a charge to income through the provision for loan losses, where appropriate.  As of December 31, 2014, the Company has established an allowance of $424 thousand on $61.6 million of PCI covered loans. As of December 31, 2013, an allowance of $2.3 million was established on $129.7 million of PCI covered loans. The allowance balances for both periods were allocated mainly to the PCI covered CRE loans. With respect to the covered advances, losses are estimated collectively for groups of loans with similar characteristics. Refer to Note 9 for a discussion on the Company’s allowance for loan losses methodology.
	The following tables present a summary of the activity in the allowance for loan losses on the PCI covered loans and the covered advances for the years ended December 31, 2014, 2013 and 2012:
			Year Ended December 31,
			2014												2013									2012
			Covered				PCI				Total				Covered			PCI		Total				Covered			PCI		Total
			Advances				Covered								Advances			Covered						Advances			Covered
							Loans											Loans									Loans
			(In thousands)
	Beginning balance		$	5,476			$	2,269			$	7,745			$	5,153		$	—	$	5,153			$	6,647		$	—	$	6,647
	Provision for (reversal of) loan losses		6,878				(1,845		)		5,033				1,759			2,269		4,028				5,016			—		5,016
	Charge-offs		(10,836		)		—				(10,836		)		(1,436		)	—		(1,436		)		(6,510		)	—		(6,510		)
	Recoveries		1,563				—				1,563				—			—		—				—			—		—
	Ending balance		$	3,081			$	424			$	3,505			$	5,476		$	2,269	$	7,745			$	5,153		$	—	$	5,153
	Ending balance allocated to:
	Collectively evaluated for impairment		$	3,081			$	—			$	3,081		(1)	$	5,476		$	—	$	5,476		(2)	$	5,153		$	—	$	5,153		(3)
	Acquired with deteriorated credit quality		—				424				424				—			2,269		2,269				—			—		—
	Ending balance		$	3,081			$	424			$	3,505			$	5,476		$	2,269	$	7,745			$	5,153		$	—	$	5,153
	-1	Allowance for loan losses of $2.0 million, $676 thousand, $223 thousand and $166 thousand are allocated to C&I, CRE, consumer and residential loans, respectively.
	-2	Allowance for loan losses of $3.2 million, $1.8 million, $341 thousand and $176 thousand are allocated to C&I, CRE, consumer and residential loans, respectively.
	-3	Allowance for loan losses of $2.4 million, $2.5 million and $194 thousand and $87 thousand are allocated to C&I, CRE, consumer and residential loans, respectively.
	The following tables present the credit risk rating categories for the covered loans by portfolio segments as of December 31, 2014 and 2013:
			Pass/Watch				Special				Substandard				Doubtful			Total
							Mention
			(In thousands)
	31-Dec-14
	CRE		$	579,133			$	12,575			$	113,957			$	—		$	705,665
	Construction and land		18,090				8,515				19,449				—			46,054
	Total CRE		597,223				21,090				133,406				—			751,719
	C&I		217,975				5,723				29,288				—			252,986
	Residential single-family		232,139				474				8,037				—			240,650
	Residential multifamily		247,893				—				48,706				—			296,599
Total residential		480,032				474				56,743				—			537,249
Other consumer		62,010				141				835				—			62,986
Total principal balance		$	1,357,240			$	27,428			$	220,272			$	—		$	1,604,940
		Pass/Watch				Special				Substandard				Doubtful			Total
						Mention
		(In thousands)
31-Dec-13
CRE		$	857,376			$	27,851			$	211,835			$	6,468		$	1,103,530
Construction and land		41,847				9,472				111,616				898			163,833
Total CRE		899,223				37,323				323,451				7,366			1,267,363
C&I		378,086				4,635				43,797				103			426,621
Residential single-family		281,246				733				8,116				—			290,095
Residential multifamily		373,024				785				29,699				—			403,508
Total residential		654,270				1,518				37,815				—			693,603
Other consumer		72,053				128				1,792				—			73,973
Total principal balance		$	2,003,632			$	43,604			$	406,855			$	7,469		$	2,461,560
Credit Risk and Concentration
At each respective acquisition date, the covered loans were grouped into pools of loans with similar characteristics and risk factors per ASC 310-30. The pools were first developed based on loan categories and performance status. As of December 31, 2014 and December 31, 2013, UCB covered loans comprised approximately 93% of total covered loans. In respect of the UCB acquisition, the loans were further segregated among the former UCB domestic, Hong Kong and China portfolios, representing three general geographic regions. The Company evaluated the make-up of geographic regions within the construction, land, and multi-family loan portfolios and further segregated these pools into distressed and non-distressed regions, based on the Company’s historical experience with real estate loans within the non-covered portfolio. As of the UCB acquisition date, 64%, 10% and 11% of the UCB portfolio were located in California, Hong Kong and New York, respectively. This assessment was factored into the initial estimates on acquisition and the discount applied to the loans. As such, geographic concentration risk is considered in the covered loan discount.
Covered Nonperforming Assets
The following table presents the Company’s covered nonperforming assets as of December 31, 2014 and December 31, 2013:
		December 31,
		2014				2013
		(In thousands)
Covered nonaccrual loans(1) (2) (3)		$	62,665			$	126,895
Other real estate owned covered, net		4,499				21,373
Total covered nonperforming assets		$	67,164			$	148,268
-1	Covered nonaccrual loans include loans that meet the criteria for nonaccrual but have a yield accreted through interest income under ASC 310-30.  All losses on covered loans are 80% reimbursed by the FDIC.
-2	Net of discount.
-3	Includes $10.1 million and $17.7 million of covered advances as of December 31, 2014 and December 31, 2013, respectively; and $52.6 million and $109.2 million of PCI loans as of December 31, 2014 and December 31, 2013, respectively.
As of December 31, 2014 and December 31, 2013, there were no accruing covered loans that were past due 90 days or more.
Troubled Debt Restructurings
The following table presents the Company’s troubled debt restructurings related to covered loans activity rollforward for the years ended December 31, 2014 and 2013:
						Year Ended December 31,
						2014				2013
						(In thousands)
Beginning balance						$	116,007			$	157,736
Additions						1,264				35,865
Transfers to covered OREO						(1,230		)		—
Charge-offs						(1,504		)		(10,167		)
Paydowns/Reductions						(71,810		)		(67,427		)
Ending Balance						$	42,727			$	116,007
Covered OREO
Covered OREO balances were $4.5 million and $21.4 million, net of valuation adjustments of $1.3 million and $2.4 million as of December 31, 2014 and December 31, 2013, respectively.  During the year ended December 31, 2014, 17 properties with an aggregate carrying value of $28.0 million were added through foreclosure. During the year ended December 31, 2014, the Company sold 29 covered OREO properties for total proceeds of $52.1 million resulting in a total net gain on sale of $8.5 million.
Accretable Yield
The following table presents the changes in the accretable yield for the PCI covered loans for the years ended December 31, 2014, 2013 and 2012:
		Year Ended December 31,
		2014				2013				2012
		(In thousands)
Beginning balance		$	461,545			$	556,986			$	785,165
Additions		—				—				—
Accretion		(214,209		)		(347,010		)		(382,132		)
Changes in expected cash flows		59,188				251,569				153,953
Ending balance		$	306,524			$	461,545			$	556,986
The excess cash flows expected to be collected over the initial fair value of the PCI loans is referred to as the accretable yield and is accreted into interest income using an effective yield method over the remaining life of the acquired loans. The accretable yield will change due to:
•	estimate of the remaining life of acquired loans which may change the amount of future interest income;
•	estimate of the amount of contractually required principal and interest payments over the estimated life that will not be collected (the nonaccretable difference); and
•	indices for acquired loans with variable rates of interest.
During the year ended December 31, 2014, the estimated amount of contractually required principal and interest payments over the estimated life that will not be collected (the nonaccretable difference) was reduced as the losses on certain loan pools were evaluated and determined to be lower than expected. As a result of the reduction in the nonaccretable yield, the accretable yield increased, as did the amortization of the FDIC indemnification asset. Consequently, $52.5 million and $190.3 million were reclassified from nonaccretable yield to accretable yield due to changes in loss rate assumptions for the years ended December 31, 2014 and 2013. Due to ongoing improvement in credit quality of the remaining covered loans, the accrued liability to the FDIC increased during 2014.
From December 31, 2013 to December 31, 2014, excluding scheduled principal payments, a total of $647.0 million of loans were removed from the covered loans accounted for under ASC 310-30 due to loans being paid in full, sold, transferred to covered OREO or charged-off. Interest income of $87.5 million related to payoffs and removals offset by charge-offs was recorded.
From December 31, 2012 to December 31, 2013, excluding scheduled principal payments, a total of $739.3 million of loans were removed from the covered loans accounted for under ASC 310-30 due to loans being paid in full, sold, transferred to covered OREO or charged-off. Interest income of $168.1 million related to payoffs and removals offset by charge-offs was recorded.
From December 31, 2011 to December 31, 2012, excluding scheduled principal payments, a total of $924.7 million of loans were removed from the covered loans accounted for under ASC 310-30 due to loans being paid in full, sold, transferred to covered OREO or charged-off. Interest income of $124.7 million related to payoffs and removals offset by charge-offs was recorded.
FDIC Indemnification Asset/Payable to FDIC, net
The Company is amortizing the difference between the recorded amount of the FDIC indemnification asset and the expected reimbursement from the FDIC over the life of the indemnification asset, in line with the improved accretable yield as discussed above.  As of December 31, 2014, due to continued payoffs and improved credit performance of the covered portfolio as compared to the Company's original estimates, the expected reimbursement from the FDIC under the shared-loss agreements has decreased and a payable to FDIC, net has been recorded.  In prior year, due to the estimated losses from the covered portfolio and the corresponding expected payments from the FDIC, the Company recorded an FDIC indemnification asset. As of December 31, 2014, the net liability to the FDIC was $96.1 million compared to a net asset of $74.7 million as of December 31, 2013.
The following table presents a summary of the FDIC indemnification asset/Payable to FDIC, net for the years ended December 31, 2014 and 2013:
		Year Ended December 31,
		2014				2013
		(In thousands)
Beginning balance		$	74,708			$	316,313
Amortization		(101,638		)		(99,055		)
Reductions (1)		(33,595		)		(95,536		)
Estimate of FDIC repayment (2)		(35,581		)		(47,014		)
Ending Balance		$	(96,106	)		$	74,708
-1	Reductions relate to charge-offs, partial prepayments, loan payoffs and loan sales which result in a corresponding reduction of the indemnification asset.
-2	This represents the change in the calculated estimate the Company will be required to pay the FDIC at the end of the FDIC shared-loss agreements, due to lower thresholds of losses.
FDIC Receivable
As of December 31, 2014, the FDIC shared-loss receivable was $1.0 million as compared to $30.3 million as of December 31, 2013. This receivable represents current reimbursable amounts from the FDIC, under the FDIC shared-loss agreements that have not yet been received. These reimbursable amounts include net charge-offs, loan related expenses and OREO-related expenses. Consequently, 100% of the loan related and OREO expenses are recorded as noninterest expense, 80% of reimbursable expense is recorded as noninterest income, netting to the 20% of actual expense paid by the Company. The FDIC also shares in 80% of recoveries received. Thus, the FDIC receivable is reduced when the Company receives payment from the FDIC as well as when recoveries occur. The FDIC shared-loss receivable is included in other assets on the consolidated balance sheet.
The following table presents a summary of the activity in the FDIC receivable for the years ended December 31, 2014 and 2013:
		Year Ended December 31,
		2014				2013
		(In thousands)
Beginning balance		$	30,261			$	73,091
Net (reduction) addition due to recovery or eligible expense/loss		(30,601		)		12,996
Payments to (received from) the FDIC		1,343				(55,826		)
Ending balance		$	1,003			$	30,261

NONCOVERED_LOANS_AND_ALLOWANCE

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES	12 Months Ended
	Dec. 31, 2014
NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES
NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES	NOTE 9 — NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES
	The following table presents the composition of non-covered loans receivable as of December 31, 2014 and December 31, 2013:
			31-Dec-14				31-Dec-13
			(In thousands)
	CRE:
	Income producing		$	5,611,485			$	4,301,030
	Construction		313,811				140,186
	Land		208,750				143,861
	Total CRE		6,134,046				4,585,077
	C&I:
	Commercial business		7,031,350				4,637,056
	Trade finance		806,744				723,137
	Total C&I		7,838,094				5,360,193
	Residential:
	Single-family		3,642,978				3,192,875
	Multifamily		1,177,690				992,434
	Total residential		4,820,668				4,185,309
	Consumer:
	Student loans		—				679,220
	Other consumer		1,456,643				868,518
	Total consumer		1,456,643				1,547,738
	Total non-covered loans (1)		20,249,451				15,678,317
	Unearned fees, premiums, and discounts, net		2,804				(23,672		)
	Allowance for loan losses on non-covered loans		(258,174		)		(241,930		)
	Non-covered loans, net		$	19,994,081			$	15,412,715
	-1	Loans net of ASC 310-30 discount.
	As of December 31, 2014 and December 31, 2013, covered and non-covered loans receivable totaling $14.66 billion and $10.57 billion, respectively, were pledged to secure borrowings from the FHLB and the Federal Reserve Bank.
	The Company’s CRE lending activities include loans to finance income-producing properties, construction and land loans.  The Company’s C&I lending activities include commercial business financing for small and middle-market businesses in a wide spectrum of industries.  Included in commercial business loans are loans for working capital, accounts receivable lines, inventory lines, Small Business Administration loans and lease financing.  The Company also offers a variety of international trade finance services and products, including letters of credit, revolving lines of credit, import loans, bankers’ acceptances, working capital lines, domestic purchase financing and pre-export financing.
	The Company’s residential single-family loans are primarily comprised of adjustable rate (“ARM”) first mortgage loans secured by one-to-four unit residential properties.  The Company’s ARM single-family loan programs generally have a one-year or three-year initial fixed period.  The Company’s residential multifamily loans are comprised mainly of variable rate loans that have a six-month or three-year initial fixed period. As of December 31, 2014, consumer loans were primarily comprised of HELOCs. As of December 31, 2013, consumer loans were primarily comprised of HELOCs and student loans.
	All of the loans that the Company originates are subject to its underwriting guidelines and loan origination standards. Management believes that the Company’s underwriting criteria and procedures adequately consider the unique risks which may come from these products. The Company conducts a variety of quality control procedures and periodic audits to ensure compliance with its origination standards, including criteria for lending and legal requirements.
	Credit Risk and Concentrations — The Company has a concentration of real estate loans in California.  As of December 31, 2014, the Company had $6.13 billion in non-covered CRE loans and $4.82 billion in non-covered residential loans, of which approximately 80% were secured by real properties located in California.  Deterioration in the real estate market generally, including residential and CRE, could result in additional loan charge-offs and provisions for loan losses in the future, which could have a material adverse effect on the Company’s financial condition, net income and capital. In addition, although most of the Company’s trade finance loans relate to trade with Asian countries, the majority of the Company’s loans are made to borrowers domiciled in the United States.  A substantial portion of this business involves California based customers engaged in import and export activities.
	Purchased Loans — During 2014, the Company purchased $113.2 million of loans, the majority of which were student loans guaranteed by the U.S. Department of Education. During 2013, the Company purchased $759.3 million loans, of which 63% of the purchased loans were comprised of student loans that were primarily guaranteed by the U.S. Department of Education. The remaining loans purchased during 2013 were comprised mainly of insurance premium financing loans which were included in the C&I and consumer loan portfolios.
	Acquired Loans — In January 2014, the Company acquired $1.19 billion of loans through its acquisition of MetroCorp, as discussed in Note 2 of the Company’s consolidated financial statements.  As of the acquisition date, approximately 6% of the acquired loans were credit impaired and accounted for in accordance with ASC 310-30. As of December 31, 2014, the balance of PCI loans acquired from the MetroCorp acquisition was $50.6 million.
	Loans Held for Sale — Loans held for sale were $46.0 million and $205.0 million as of December 31, 2014 and December 31, 2013, respectively. Loans held for sale are recorded at the lower of cost or fair value.  Fair value is derived from current market prices.  $837.4 million and $97.1 million of net loans receivable were reclassified from loans held for investment to loans held for sale during 2014 and 2013, respectively. Loans transferred were primarily comprised of student loans and C&I loans in 2014 and in 2013. These loans were purchased by the Company with the original intent to be held for investment. However, subsequent to the purchase, the Company’s intent for these loans changed and they were consequently reclassified to loans held for sale. $5.2 million of write-downs related to loans transferred from loans held for investment to loans held for sale were recorded to allowance for loan losses for the year ended December 31, 2014. The Company did not record any write-downs related to loans transferred from loans held for investment to loans held for sale for the year ended December 31, 2013.
	Proceeds from total loans sold were $1.14 billion, resulting in net gains of $39.1 million during 2014. The majority of loans sold in 2014 were comprised of student loans and commercial loans. In comparison, proceeds from total loans sold were $376.4 million and $428.7 million in 2013 and 2012, respectively, resulting in net gains of $7.8 million and $17.0 million during 2013 and 2012, respectively.  Loans sold in 2013 and 2012 primarily comprised of student loans and commercial loans, respectively.
	Credit Quality Indicators — Loans are risk rated based on analysis of the current state of the borrower’s credit quality. The analysis of credit quality includes a review of all repayment sources, the borrower’s current payment performance/delinquency, current financial and liquidity status and all other relevant information.  For single-family residential loans, payment performance/delinquency is the driving indicator for the risk ratings.  However, the risk ratings remain the overall credit quality indicator for the Company as well as the credit quality indicator utilized for estimating the appropriate allowance for loan losses. The Company utilizes an eight grade risk rating system, where a higher grade represents a higher level of credit risk. The eight grade risk rating system can be generally classified by the following categories: Pass, Watch, Special Mention, Substandard, Doubtful and Loss. The risk ratings reflect the relative strength of the repayment sources.
	Pass and Watch loans are generally considered to have sufficient sources of repayment in order to repay the loan in full in accordance with all terms and conditions. These borrowers may have some credit risk that requires monitoring, but full repayment is expected. Special Mention loans are considered to have potential weaknesses that warrant closer attention by management. Special Mention is considered a transitory grade. If any potential weaknesses are resolved, the loan is upgraded to a Pass or Watch grade. If negative trends in the borrower’s financial status or other information indicates that the repayment sources may become inadequate, the loan is downgraded to a Substandard grade. Substandard loans are considered to have well-defined weaknesses that jeopardize the full and timely repayment of the loan. Substandard loans have a distinct possibility of loss if the deficiencies are not corrected. Additionally, when management has assessed a potential for loss but a distinct possibility of loss is not recognizable, the loan is still classified as Substandard. Doubtful loans have insufficient sources of repayment and a high probability of loss. Loss loans are considered to be uncollectible and of such little value that they are no longer considered bankable assets. These internal risk ratings are reviewed routinely and adjusted due to changes in the borrowers' status and likelihood of loan repayment.
	The following tables present the credit risk rating categories for non-covered loans by portfolio segment as of December 31, 2014 and 2013:
			Pass/Watch				Special				Substandard				Doubtful				Loss				Total
							Mention
			(In thousands)
	31-Dec-14
	CRE:
	Income producing		$	5,244,022			$	54,431			$	313,032			$	—			$	—			$	5,611,485
	Construction		306,923				—				6,888				—				—				313,811
	Land		179,319				5,701				23,730				—				—				208,750
	C&I:
	Commercial business		6,783,051				128,578				119,133				533				55				7,031,350
	Trade finance		766,575				10,193				29,976				—				—				806,744
	Residential:
	Single-family		3,624,097				3,143				15,738				—				—				3,642,978
	Multifamily		1,096,572				5,124				75,994				—				—				1,177,690
	Consumer:
	Student loans		—				—				—				—				—				—
	Other consumer		1,452,953				1,005				2,685				—				—				1,456,643
	Total		$	19,453,512			$	208,175			$	587,176			$	533			$	55			$	20,249,451
			Pass/Watch				Special				Substandard				Doubtful				Loss				Total
							Mention
			(In thousands)
	31-Dec-13
	CRE:
	Income producing		$	4,032,269			$	56,752			$	212,009			$	—			$	—			$	4,301,030
	Construction		127,138				6,160				6,888				—				—				140,186
	Land		116,000				9,304				18,557				—				—				143,861
C&I:
Commercial business		4,400,847				92,315				143,894				—				—				4,637,056
Trade finance		681,345				22,099				19,693				—				—				723,137
Residential:
Single-family		3,167,337				8,331				17,207				—				—				3,192,875
Multifamily		923,697				1,634				67,103				—				—				992,434
Consumer:
Student loans		677,094				445				1,681				—				—				679,220
Other consumer		865,752				244				2,522				—				—				868,518
Total		$	14,991,479			$	197,284			$	489,554			$	—			$	—			$	15,678,317
Nonaccrual and Past Due Loans
The following tables below present an aging analysis of the Company’s non-covered loans and loans held for sale, segregated by portfolio segment, as of December 31, 2014 and 2013:
		Accruing				Accruing				Total				Nonaccrual				Nonaccrual				Total				Current				Total
		Loans				Loans				Accruing				Loans Less				Loans				Nonaccrual				Accruing
		30-59 Days				60-89 Days				Past Due				Than 90 Days				90 or More				Loans				Loans
		Past Due				Past Due				Loans				Past Due				Days Past Due
		(In thousands)
31-Dec-14
CRE:
Income producing		$	14,171			$	3,593			$	17,764			$	29,576			$	9,109			$	38,685			$	5,555,036			$	5,611,485
Construction		—				—				—				—				6,888				6,888				306,923				313,811
Land		—				—				—				254				2,502				2,756				205,994				208,750
C&I:
Commercial business		3,073				2,884				5,957				5,514				14,689				20,203				7,005,190				7,031,350
Trade finance		—				—				—				73				—				73				806,671				806,744
Residential:
Single-family		6,375				1,294				7,669				2,894				4,936				7,830				3,627,479				3,642,978
Multifamily		4,350				507				4,857				12,460				8,336				20,796				1,152,037				1,177,690
Consumer:
Student loans		—				—				—				—				—				—				—				—
Other consumer		2,154				162				2,316				115				540				655				1,453,672				1,456,643
Loans held for sale		642				175				817				—				3,157				3,157				41,976				45,950
Total (1)		$	30,765			$	8,615			$	39,380			$	50,886			$	50,157			$	101,043			$	20,154,978			$	20,295,401
Unearned fees, premiums and discounts, net																														2,804
Total recorded investment in non-covered loans and loans held for sale																														$	20,298,205
-1	Loans net of ASC 310-30 discount.
		Accruing				Accruing				Total				Nonaccrual				Nonaccrual				Total				Current				Total
		Loans				Loans				Accruing				Loans Less				Loans				Nonaccrual				Accruing
		30-59 Days				60-89 Days				Past Due				Than 90 Days				90 or More				Loans				Loans
		Past Due				Past Due				Loans				Past Due				Days Past Due
		(In thousands)
31-Dec-13
CRE:
Income producing		$	12,746			$	1,798			$	14,544			$	13,924			$	22,549			$	36,473			$	4,250,013			$	4,301,030
Construction		—				—				—				—				6,888				6,888				133,298				140,186
Land		—				—				—				265				3,223				3,488				140,373				143,861
C&I:
Commercial business		3,428				6,259				9,687				6,437				15,486				21,923				4,605,446				4,637,056
Trade finance		—				—				—				—				909				909				722,228				723,137
Residential:
Single-family		4,694				922				5,616				—				11,218				11,218				3,176,041				3,192,875
Multifamily		8,580				531				9,111				19,661				7,972				27,633				955,690				992,434
Consumer:
Student loans		541				445				986				—				1,681				1,681				676,553				679,220
Other consumer		293				1				294				175				1,263				1,438				866,786				868,518
Loans held for sale		—				—				—				—				—				—				204,970				204,970
Total		$	30,282			$	9,956			$	40,238			$	40,462			$	71,189			$	111,651			$	15,731,398			$	15,883,287
Unearned fees, premiums and discounts, net																														(23,672		)
Total recorded investment in non-covered loans and loans held for sale																														$	15,859,615
Loans 90 or more days past due are generally placed on nonaccrual status, at which point interest accrual is discontinued and all unpaid accrued interest is reversed against interest income. Additionally, loans that are not 90 or more days past due but have identified deficiencies, including delinquent TDRs, are also placed on nonaccrual status.
Troubled Debt Restructurings
A TDR is a modification of the terms of a loan when the lender, for economic or legal reasons related to the borrower’s financial difficulties, grants a concession to the borrower. The concessions may be granted in various forms, including a below-market change in the stated interest rate, reduction in the loan balance or accrued interest, extension of the maturity date with a stated interest rate lower than the current market rate or note splits referred to as A/B notes. In A/B note restructurings, the original note is bifurcated into two notes where the A note represents the portion of the original loan which allows for acceptable loan-to-value and debt coverage on the collateral and is expected to be collected in full and the B note represents the portion of the original loan where there is a shortfall in value and is fully charged-off. The A/B note balance is comprised of the A note balance only. A notes are not disclosed as TDRs in subsequent years after the year of restructuring if the restructuring agreement specifies an interest rate equal to or greater than the rate that the Company was willing to accept at the time of the restructuring for a new loan with comparable risk, the loan is not impaired based on the terms specified by the restructuring agreement and has demonstrated a period of sustained performance under the modified terms.
Potential TDRs are individually evaluated and the type of restructuring is selected based on the loan type and the circumstances of the borrower’s financial difficulty in order to maximize the Company’s recovery.  CRE TDRs were restructured through principal and interest reductions, rate reductions, principal deferments, extensions, and other modified terms, for a total of $8.6 million as of December 31, 2014.  C&I TDRs were restructured through extensions, principal deferments, forbearance payments, rate reductions, and other modified terms, for a total of $3.2 million as of December 31, 2014.  Residential TDRs were restructured through principal deferments, extensions, principal and interest reductions, and other modified terms, for a total of $12.0 million as of December 31, 2014.  Consumer TDRs were restructured through other modified terms for a total of $504 thousand as of December 31, 2014.  These modifications had an impact of a reduction or deferment of principal and/or interest collected over the life of the loan, and/or an extended time period of collection of principal and/or interest.
CRE TDRs were primarily modified through A/B note splits, forbearance of payments and principal and/or interest deferment for a total of $17.5 million as of December 31, 2013.  Modifications of C&I TDRs were restructured through extensions, and principal and interest reduction, for a total of $15.6 million as of December 31, 2013.  Residential TDRs modified using A/B note splits totaled $1.1 million as of December 31, 2013.  Consumer TDRs were restructured through maturity extensions for a total of $639 thousand as of December 31, 2013. CRE TDRs modified using A/B note splits, principal reductions, extensions and/or non-market interest changes totaled $9.2 million as of December 31, 2012. C&I TDRs modified using forbearance payments, principal reductions, principal and/or interest deferment and/or maturity extensions totaled $5.0 million as of December 31, 2012. Residential TDRs modified using principal and/or interest deferment and/or rate reductions, extensions, A/B note splits and/or other principal adjustments totaled $33.7 million as of December 31, 2012. Consumer TDRs were restructured through principal deferment totaling $108 thousand as of December 31, 2012.
The following table presents new TDR modifications on the non-covered loan portfolio and include the financial effects of these modifications for the years ended December 31, 2014, 2013, and 2012:
		Loans Modified as TDRs During the Year Ended December 31,
		2014															2013															2012
		Number			Pre-Modification				Post-Modification				Financial				Number			Pre-Modification				Post-Modification				Financial				Number	Pre-Modification		Post-Modification		Financial
		of			Outstanding				Outstanding				Impact (2)				of			Outstanding				Outstanding				Impact (2)				of	Outstanding		Outstanding		Impact (2)
		Contracts			Recorded				Recorded								Contracts			Recorded				Recorded								Contracts	Recorded		Recorded
					Investment				Investment (1)											Investment				Investment (1)									Investment		Investment (1)
		($ in thousands)
CRE:
Income producing		6			$	8,829			$	8,624			$	43			6			$	26,021			$	17,456			$	219			8	$	10,118	$	8,162	$	1,169
Construction		—			$	—			$	—			$	—			—			$	—			$	—			$	—			—	$	—	$	—	$	—
Land		—			$	—			$	—			$	—			—			$	—			$	—			$	—			3	$	1,610	$	1,059	$	395
C&I:
Commercial business		13			$	4,379			$	3,089			$	2,205			6			$	16,220			$	15,624			$	4,274			14	$	5,101	$	4,374	$	560
Trade finance		1			$	190			$	73			$	14			—			$	—			$	—			$	—			2	$	2,510	$	579	$	1,506
Residential:
Single-family		9			$	11,454			$	8,269			$	—			—			$	—			$	—			$	—			12	$	6,227	$	5,556	$	938
Multifamily		6			$	5,471			$	3,705			$	7			1			$	1,093			$	1,071			$	—			16	$	28,736	$	28,153	$	3,344
Consumer:
Other consumer		1			$	509			$	504			$	—			1			$	651			$	639			$	—			1	$	108	$	108	$	—
-1	Includes subsequent payments after modification.
-2	The financial impact includes charge-offs and specific reserves recorded at modification date.
Subsequent to restructuring, a TDR that becomes delinquent, generally beyond 90 days is considered to have defaulted.  The following table presents information for loans modified as TDRs within the previous 12 months that have subsequently defaulted as of December 31, 2014, 2013, and 2012:
		Loans Modified as TDRs that Subsequently Defaulted
		During the Year Ended December 31,
		2014							2013							2012
		Number of			Recorded				Number of			Recorded				Number of			Recorded
		Contracts			Investment				Contracts			Investment				Contracts			Investment
		($ in thousands)
CRE:
Income producing		—			$	—			—			$	—			1			$	271
Construction		—			$	—			—			$	—			—			$	—
Land		—			$	—			—			$	—			—			$	—
C&I:
Commercial business		1			$	957			1			$	570			2			$	33
Trade finance		—			$	—			—			$	—			—			$	—
Residential:
Single-family		—			$	—			—			$	—			2			$	2,830
Multifamily		—			$	—			—			$	—			1			$	378
Consumer:
Other consumer		—			$	—			1			$	639			—			$	—
TDRs may be designated as performing or nonperforming.  A TDR may be designated as performing if the loan has demonstrated sustained performance under the modified terms.  The period of sustained performance may include the periods prior to modification if prior performance met or exceeded the modified terms.  A loan will remain on nonaccrual status until the borrower demonstrates a sustained period of performance, generally six consecutive months of payments.  The Company had $68.3 million and $71.8 million in total performing restructured loans as of December 31, 2014 and 2013, respectively.  Nonperforming restructured loans were $20.7 million and $11.1 million as of December 31, 2014 and 2013, respectively.  Included as TDRs were $2.9 million and $4.3 million of performing A/B notes as of December 31, 2014 and 2013, respectively.
Performing TDRs as of December 31, 2014 were comprised of $28.4 million in CRE loans, $16.2 million in C&I loans, $22.5 million in residential loans and $1.2 million in consumer loans.  Performing TDRs as of December 31, 2013 were comprised of $37.6 million in CRE loans, $16.7 million in C&I loans, $17.4 million in residential loans and $108 thousand in consumer loans.  Nonperforming TDRs as of December 31, 2014 were comprised of $8.2 million in CRE loans, $5.5 million in C&I loans, $7.0 million in residential loans and no consumer loans.  Nonperforming TDRs as of December 31, 2013 were comprised of $3.4 million in CRE loans, $3.5 million in C&I loans, $3.6 million in residential loans and $639 thousand in consumer loans.
TDRs are included in the impaired loan quarterly valuation allowance process.  See the sections below on Impaired Loans and Allowance for Loan Losses for the complete discussion.  All portfolio segments of TDRs are reviewed for necessary specific reserves in the same manner as impaired loans of the same portfolio segment which have not been identified as TDRs.  The modification of the terms of each TDR is considered in the current impairment analysis of the respective TDR.  For all portfolio segments of delinquent TDRs, when the restructured loan is uncollectible and its fair value is less than the recorded investment in the loan, the deficiency is charged-off against the allowance for loan losses.  If the loan is a performing TDR, the deficiency is included in the specific allowance, as appropriate. As of December 31, 2014, the allowance for loan losses associated with TDRs was $13.1 million for performing TDRs and $1.9 million for nonperforming TDRs. As of December 31, 2013, the allowance for loan losses associated with TDRs was $13.0 million for performing TDRs and $836 thousand for nonperforming TDRs. The amount of additional funds committed to lend to borrowers whose terms have been modified were immaterial as of December 31, 2014 and 2013.
Impaired Loans
A loan is considered impaired when, based on current information and events, it is probable that the Company will be unable to collect all scheduled payments of principal or interest due according to the original contractual terms of the loan agreement. The Company’s loans are grouped into heterogeneous and homogeneous (mostly consumer loans) categories. Classified loans in the heterogeneous category are identified and evaluated for impairment on an individual basis. The Company considers loans individually reviewed to be impaired if, based on current information and events, it is probable the Company will not be able to collect all amounts due according to the original contractual terms of the loan agreement. Impaired loans are measured based on the present value of expected future cash flows discounted at the loan’s effective interest rate or, as an expedient, at the loan’s observable market price or the fair value of the collateral if the loan is collateral dependent, less costs to sell. When the value of an impaired loan is less than the recorded investment in the loan and the loan is classified as nonperforming and uncollectible, the deficiency is charged-off against the allowance for loan losses. Impaired loans exclude the homogenous consumer loan portfolio which is evaluated collectively for impairment. Impaired loans include non-covered loans held for investment on nonaccrual status, regardless of the collateral coverage, and loans modified in a TDR.
As of December 31, 2014 and 2013, impaired non-covered loans totaled $154.1 million and $183.5 million, respectively. The following tables present the Company's impaired non-covered loans as of December 31, 2014 and 2013:
		Unpaid				Recorded				Recorded				Total				Related
		Principal				Investment				Investment				Recorded				Allowance
		Balance				With No				With				Investment (1)
						Allowance				Allowance
		(In thousands)
As of December 31, 2014
CRE:
Income producing		$	57,805			$	34,399			$	15,646			$	50,045			$	1,581
Construction		6,888				6,888				—				6,888				—
Land		13,291				2,838				5,622				8,460				1,906
C&I:
Commercial business		42,396				10,552				25,717				36,269				15,174
Trade finance		280				—				274				274				28
Residential:
Single-family		17,838				5,137				11,398				16,535				461
Multifamily		37,624				21,500				12,890				34,390				313
Consumer:
Other consumer		1,259				1,151				108				1,259				1
Total		$	177,381			$	82,465			$	71,655			$	154,120			$	19,464
		Unpaid				Recorded				Recorded				Total				Related
		Principal				Investment				Investment				Recorded				Allowance
		Balance				With No				With				Investment (1)
						Allowance				Allowance
		(In thousands)
As of December 31, 2013
CRE:
Income producing		$	73,777			$	39,745			$	25,523			$	65,268			$	5,976
Construction		6,888				6,888				—				6,888				—
Land		17,390				4,372				7,908				12,280				2,082
C&I:
Commercial business		48,482				10,850				27,487				38,337				13,787
Trade finance		2,771				438				752				1,190				752
Residential:
Single-family		15,814				13,585				1,588				15,173				207
Multifamily		43,821				30,899				10,215				41,114				1,339
Consumer:
Student loans		1,749				1,681				—				1,681				—
Other consumer		1,945				1,546				—				1,546				—
Total		$	212,637			$	110,004			$	73,473			$	183,477			$	24,143
-1	Excludes $10.1 million and $17.7 million of covered non-accrual loans as of December 31, 2014 and December 31, 2013, respectively, accounted for under ASC 310-10, of which some loans have additional partial balances accounted for under ASC 310-30.
The following table present the average recorded investment in impaired loans and the amount of interest income recognized on impaired loans by portfolio segment:
		Year Ended December 31,
		2014								2013
		Average				Recognized				Average				Recognized
		recorded				interest				recorded				interest
		investment				income (1)				investment				income (1)
		(In thousands)
CRE:
Income producing		$	54,544			$	1,249			$	71,856			$	2,480
Construction		6,888				—				6,888				—
Land		8,633				298				12,453				496
C&I:
Commercial business		36,528				833				38,294				735
Trade finance		336				15				1,603				11
Residential:
Single-family		16,413				342				15,322				154
Multifamily		37,128				830				35,799				850
Consumer:
Student loans		—				—				1,664				—
Other consumer		1,259				47				1,561				4
Total impaired loans (excluding PCI)		$	161,729			$	3,614			$	185,440			$	4,730
-1	Includes interest recognized on accruing TDRs.  Interest payments received on nonaccrual loans are reflected as a reduction of principal and not as interest income.
Allowance for Loan Losses
The allowance consists of specific reserves and a general reserve. The Company’s loans fall into heterogeneous and homogeneous (mostly consumer loans) categories. Impaired loans are subject to specific reserves. Loans in the homogeneous category, as well as non-impaired loans in the heterogeneous category, are evaluated as part of the general reserve. The general reserve is calculated by utilizing both quantitative and qualitative factors. There are different qualitative risks for the loans in each portfolio segment. The residential and CRE segments’ predominant risk characteristic is the collateral and the geographic location of the property collateralizing the loan. The risk is qualitatively assessed based on the change in the real estate market in those geographic areas. The C&I segment’s predominant risk characteristics are the global cash flows of the borrowers and guarantors, and economic and market conditions. Consumer loans, excluding the student loan portfolio guaranteed by the U.S. Department of Education, are largely comprised of HELOCs for which the predominant risk characteristic is the real estate collateral securing the loans.
The Company’s methodology to determine the overall appropriateness of the allowance is based on a classification migration model and qualitative considerations. The migration model examines pools of loans having similar characteristics and analyzes their loss rates over a historical period. The Company assigns loss rates to each loan grade within each pool of loans. Loss rates derived by the migration model are based predominantly on historical loss trends that may not be entirely indicative of the actual or inherent loss potential. As such, the Company utilizes qualitative and environmental factors as adjusting mechanisms to supplement the historical results of the classification migration model. Qualitative considerations include, but are not limited to, prevailing economic or market conditions, relative risk profiles of various loan segments, volume concentrations, growth trends, delinquency and nonaccrual status, problem loan trends, and geographic concentrations. Qualitative and environmental factors are reflected as percentage adjustments and are added to the historical loss rates derived from the classified asset migration model to determine the appropriate allowance for each loan pool.
When determined uncollectible, it is the Company’s policy to promptly charge-off the difference in the outstanding loan balance and the fair value of the collateral or the discounted value of expected cashflows. Recoveries are recorded when payment is received on loans that were previously charged-off through the allowance for loan losses. Allocation of a portion of the allowance to one segment of the loan portfolio does not preclude its availability to absorb losses in other segments.
The following tables present a summary of the activity in the allowance for loan losses on non-covered loans for the years ended December 31, 2014, 2013 and 2012:
		CRE				C&I				Residential				Consumer				Unallocated				Total
		(In thousands)
Year Ended December 31, 2014
Beginning balance		$	64,677			$	115,184			$	50,717			$	11,352			$	—			$	241,930
Provision for (reversal of) loan losses		6,107				40,371				(8,168		)		4,240				1,575				44,125
Allowance for unfunded loan commitments and letters of credit		—				—				—				—				(1,575		)		(1,575		)
Charge-offs		(3,294		)	(1)	(29,592		)		(1,103		)		(5,793		)		—				(39,782		)
Recoveries		1,982				8,635				2,410				449				—				13,476
Net (charge-offs) recoveries		(1,312		)		(20,957		)		1,307				(5,344		)		—				(26,306		)
Ending balance		$	69,472			$	134,598			$	43,856			$	10,248			$	—			$	258,174
Ending balance allocated to:
Individually evaluated for impairment		$	3,487			$	15,202			$	774			$	1			$	—			$	19,464
Collectively evaluated for impairment		65,695				119,396				43,082				10,247				—				238,420
Acquired with deteriorated credit quality		290				—				—				—				—				290
Ending balance		$	69,472			$	134,598			$	43,856			$	10,248			$	—			$	258,174
(1) Includes a charge-off of $523 thousand related to PCI loans acquired from MetroCorp.
		CRE				C&I				Residential				Consumer				Unallocated				Total
	(In thousands)
Year Ended December 31, 2013
Beginning balance		$	69,856			$	105,376			$	49,349			$	4,801			$	—			$	229,382
(Reversal of) provision for loan losses		(6,615		)		12,821				1,918				8,055				2,157				18,336
Allowance for unfunded loan commitments and letters of credit		—				—				—				—				(2,157		)		(2,157		)
Charge-offs		(3,357		)		(7,405		)		(3,197		)		(2,385		)		—				(16,344		)
Recoveries		4,793				4,392				2,647				881				—				12,713
Net recoveries (charge-offs)		1,436				(3,013		)		(550		)		(1,504		)		—				(3,631		)
Ending balance		$	64,677			$	115,184			$	50,717			$	11,352			$	—			$	241,930
Ending balance allocated to:
Individually evaluated for impairment		$	8,058			$	14,539			$	1,546			$	—			$	—			$	24,143
Collectively evaluated for impairment		56,619				100,645				49,171				11,352				—				217,787
Ending balance		$	64,677			$	115,184			$	50,717			$	11,352			$	—			$	241,930
		CRE				C&I				Residential				Consumer				Unallocated				Total
	(In thousands)
Year Ended December 31, 2012
Beginning balance		$	66,457			$	87,020			$	52,180			$	4,219			$	—			$	209,876
Provision for (reversal of) loan losses		20,977				35,204				3,255				2,295				(1,563		)		60,168
Allowance for unfunded loan commitments and letters of credit		—				—				—				—				1,563				1,563
Charge-offs		(27,060		)		(21,818		)		(7,700		)		(1,824		)		—				(58,402		)
Recoveries		9,482				4,970				1,614				111				—				16,177
Net (chargeoffs) recoveries		(17,578		)		(16,848		)		(6,086		)		(1,713		)		—				(42,225		)
Ending balance		$	69,856			$	105,376			$	49,349			$	4,801			$	—			$	229,382
Ending balance allocated to:
Individually evaluated for impairment		$	5,561			$	2,835			$	3,131			$	—			$	—			$	11,527
Collectively evaluated for impairment		64,295				102,541				46,218				4,801				—				217,855
Ending balance		$	69,856			$	105,376			$	49,349			$	4,801			$	—			$	229,382
The following tables present the Company’s recorded investments in total non-covered loans receivable as of December 31, 2014 and 2013 related to each balance in the allowance for loan losses by portfolio segment and disaggregated on the basis of the Company’s impairment methodology:
		CRE				C&I				Residential				Consumer				Total
		(In thousands)
31-Dec-14
Individually evaluated for impairment		$	65,393			$	36,543			$	50,925			$	1,259			$	154,120
Collectively evaluated for impairment		5,977,437				7,796,239				4,768,541				1,455,384				19,997,601
Acquired with deteriorated credit quality		91,216				5,312				1,202				—				97,730
Ending balance		$	6,134,046			$	7,838,094			$	4,820,668			$	1,456,643			$	20,249,451
		CRE				C&I				Residential				Consumer				Total
		(In thousands)
31-Dec-13
Individually evaluated for impairment		$	84,436			$	39,527			$	56,287			$	3,227			$	183,477
Collectively evaluated for impairment		4,500,641				5,320,666				4,129,022				1,544,511				15,494,840
Ending balance		$	4,585,077			$	5,360,193			$	4,185,309			$	1,547,738			$	15,678,317
Allowance for Unfunded Loan Commitments, Off-Balance Sheet Credit Exposures and Recourse Provisions
The allowance for unfunded loan commitments, off-balance sheet credit exposures, and recourse provisions is maintained at a level believed by management to be sufficient to absorb estimated probable losses related to these unfunded credit facilities. The determination of the adequacy of the allowance is based on periodic evaluations of the unfunded credit facilities including an assessment of the probability of commitment usage, credit risk factors for loans outstanding to these same customers, and the terms and expiration dates of the unfunded credit facilities. As of December 31, 2014 and 2013, the allowance for unfunded loan commitments, off-balance sheet credit exposures, and recourse provisions amounted to $12.7 million and $11.3 million, respectively. Net adjustments to the allowance for unfunded loan commitments, off-balance sheet credit exposures, and recourse provisions are included in the provision for loan losses.
Loans serviced for others amounted to $1.19 billion and $1.35 billion as of December 31, 2014 and 2013, respectively. These represent loans that have either been sold or securitized for which the Company continues to provide servicing or has limited recourse. The majority of these loans were residential and C&I as of December 31, 2014 and residential and CRE as of December 31, 2013. Of the total allowance for unfunded loan commitments, off-balance sheet credit exposures, and recourse provisions, $2.2 million and $3.2 million pertain to loans that were sold or securitized with recourse as of December 31, 2014 and 2013, respectively. For complete discussion and disclosure see Note 15 to the Company’s consolidated financial statements.
Accretable Yield
The following table presents the changes in the accretable yield for the PCI loans acquired from MetroCorp for the year ended December 31, 2014:
				Year Ended
				31-Dec-14
				(In thousands)
Beginning balance				$	—
Additions				6,745
Accretion				(4,960		)
Changes in expected cash flows				3,379
Ending Balance				$	5,164

AFFORDABLE_HOUSING_PARTNERSHIP

AFFORDABLE HOUSING PARTNERSHIPS AND OTHER TAX CREDIT INVESTMENTS	12 Months Ended
	Dec. 31, 2014
AFFORDABLE HOUSING PARTNERSHIPS AND OTHER TAX CREDIT INVESTMENTS
AFFORDABLE HOUSING PARTNERSHIPS AND OTHER TAX CREDIT INVESTMENTS	NOTE 10 — AFFORDABLE HOUSING PARTNERSHIPS AND OTHER TAX CREDIT INVESTMENTS
	The Community Reinvestment Act (“CRA”) encourages banks to meet the credit needs of their communities for housing and other purposes, particularly in neighborhoods with low or moderate incomes.  The Company invests in certain affordable housing limited partnerships that qualify for CRA credits. Such limited partnerships are formed to develop and operate apartment complexes designed as high-quality affordable housing for lower income tenants throughout the United States. Each of the partnerships must meet the regulatory requirements for affordable housing for a minimum 15-year compliance period to fully utilize the tax credits. The Company also invests in other investments that qualify for CRA credits. In addition, the Company invests in eligible projects that qualify for historic and energy tax credits. Investments in these other tax credits help promote the development of renewable energy sources and rehabilitation of historic buildings and economic revitalization of the surrounding areas.
	The Company is not the primary beneficiary in these partnerships and, therefore, is not required to consolidate these entities on its financial statements. Depending on the ownership percentage and the influence the Company has on the limited partnership, the Company uses either the equity method or cost method of accounting. As of December 31, 2014, a majority of these investments are accounted under the equity method. If the partnerships cease to qualify during the compliance period, the credits may be denied for any period in which the projects are not in compliance and a portion of the credits previously taken may be subject to recapture with interest. Investments in affordable housing partnerships, net were $178.7 million and $164.8 million as of December 31, 2014 and 2013, respectively. CRA and other tax credit investments were $110.1 million and $70.2 million as of December 31, 2014 and 2013, respectively, and are included in other assets in the consolidated balance sheets.
	The Company has unfunded commitments related to the affordable housing and other tax credit investments that are payable on demand. Total unfunded commitments for these investments were $114.7 million and $73.1 million as of December 31, 2014 and 2013, respectively, and are included in accrued expenses and other liabilities in the consolidated balance sheets.
	The Company's usage of affordable housing partnerships and other tax credit investments' federal tax credits totaled $84.8 million, $34.2 million and $18.7 million for the years ended December 31, 2014, 2013 and 2012, respectively. Affordable housing and other tax credit investments amortization was $75.7 million, $27.3 million and $18.1 million for the years ended December 31, 2014, 2013 and 2012, respectively. The Company's remaining tax credits approximated $193.8 million as of December 31, 2014.

GOODWILL_AND_OTHER_INTANGIBLE_

GOODWILL AND OTHER INTANGIBLE ASSETS	12 Months Ended
	Dec. 31, 2014
GOODWILL AND OTHER INTANGIBLE ASSETS
GOODWILL AND OTHER INTANGIBLE ASSETS	NOTE 11 — GOODWILL AND OTHER INTANGIBLE ASSETS
	Goodwill
	As of December 31, 2014 and 2013, the carrying amounts of goodwill were $469.4 million and $337.4 million, respectively. The increase of $132.0 million to goodwill was due to the acquisition of MetroCorp as discussed in Note 2 to the Company’s consolidated financial statements.
	The Company has identified three business divisions, Retail Banking, Commercial Banking, and Other, that meet the criteria of an operating segment in accordance with GAAP. The Company determined that there were no additional reporting units below each operating segment and therefore the reporting units are equivalent to the operating segments. For complete discussion and disclosure see Note 20 to the Company’s consolidated financial statements presented elsewhere in this report.
	The Company performed its annual impairment test as of December 31, 2014 to determine whether and to what extent, if any, recorded goodwill was impaired. The Company uses a combined income and market approach to determine the fair value of the reporting units. Under the income approach, the Company provided a net income projection for the next three years plus a terminal growth rate that was used to calculate the discounted cash flows and the present value of the reporting units. Under the market approach, the fair value was calculated using the current fair values of comparable peer banks of similar size, geographic footprint and focus. The market capitalizations and multiples of these peer banks were used to calculate the market price of the Company and each reporting unit. The fair value was also subject to a control premium adjustment, which is the cost savings that a purchaser of the reporting units could achieve by eliminating duplicative costs. Under the combined income and market approaches, the value from each approach was weighted based on management's perceived risk of each approach to determine the fair value. As a result of this analysis, the Company determined that there was no goodwill impairment as of December 31, 2014 as the fair values of all reporting units exceeded the current carrying amounts of the goodwill. No assurance can be given that goodwill will not be written down in future periods.
	The following table presents changes in the carrying amount of goodwill for the years ended December 31, 2014 and 2013:
		Year Ended December 31,
		2014		2013
		(In thousands)
	Beginning balance	$	337,438	$	337,438
	Addition from the MetroCorp acquisition(1)	131,995		—
	Ending Balance	$	469,433	$	337,438
	(1) Includes $11.0 million of tax and BOLI adjustments recorded in the fourth quarter of 2014.
	Premiums on Acquired Deposits
	Premiums on acquired deposits represent the intangible value of depositor relationships resulting from deposit liabilities assumed in various acquisitions. These intangibles are tested for impairment on an annual basis, or more frequently as events occur, or as current circumstances and conditions warrant. As of December 31, 2014 and 2013, the gross carrying amount of premiums on acquired deposits were $108.8 million and $100.2 million, respectively, and the related accumulated amortization totaled $63.5 million and $53.3 million, respectively. A premium on acquired deposits of $8.6 million was recorded due to the acquisition of MetroCorp as discussed in Note 2 to the Company’s consolidated financial statements. The weighted-average amortization period related to MetroCorp's premium on acquired deposits is eight years.
	The Company amortizes premiums on acquired deposits based on the projected useful lives of the related deposits. Amortization expense of premiums on acquired deposits was $10.2 million, $9.4 million and $10.9 million for the years ended December 31, 2014, 2013 and 2012, respectively. The Company did not record any impairment write-downs on deposit premiums for the years ended December 31, 2014, 2013 and 2012.
	The following table presents the estimated future amortization expense of premiums on acquired deposits for the succeeding five years and thereafter:
	Estimates For The Years Ending December 31,	Amount
		(In thousands)
	2015	$	9,234
	2016	8,086
	2017	6,935
	2018	5,883
	2019	4,864
	Thereafter	10,307
	Total	$	45,309

CUSTOMER_DEPOSIT_ACCOUNTS

CUSTOMER DEPOSIT ACCOUNTS	12 Months Ended
	Dec. 31, 2014
CUSTOMER DEPOSIT ACCOUNTS
CUSTOMER DEPOSIT ACCOUNTS	NOTE 12 — CUSTOMER DEPOSIT ACCOUNTS
	Customer deposit account balances are summarized as follows:
		December 31,
		2014		2013
		(In thousands)
	Noninterest-bearing demand	$	7,381,030	$	5,821,899
	Interest-bearing checking	2,545,618		1,749,479
	Money market accounts	6,318,120		5,653,412
	Savings deposits	1,651,267		1,363,780
	Total core deposits	17,896,035		14,588,570
	Time deposits:
	Less than $100,000	1,662,046		1,678,850
	$100,000 or greater	4,450,693		4,145,498
	Total time deposits	6,112,739		5,824,348
	Total deposits	$	24,008,774	$	20,412,918
	Time deposits in the $100 thousand or greater category included $133.3 million and $169.7 million of deposits held by the Company’s foreign branch located in Hong Kong as of December 31, 2014 and 2013, respectively.
	As of December 31, 2014, the scheduled maturities of time deposits are as follows:
		$100,000 or		Less Than		Total
		Greater		$100,000
		(In thousands)
	2015	$	3,513,958	$	1,397,648	$	4,911,606
	2016	318,791		164,061		482,852
	2017	189,195		44,944		234,139
	2018	168,252		34,579		202,831
	2019	142,492		20,782		163,274
	Thereafter	118,005		32		118,037
	Total	$	4,450,693	$	1,662,046	$	6,112,739
	As of December 31, 2014, time deposits within the Certificate of Deposit Account Registry Service (“CDARS”) program decreased to $180.0 million, compared to $203.3 million at December 31, 2013. The CDARS program allows customers with deposits in excess of FDIC-insured limits to obtain full coverage on time deposits through a network of banks within the CDARS program. Additionally, the Company has partnered with another financial institution and offers a retail sweep product for non-time deposit accounts to provide added deposit insurance coverage for deposits in excess of FDIC-insured limits. Deposits gathered through these programs are considered brokered deposits under current regulatory reporting guidelines.

FEDERAL_HOME_LOAN_BANK_ADVANCE

FEDERAL HOME LOAN BANK ADVANCES AND LONG-TERM DEBT	12 Months Ended
	Dec. 31, 2014
FEDERAL HOME LOAN BANK ADVANCES AND LONG-TERM DEBT
FEDERAL HOME LOAN BANK ADVANCES AND LONG-TERM DEBT	NOTE 13 — FHLB ADVANCES AND LONG-TERM DEBT
	FHLB Advances— Total carrying amounts of FHLB advances were $317.2 million and $315.1 million with weighted average interest rates of 0.58% and 0.61%, as of December 31, 2014 and 2013, respectively. As of December 31, 2014, FHLB advances that matures during the next five years are as follows: 2015 to 2018 — $0 million; 2019 — $79.4 million; 2020 and thereafter — $237.8 million. As of December 31, 2014 and 2013, FHLB advances had interest rates ranging from 0.40% to 0.64%, which are floating and reset monthly or quarterly based on LIBOR. There were no outstanding overnight borrowings as of December 31, 2014 and 2013. All advances as of December 31, 2014 and 2013 were secured by real estate loans.
	The Company’s available borrowing capacity from FHLB totaled $5.54 billion and $3.70 billion as of December 31, 2014 and 2013, respectively. The Company’s available borrowing capacity from the FHLB is derived from its portfolio of loans that are pledged to the FHLB deducted by its outstanding FHLB advances. As of December 31, 2014 and 2013, the Company had additional available borrowing capacity of $3.03 billion and $1.42 billion, respectively, from the Federal Reserve Bank’s discount window derived from its portfolio of loans that are pledged to the Federal Reserve Bank.
	Long-Term Debt
	The following table presents the components of long-term debt as of December 31, 2014 and 2013:
			December 31,
			2014			2013
			(In thousands)
	Junior subordinated debt		$	145,848		$	126,868
	Term loan		80,000			100,000
	Total long-term debt		$	225,848		$	226,868
	Junior Subordinated Debt—As of December 31, 2014, the Company has six statutory business trusts for the purpose of issuing junior subordinated debt to third party investors. The junior subordinated debt was issued in connection with the Company's various pooled trust preferred securities offerings. Junior subordinated debt is recorded as a component of long-term debt and considers the value of the common stock issued by the Trusts to the Company in conjunction with these transactions. The common stock is recorded in other assets for the amount issued in connection with these junior subordinated debt issuances. Junior subordinated debt outstanding, issued by the Trusts to the Company, totaled $148.0 million as of December 31, 2014, compared to $123.0 million as of December 31, 2013. During 2014, the junior subordinated debt of one statutory business trust for $10.0 million, with related common stock of $310 thousand, was redeemed in order to reduce higher interest-bearing debt and due to the phase-out of trust preferred securities as Tier I regulatory capital. This decrease was offset by a junior subordinated debt recorded due to the acquisition of MetroCorp during the first quarter of 2014. As of December 31, 2014, the MetroCorp junior subordinated debt was $35.0 million, before reduction of a purchase accounting adjustment of $6.8 million, with related common stock of $1.1 million. The total related common stock outstanding, issued by the Trusts to the Company amounted to $4.6 million and $3.9 million as of December 31, 2014 and 2013, respectively.
	The proceeds from these issuances represent liabilities of the Company to the Trusts and are reported in the consolidated balance sheets as a component of long-term debt. Interest payments on these securities are made either quarterly or semi-annually and are deductible for tax purposes. Under the Dodd-Frank Wall Street Reform and Consumer Protection Act, bank holding companies with more than $15 billion in total consolidated assets are no longer able to include trust preferred securities as Tier I regulatory capital following a phase-out period, which commenced in 2013 with phase-out complete by 2016. The junior subordinated debt is being phased out 25% each year, over the four year period, from Tier I capital into Tier II capital for regulatory purposes.
	1
	The following table summarizes pertinent information related to outstanding junior subordinated debt issued by each Trust as of December 31, 2014 and 2013:
	Trust Name		Maturity Date (1)		Stated	Rate as of		December 31,
					Interest Rate	December 31, 2014		2014		2013
								($ in thousands)
	East West Capital Trust IV		Jul-34		3-month Libor + 2.55%	—		$	—	$	10,000
	East West Capital Trust V		Nov-34		3-month Libor + 1.80%	2.03	%	15,000		15,000
	East West Capital Trust VI		Sep-35		3-month Libor + 1.50%	1.74	%	20,000		20,000
	East West Capital Trust VII		Jun-36		3-month Libor + 1.35%	1.59	%	30,000		30,000
	East West Capital Trust VIII		Jun-37		3-month Libor + 1.40%	1.64	%	18,000		18,000
	East West Capital Trust IX		Sep-37		3-month Libor + 1.90%	2.14	%	30,000		30,000
	Metro Bank Trust		Dec-35		3-month Libor + 1.55%	1.79	%	35,000		—
	Total							$	148,000	$	123,000
	-1	All of the above debt instruments are subject to various call options.
	Term Loan—In 2013, the Company entered into a three-year term loan agreement for $100.0 million. The three-year term loan is payable in quarterly installments of $5.0 million starting on March 31, 2014 and with a $50.0 million final repayment at maturity on July 1, 2016. The interest rate was 1.81% as of December 31, 2014, which is based on the three-month LIBOR plus 150 basis points. The outstanding balance of the term loan was $80.0 million and $100.0 million as of December 31, 2014 and 2013, respectively.  The term loan is included in long-term debt in the consolidated balance sheets.

INCOME_TAXES

INCOME TAXES	12 Months Ended
	Dec. 31, 2014
INCOME TAXES
INCOME TAXES	NOTE 14 — INCOME TAXES
	Provision for income taxes was $73.0 million in 2014, representing an effective tax rate of 17.6%, compared to $130.8 million, representing an effective tax rate of 30.7% and $143.9 million, representing an effective tax rate of 33.8% for 2013 and 2012, respectively. The lower effective tax rate in 2014 compared to 2013 and 2012, was mainly due to the additional purchases of affordable housing, historic and renewable energy tax credit investments. Included in the income tax expense recognized during 2014, 2013 and 2012 was $85.7 million, $35.0 million and $18.7 million, respectively, of tax credits generated mainly from investments in affordable housing partnerships and other tax credit investments.
	Management regularly reviews the Company’s tax positions and deferred tax assets. Factors considered in this analysis include future reversals of existing temporary differences, future taxable income exclusive of reversing differences, taxable income in prior carryback years, and tax planning strategies. The Company accounts for income taxes using the asset and liability approach, the objective of which is to establish deferred tax assets and liabilities for the temporary differences between the financial reporting basis and the tax basis of the Company’s assets and liabilities at enacted rates expected to be in effect when such amounts are realized and settled. Based on the available evidence, Management has concluded that it is more likely than not that all of the benefit of the deferred tax assets will be realized, with the exception of the deferred tax assets related to certain state NOL carryforwards. Accordingly, a valuation allowance has been recorded for these amounts.
	As of December 31, 2014 and 2013, the Company had a net deferred tax asset of $384.4 million and $255.5 million, respectively.
	The following table presents the components of provision for income taxes for the years indicated:
		Year Ended December 31,
		2014				2013				2012
		(In thousands)
	Current income tax expense:
	Federal	$	153,211			$	131,236			$	148,572
	State	70,527				44,389				2,316
	Foreign	3,846				208				5,704
	Total current income tax expense	227,584				175,833				156,592
	Deferred income tax benefit:
	Federal	(116,241		)		(32,963		)		(38,749		)
	State	(37,665		)		(13,677		)		26,099
	Foreign	(706		)		1,612				—
	Total deferred income tax benefit	(154,612		)		(45,028		)		(12,650		)
	Provision for income taxes	$	72,972			$	130,805			$	143,942
	The difference between the effective tax rate implicit in the consolidated financial statements and the statutory federal income tax rate can be attributed to the following:
		Year Ended December 31,
		2014			2013			2012
	Federal income tax provision at statutory rate	35	%		35	%		35	%
	State franchise taxes, net of federal tax effect	5.1			4.7			4.3
	Tax credits	(21.5	)		(8.4	)		(5.3	)
	Other, net	(1.0	)		(0.6	)		(0.2	)
	Effective income tax rate	17.6	%		30.7	%		33.8	%
	The Company recognizes investment tax credits from low income housing and other investments in the year the credit arises under the flow-through method of accounting. The tax effects of temporary differences that give rise to significant portions of the deferred tax assets (liabilities) are presented below:
		December 31,
		2014														2013
		Federal				State				Foreign			Total			Federal			State			Foreign		Total
		(In thousands)
	Deferred tax liabilities:
	Core deposit intangibles	$	(15,748	)		$	(4,513	)		$	—		$	(20,261	)	$	(16,422	)	$	(4,642	)	$	—	$	(21,064	)
	Affordable housing partnerships and other investments	—				—				—			—			(14,158		)	(1,730		)	—		(15,888		)
	Fixed assets	(16,615		)		(4,101		)		—			(20,716		)	(15,594		)	(3,879		)	—		(19,473		)
	Federal Housing Loan Bank stock	(5,064		)		(1,475		)		—			(6,539		)	(11,337		)	(3,224		)	—		(14,561		)
	Deferred loan fees	(1,587		)		(454		)		—			(2,041		)	(1,976		)	(557		)	—		(2,533		)
	Purchased loan discounts	(51		)		(15		)		—			(66		)	(98		)	(28		)	—		(126		)
	State taxes	(8,244		)		—				—			(8,244		)	(1,079		)	—			—		(1,079		)
	Section 597 gain	(2,063		)		(64		)		—			(2,127		)	(48,370		)	(1,317		)	—		(49,687		)
	FDIC receivable	—				—				—			—			(245,907		)	(6,695		)	—		(252,602		)
	Acquired debt	(2,237		)		1,369				—			(868		)	(10,812		)	(1,042		)	—		(11,854		)
	Other, net	(1,652		)		(473		)		—			(2,125		)	(6,805		)	923			—		(5,882		)
	Total gross deferred tax (liabilities)	(53,261		)		(9,726		)		—			(62,987		)	(372,558		)	(22,191		)	—		(394,749		)
	Deferred tax assets:
	Affordable housing partnerships and other investments	1,768				4,870				—			6,638			—			—			—		—
	Allowance for loan losses and REO reserves	93,749				23,615				1,409			118,773			93,018			23,046			—		116,064
	FDIC receivable and clawback	36,630				11,736				—			48,366			—			—			—		—
	Deferred compensation	16,505				4,785				—			21,290			13,322			3,824			—		17,146
	Mortgage servicing assets	2,570				735				—			3,305			287			81			—		368
	Purchased loan premium	292				84				—			376			424			120			—		544
	Unrealized loss on securities	42,737				12,638				—			55,375			62,535			19,177			—		81,712
	Acquired loans and REOs	139,360				36,678				256			176,294			366,290			26,959			959		394,208
	Other, net	12,189				4,967				97			17,253			30,768			9,709			97		40,574
	Total gross deferred tax assets	345,800				100,108				1,762			447,670			566,644			82,916			1,056		650,616
	Valuation allowance	—				(316		)		—			(316		)	—			(337		)	—		(337		)
	Net deferred tax assets	$	292,539			$	90,066			$	1,762		$	384,367		$	194,086		$	60,388		$	1,056	$	255,530
	Management believes that it is more likely than not that all of the deferred tax assets recorded as of December 31, 2014 will be realized (except to the extent of the recorded valuation allowance) because it expects to have sufficient taxable income in future years to fully realize them. A valuation allowance has been provided for the state NOLs (for states other than California, Georgia, Massachusetts and New York) since management believes that these NOLs may not be fully utilized. As of December 31, 2014, the Bank had state net operating loss carryforwards of approximately $4.0 million. Net deferred tax assets are included in other assets on the consolidated balance sheet presented earlier in this report.
	The following table summarizes the activity related to the Company's unrecognized tax benefits:
		Year Ended December 31,
		2014				2013
		(In thousands)
	Beginning Balance	$	4,677			$	3,457
Additions for tax positions of prior years	343				232
Reductions for tax positions of prior years	—				—
Additions for tax positions of current year					988
Settlements	—				—
Ending Balance	$	5,020			$	4,677
For the years ended December 31, 2014 and 2013, the Company increased the unrecognized tax benefits reserve by $343 thousand and $1.2 million, respectively, for the California enterprise zone net interest deduction. There were no reductions in unrecognized tax benefits for 2014. As of December 31, 2014 and 2013, the liability for uncertain tax positions was $7.2 million and $6.3 million, respectively, which is included in accrued expenses and other liabilities on the consolidated balance sheets presented earlier in this report. Also, for the years ended December 31, 2014 and 2013, the total amount of unrecognized tax benefits that, if recognized, would impact the effective tax rate is $3.3 million and $3.0 million, respectively.
During 2014, the Company closed the Internal Revenue Service (“IRS”) examination of the 2012 tax year with no material changes. Every year, subsequent to 2012, the Company has executed a Memorandum of Understanding (“MOU”) with the IRS to voluntarily participate in the IRS Compliance Assurance Process (“CAP”) where the IRS will assist the Company in identifying and resolving any tax issues that may arise throughout the tax year. The objective of the CAP is to resolve issues in a timely and contemporaneous manner and eliminate the need for a lengthy post-filing examination. The 2013 and 2012 tax return filed in September 2014 and September 2013, respectively received a full acceptance of all tax matters from the IRS. The Company has entered a MOU with the IRS for the 2014 and 2015 tax years. For federal tax purposes, tax years from 2011 and beyond remain open. For California franchise tax purposes, tax years from 2003 and beyond remain open. The states of Alabama, New York and Ohio have initiated audits of East West Bank’s corporate income tax returns through the 2012 tax year. The Company does not believe that the outcome of unresolved issues or claims in any tax jurisdiction is likely to be material to the Company’s financial position, cash flows or results of operations. The Company further believes that adequate provisions have been made for all income tax uncertainties. The Company does not anticipate that the total amount of unrecognized tax benefits will significantly change for the year ended December 31, 2015.
The Company recognizes interest and penalties, if applicable, related to the underpayment of income taxes as a component of income tax expense in the consolidated statement of operations. The Company accrued interest and penalties of $597 thousand, ($744) thousand and $1.2 million for its unrecognized tax positions as of December 31, 2014, 2013 and 2012, respectively. Total interest and penalties accrued as of December 31, 2014 and 2013 were $2.2 million and $1.6 million, respectively, which is included in accrued expenses and other liabilities on the consolidated balance sheets presented earlier in this report.

COMMITMENTS_AND_CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
	Dec. 31, 2014
COMMITMENTS AND CONTINGENCIES.
COMMITMENTS AND CONTINGENCIES	NOTE 15 — COMMITMENTS AND CONTINGENCIES
	Credit Extensions — In the normal course of business, the Company has various outstanding commitments to extend credit that are not reflected in the accompanying consolidated financial statements. While the Company does not anticipate losses as a result of these transactions, commitments to extend credit are included in determining the appropriate level of the allowance for unfunded commitments and credit exposures.
	Loan commitments are agreements to lend to a customer provided there is no violation of any condition established in the agreement. Commitments generally have fixed expiration dates or other termination clauses. Because many of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future funding requirements. As of December 31, 2014 and 2013, undisbursed loan commitments amounted to $3.87 billion and $4.02 billion, respectively. As of December 31, 2014 and 2013 all undisbursed loan commitments are for loans held for investment.
	Commercial letters of credit are issued to facilitate domestic and foreign trade transactions while standby letters of credit (“SBLCs”) are issued to make payments on behalf of customers when certain specified future events occur. As of December 31, 2014 and 2013, commercial and SBLC totaled $1.25 billion and $1.16 billion, respectively. The Company issues SBLC and financial guarantees to support the obligations of its customers to beneficiaries. Based on historical trends, the probability that it will have to make payments under SBLC is low. Additionally, in many cases, the Company holds collateral in various forms against these SBLC. As part of its risk management activities, the Company monitors the creditworthiness of the customer as well as its SBLC exposure; however, if the customer fails to perform the specified obligation to the beneficiary, the beneficiary may draw upon the SBLC by presenting documents that are in compliance with the letter of credit terms. In that event, the Company either repays the money borrowed or advanced, makes payment on account of the indebtedness of the customer or makes payment on account of the default by the customer in the performance of an obligation, to the beneficiary up to the full notional amount of the SBLC. The customer is obligated to reimburse the Company for any such payment. If the customer fails to pay, the Company would, as applicable, liquidate collateral and/or set off accounts.
	Credit card lines are unsecured commitments that are not legally binding. Management reviews credit card lines at least annually and, upon evaluation of the customers’ creditworthiness, the Bank has the right to terminate or change certain terms of the credit card lines.
	The Company uses the same credit policies in making commitments and conditional obligations as in extending loan facilities to customers. It evaluates each customer’s creditworthiness on a case-by-case basis. The amount of collateral obtained, if deemed necessary by the Company upon extension of credit, is based on management’s credit evaluation of the counterparty. Collateral held varies but may include accounts receivable, inventory, property, plant and equipment, and income-producing commercial properties.
	As of December 31, 2014 and 2013, the allowance for unfunded loan commitments, off-balance sheet credit exposures, and recourse provision amounted to $12.7 million and $11.3 million, respectively. These amounts are included in accrued expenses and other liabilities in the accompanying consolidated balance sheets.
	Guarantees — In prior years, the Company sold or securitized loans with recourse in the ordinary course of business. For loans that have been sold or securitized with recourse, the recourse component is considered a guarantee. As such, the Companyis committed to stand ready to perform if the loan defaults and to make payments to remedy the default. As of December 31, 2014, the maximum potential future payment, which is generally the unpaid principal balance of total loans sold or securitized with recourse amounted to $249.8 million and were comprised of $35.5 million in single-family loans with full recourse and $214.3 million in multifamily loans with limited recourse. In comparison, total loans sold or securitized with recourse amounted to $338.8 million as of December 31, 2013, comprised of $42.2 million in single-family loans with full recourse and $296.6 million in multifamily loans with limited recourse. The recourse provision on multifamily loans varies by loan sale and is limited to 4% of the top loss on the underlying loans. The Company’s recourse reserve related to loan sales and securitizations totaled $2.2 million and $3.2 million as of December 31, 2014 and 2013, respectively, and is included in accrued expenses and other liabilities in the accompanying consolidated balance sheets. The Company continues to experience minimal losses from the single-family and multifamily loan portfolios sold or securitized with recourse.
	The Company also sells or securitizes loans without recourse that may have to be subsequently repurchased if a defect that occurred during the loan origination process results in a violation of a representation or warranty made in connection with the securitization or sale of the loan. When a loan sold or securitized to an investor without recourse fails to perform according to its contractual terms, the investor will typically review the loan file to determine whether defects in the origination process occurred and if such defects give rise to a violation of a representation or warranty made to the investor in connection with the sale or securitization. If such a defect is identified, the Company may be required to either repurchase the loan or indemnify the investor for losses sustained. If there are no such defects, the Company has no commitment to repurchase the loan. As of December 31, 2014 and 2013, the amount of loans sold without recourse totaled $781.4 million and $818.2 million, respectively. Total loans securitized without recourse amounted to $162.8 million and $193.8 million as of December 31, 2014 and 2013, respectively. The loans sold or securitized without recourse represent the unpaid principal balance of the Company’s loans serviced for others portfolio.
	Lease Commitments — The Company conducts a portion of its operations utilizing leased premises and equipment under operating leases. Rental expense amounted to $26.2 million, $26.2 million and $22.8 million for the years ended December 31, 2014, 2013 and 2012, respectively.
	Future minimum rental payments under non-cancelable operating leases are estimated as follows:
	Estimates For The Years Ending December 31,	Amount
		(In thousands)
	2015	$	24,076
	2016	19,239
	2017	14,957
	2018	11,389
	2019	9,950
	Thereafter	30,910
	Total	$	110,521
	Litigation — In the ordinary course of the Company’s business, the Company is a party to various legal actions, which the Company believes are incidental to the operation of our business. In accordance with ASC 450, Contingencies, the Company accrues reserves for currently outstanding lawsuits, claims and proceedings when it is probable that a liability has been incurred and the liability can be reasonably estimated. The outcome of litigation and other legal and regulatory matters is inherently uncertain, and it is possible that one or more of the legal or regulatory matters, if any, currently pending or threatened could have a material adverse effect on the Company's liquidity, consolidated financial position, and/or results of operations. Based on the information currently available, advice of counsel and established reserves, the Company believes that the eventual outcome of the matters described below, will not, individually or in the aggregate have a material adverse effect on the Company’s consolidated financial position.
	On September 8, 2014, a jury in the case titled “F&F, LLC and 618 Investment, Inc. v. East West Bank,” Superior Court of the State of California for the County of Los Angeles, Case No. BC462714, delivered a verdict in favor of plaintiff F&F, LLC, which was adjusted down by the court on December 18, 2014 to the amount of $36.6 million.  The case is subject to further legal proceedings including appeal.  The Company continues to appeal but has accrued based on the unfavorable verdict.  As of December 31, 2014, a litigation accrual of $31.6 million has been recorded.
	Other Commitments — The Company has commitments to invest in affordable housing partnerships and other tax credit investments qualifying for community reinvestment tax credits or other types of tax credits. These commitments are payable on demand. As of December 31, 2014 and 2013 these commitments were $114.7 million and $73.1 million, respectively. These commitments are included in accrued expenses and other liabilities on the consolidated balance sheet.

STOCK_COMPENSATION_PLANS

STOCK COMPENSATION PLANS	12 Months Ended
	Dec. 31, 2014
STOCK COMPENSATION PLANS
STOCK COMPENSATION PLANS	NOTE 16 — STOCK COMPENSATION PLANS
	The Company issues stock options and restricted stock awards to employees under share-based compensation plans. During the years ended December 31, 2014, 2013 and 2012, total compensation expense related to stock options and restricted stock awards reduced income before taxes by $13.9 million, $13.5 million and $12.7 million, respectively. The net tax benefit recognized in equity for stock compensation plans was $6.5 million, $5.5 million, and $462 thousand for the years ended December 31, 2014, 2013 and 2012, respectively.
	As of December 31, 2014, there are 3,715,327 shares available to be issued, subject to the Company’s current 1998 Stock Incentive Plan, as amended.
	Stock Options — The Company issues fixed stock options to certain employees, officers, and directors. Stock options are issued at the current market price on the date of grant with a three-year or four-year vesting period and contractual terms of 7 or 10 years. The Company issues new shares upon the exercise of stock options.
	The following table presents the activity for the Company’s stock options as of and for the year ended December 31, 2014:
		Shares		Weighted			Weighted		Aggregate
				Average			Average		Intrinsic
				Exercise			Remaining		Value
				Price			Contractual		(In thousands)
							Term
	Outstanding at beginning of year	406,731		$	26.72
	Granted	—		—
	Exercised	(234,101	)	21.09
	Forfeited	(130,514	)	38.76
	Outstanding at end of year	42,116		$	20.75		0.19 years		$	757
	Vested or expected to vest at year-end	42,116		$	20.75		0.19 years		$	757
	Exercisable at year-end	42,116		$	20.75		0.19 years		$	757
	The fair value of each option granted is estimated on the date of grant using the Black-Scholes option-pricing model with the following assumptions: (1) the expected term (estimated period of time outstanding) of stock options granted is estimated using the historical exercise behavior of employees; (2) the expected volatility is based on historical volatility for a period equal to the stock option’s expected term; (3) the expected dividend yield is based on the Company’s prevailing dividend rate at the time of grant; and (4) the risk-free rate is based on the U.S. Treasury strips in effect at the time of grant equal to the stock option’s expected term. The Company did not issue any stock options during the years ended December 31, 2014, 2013, and 2012.
	The Company received $4.9 million and $1.7 million as of December 31, 2014 and 2013, respectively, in cash proceeds from stock option exercises. The net tax benefit recognized from stock option exercises was $1.4 million for 2014 compared to $48 thousand for 2013.
	The following table presents information about stock options outstanding as of December 31, 2014:
		Options Outstanding							Options Exercisable
	Range of	Number of		Weighted			Weighted		Number of			Weighted
	Exercise Prices	Outstanding		Average			Average		Exercisable			Average
		Options		Exercise			Remaining		Options			Exercise
				Price			Contractual Life					Price
	$10.00 to $14.99	2,365		$	14.95		1.02 years		2,365			$	14.95
	$20.00 to $24.99	39,751		$	21.09		0.14 years		39,751			$	21.09
	$10.00 to $24.99	42,116		$	20.75		0.19 years		42,116			$	20.75
	The following table presents information related to stock options for the years ended December 31, 2014, 2013 and 2012:
		Year Ended December 31,
		2014			2013			2012
	Total intrinsic value of options exercised (in thousands)	$	3,546		$	926		$	978
	Total fair value of options vested (in thousands)	$	—		$	363		$	3,717
	As of December 31, 2013 all stock options are fully vested and all compensation cost related to stock options have been recognized.
	Restricted Stock Awards — In addition to stock options, the Company also grants restricted stock awards to directors, officers and employees. The restricted stock awards fully vest after three to five years of continued employment from the date of grant; some of the awards are also subject to achievement of certain established financial goals. The Company becomes entitled to an income tax deduction in an amount equal to the taxable income reported by the holders of the restricted stock when the restrictions are released and the shares are issued. Restricted stock awards are forfeited if officers and employees terminate employment prior to the lapsing of restrictions or if established financial goals are not achieved. The Company records forfeitures of issued restricted stock as treasury share repurchases.
	The following table presents a summary of the activity for the Company’s time-based and performance-based restricted stock awards as of December 31, 2014, including changes during the year then ended:
		2014
		Restricted Stock Awards
		Time-Based					Performance-Based
		Shares		Weighted			Shares			Weighted
				Average						Average
				Price						Price
	Outstanding at beginning of year	438,508		$	17.79		956,707			$	23.74
	Granted	43,210		33.19			603,697			36.85
	Vested	(343,722	)	15.91			(340,866	)		23.52
	Forfeited	(30,733	)	21.21			(57,228	)		29.71
	Outstanding at end of year	107,263		$	29.01		1,162,310			$	30.32
	During 2014 there were no restricted stock grants to outside directors.
	Restricted stock awards are valued at the closing price of the Company’s stock on the date of award. The weighted average fair values of time-based restricted stock awards granted during the years ended December 31, 2014, 2013 and 2012 were $33.19, $28.55 and $21.66, respectively. The weighted average fair value of performance-based restricted stock awards granted during the year ended December 31, 2014, 2013 and 2012 were $36.85, $25.25 and $22.05, respectively. The total fair value of time-based restricted stock awards vested during 2014, 2013 and 2012 was $12.2 million, $29.4 million and $3.5 million, respectively. The total fair value of performance-based restricted stock award vested during 2014, 2013 and 2012 were $12.6 million, $4.4 million and $4.7 million, respectively.
	As of December 31, 2014, total unrecognized compensation cost related to time-based and performance-based restricted stock awards amounted to $2.3 million and $21.7 million, respectively. This cost is expected to be recognized over a weighted average period of 2.55 years and 1.93 years, respectively.
	Stock Purchase Plan — The Company adopted the 1998 Employee Stock Purchase Plan (the “Purchase Plan”) providing eligible employees of the Company and its subsidiaries participation in the ownership of the Company through the right to purchase shares of its common stock at a discount. The Purchase Plan allows employees to purchase shares at 90% of the per share market price at the date of exercise, with an annual common stock value purchase limitation of $25,000. As of December 31, 2014, the Purchase Plan qualifies as a non-compensatory plan under Section 423 of the Internal Revenue Code and, accordingly, no compensation expense is recognized under the Purchase Plan.
	The Purchase Plan covers a total of 2,000,000 shares of the Company’s common stock. During 2014 and 2013, 58,587 shares totaling $1.9 million and 53,015 shares totaling $1.4 million, respectively, were sold to employees under the Purchase Plan. As of December 31, 2014, there were 694,713 shares available under the Purchase Plan.

EMPLOYEE_BENEFIT_PLANS

EMPLOYEE BENEFIT PLANS	12 Months Ended
	Dec. 31, 2014
EMPLOYEE BENEFIT PLANS
EMPLOYEE BENEFIT PLANS	NOTE 17 — EMPLOYEE BENEFIT PLANS
	The Company sponsors a defined contribution plan for the benefit of its employees. The Company’s contributions to the plan are determined annually by the Board of Directors in accordance with plan requirements. For tax purposes, eligible participants may contribute up to the dollar limit imposed by the Internal Revenue Service each year. For plan years ended December 31, 2014, 2013 and 2012, the Company contributed $5.9 million, $4.3 million and $3.5 million, respectively.
	During 2002, the Company adopted a Supplemental Executive Retirement Plan (“SERP”). The SERP meets the definition of a pension plan per ASC 715-30, Compensation—Retirement Benefits – Defined Benefit Plans—Pension, pursuant to which the Company will pay supplemental pension benefits to certain executive officers designated by the Board of Directors upon retirement based upon the officers’ years of service and compensation. For the years ended December 31, 2014, 2013, and 2012, $583 thousand, $644 thousand and $787 thousand, respectively, of benefits were accrued. The SERP is funded through life insurance contracts on the participating officers, though the plan does not require formal funding. As of December 31, 2014 and 2013, the life insurance contracts related to the SERP had an aggregate cash surrender value of $31.4 million and $45.5 million, respectively. As of December 31, 2014 and 2013, the vested benefit obligation under the SERP was less than the cash surrender value of the life insurance contracts respectively.

STOCKHOLDERS_EQUITY_AND_EARNIN

STOCKHOLDERS' EQUITY AND EARNINGS PER SHARE	12 Months Ended
	Dec. 31, 2014
STOCKHOLDERS' EQUITY AND EARNINGS PER SHARE
STOCKHOLDERS' EQUITY AND EARNINGS PER SHARE	NOTE 18 — STOCKHOLDERS’ EQUITY AND EARNINGS PER SHARE
	Series A Preferred Stock Offering — In April 2008, the Company issued 200,000 shares of 8% Non-Cumulative Perpetual Convertible Preferred Stock, Series A (“Series A”), with a liquidation preference of $1,000 per share. The Company received $194.1 million of additional Tier 1 qualifying capital, after deducting stock issuance costs. On May 1, 2013, the Company exercised its mandatory conversion right related to all the outstanding shares of its Series A preferred stock. At the conversion date, the remaining 85,710 shares of outstanding Series A Preferred Stock were converted to 5,594,080 shares of common stock.
	MetroCorp Acquisition — On January 17, 2014, the Company completed the acquisition of MetroCorp. The final consideration included 5,583,093 shares of East West common stock, $89.4 million of cash, $2.4 million of additional cash to MetroCorp stock option holders and a MetroCorp warrant, fair valued at $8.8 million, assumed by the Company.  Prior to the acquisition, MetroCorp had an outstanding warrant to purchase 771,429 shares of its common stock.  At acquisition, the rights of the warrant holder were converted into the right to acquire 230,282 shares of East West’s common stock. The warrant has not been exercised as of December 31, 2014.
	Stock Repurchase Program — On January 23, 2013, the Company's Board of Directors authorized a stock repurchase program to buy back up to $200.0 million of the Company's common stock. During 2013, the Company completed the authorized repurchased program, repurchasing 8,026,807 shares at a weighted average price of $24.89 per share for a total cost of $200.0 million.
	On July 17, 2013, the Company’s Board of Directors authorized a stock repurchase program to buy back up to $100.0 million of the Company’s common stock. The Company did not repurchase any shares under this program during the years ended December 31, 2014 and 2013.
	On January 19, 2012, the Company’s Board of Directors authorized a stock repurchase program to buy back up to $200.0 million of the Company’s common stock. During 2012, the Company completed the authorized repurchase program, repurchasing 9,068,105 shares at a weighted average price of $22.02 per share and a total cost of $199.9 million.
	Quarterly Dividends — The Company paid quarterly dividends on its common stock of $0.18 per share for each quarter of 2014. In comparison, the Company paid quarterly dividends on its common stock of $0.15 and $0.10 per share for each quarter of 2013 and 2012. Total dividends amounting to $104.0 million, $83.3 million and $57.6 million were paid to the Company’s common stockholders during the years ended December 31, 2014, 2013 and 2012, respectively.
	The Company’s Board of Directors declared and paid quarterly preferred stock cash dividends of $20.00 per share on its Series A preferred stock in 2013 and 2012. Cash dividends totaling $3.4 million and $6.9 million were paid to the Company’s Series A preferred stock stockholders during the years ended December 31, 2013 and 2012. The Series A preferred stock were converted into common stock on May 1, 2013.
	Earnings Per Share (“EPS”) — Certain of the Company’s instruments containing rights to nonforfeitable dividends granted in stock-based payment transactions are considered participating securities prior to vesting and, therefore, have been included in the earnings allocations in computing basic and diluted EPS under the two-class method. Basic EPS was computed by dividing net income, net of income allocated to participating securities, by the weighted-average number of common shares outstanding during each period, net of treasury shares and including vested but unissued shares and share units. The computation of diluted EPS reflects the additional dilutive effect of common stock equivalents such as unvested stock awards and stock options.
	The following tables present earnings per share calculations for the years ended December 31, 2014, 2013 and 2012:
			Year Ended December 31, 2014
			Net Income				Number of Shares			Per Share Amounts
			(In thousands, except per share data)
	Net income		$	342,483
	Less:
	Preferred stock dividends		—
	Earnings allocated to participating securities		(502		)
	Basic EPS — income allocated to common stockholders		$	341,981			142,952			$	2.39
	Effect of dilutive securities:
	Stock options		—				67
	Restricted stock units		287				398
	Convertible preferred stock		—				—
	Warrants		—				146
	Diluted EPS — income allocated to common stockholders		$	342,268			143,563			$	2.38
			Year Ended December 31, 2013
			Net Income				Number of Shares			Per Share Amounts
			(In thousands, except per share data)
	Net income		$	295,045
	Less:
	Preferred stock dividends		(3,428		)
	Earnings allocated to participating securities		(1,692		)
	Basic EPS — income allocated to common stockholders		$	289,925			137,342			$	2.11
	Effect of dilutive securities:
	Stock options		—				71
	Restricted stock units		196				327
	Convertible preferred stock		3,428				1,834
	Diluted EPS — income allocated to common stockholders		$	293,549			139,574			$	2.1
			Year Ended December 31, 2012
			Net Income				Number of Shares			Per Share Amounts
			(In thousands, except per share data)
	Net income		$	281,650
	Less:
	Preferred stock dividends		(6,857		)
	Earnings allocated to participating securities		(3,279		)
	Basic EPS — income allocated to common stockholders		$	271,514			141,457			$	1.92
	Effect of dilutive securities:
	Stock options		—				29
	Restricted stock units		47				118
	Convertible preferred stock		6,857				5,571
	Diluted EPS — income allocated to common stockholders		$	278,418			147,175			$	1.89
	The following table presents the weighted-average stock options outstanding and restricted stock units for the years ended December 31, 2014, 2013, and 2012, respectively, that were anti-dilutive, and therefore not included in the computation of diluted EPS:
			Year Ended December 31,
			2014			2013			2012
			(In thousands)
	Stock options		20			177			340
	Restricted stock units		7			10			5
	Accumulated Other Comprehensive Income (Loss) — As of December 31, 2014, total accumulated other comprehensive income was $4.2 million which includes the following components: net unrealized gains on securities available for sale of $4.2 million and net unrealized losses on other investments of $61 thousand. As of December 31, 2013, total accumulated other comprehensive loss was $(30.5) million which includes the following components: net unrealized losses on securities available for sale of $(30.5) million and unrealized gains on other investments of $79 thousand. As of December 31, 2012, total accumulated other comprehensive income was $4.7 million which includes the following components: net unrealized gains on securities available for sale of $4.6 million, and unrealized gains on other investments of $26 thousand.
	The accumulated other comprehensive income (loss) balances were as follows:
			2014											2013									2012
	Year Ended December 31,		Investment				Other				Accumulative			Investment			Other			Accumulative			Investment			Other			Foreign Currency Translation Adjustments			Accumulative
			Securities				Investments				Other			Securities			Investments			Other			Securities			Investments						Other
			Available-for-Sale								Comprehensive			Available-for-Sale						Comprehensive			Available-for-Sale									Comprehensive
											(Loss) Income									Income (Loss)												(Loss) Income
														(In thousands)
Balance, beginning of the period		$	(30,538	)		$	79			$	(30,459	)	$	4,643		$	26		$	4,669		$	(34,848	)	$	8		$	900		$	(33,940	)
Net unrealized gains (losses) arising during period		41,008				(97		)		40,911			(28,169		)	336			(27,833		)	42,868			31			—			42,899
Less: reclassification adjustment for (gains) losses included in net income		(6,294		)		79				(6,215		)	(7,012		)	(283		)	(7,295		)	(439		)	(13		)	—			(452		)
Net unrealized gains (losses)		34,714				(18		)		34,696			(35,181		)	53			(35,128		)	42,429			18			—			42,447
Noncredit-related impairment loss on securities		—				—				—			—			—			—			(2,938		)	—			—			(2,938		)
Foreign currency translation adjustments		—				—				—			—			—			—			—			—			(900		)	(900		)
Balance, end of the period		$	4,176			$	61			$	4,237		$	(30,538	)	$	79		$	(30,459	)	$	4,643		$	26		$	—		$	4,669
The components of other comprehensive income (loss), reclassifications to net income by income statement line item and the related tax effects were as follows:
		2014											2013									2012
Year Ended December 31,		Before-Tax				Tax				Net-of-Tax			Before-Tax			Tax			Net-of-Tax			Before-Tax			Tax			Net-of-Tax
		Amount				Expense				Amount			Amount			Expense			Amount			Amount			Expense			Amount
						or Benefit										or Benefit									or Benefit
													(In thousands)
Unrealized gains (losses) on investment securities available-for-sale:
Net unrealized gains (losses) arising during period		$	70,704			$	(29,696	)		$	41,008		$	(48,567	)	$	20,398		$	(28,169	)	$	73,910		$	(31,042	)	$	42,868
Less: reclassification adjustment for gains included in net income (1)		(10,851		)		4,557				(6,294		)	(12,089		)	5,077			(7,012		)	(757		)	318			(439		)
Net unrealized gains (losses)		59,853				(25,139		)		34,714			(60,656		)	25,475			(35,181		)	73,153			(30,724		)	42,429
Noncredit-related impairment loss on securities		—				—				—			—			—			—			(5,066		)	2,128			(2,938		)
Foreign currency translation adjustments		—				—				—			—			—			—			(1,552		)	652			(900		)
Unrealized (losses) gains on other investments:
Net unrealized (losses) gains arising during period		(167		)		70				(97		)	579			(243		)	336			53			(22		)	31
Less: reclassification adjustment for losses (gains) included in income (2)		136				(57		)		79			(488		)	205			(283		)	(23		)	10			(13		)
Net unrealized (losses) gains		(31		)		13				(18		)	91			(38		)	53			30			(12		)	18
Other comprehensive income (loss)		$	59,822			$	(25,126	)		$	34,696		$	(60,565	)	$	25,437		$	(35,128	)	$	66,565		$	(27,956	)	$	38,609
-1	The pretax amount is reported in net gains on sales of investment securities in the consolidated statements of income.
-2	The pretax income is reported in dividend and other investment income in the consolidated statements of income.

REGULATORY_REQUIREMENTS

REGULATORY REQUIREMENTS	12 Months Ended
	Dec. 31, 2014
REGULATORY REQUIREMENTS
REGULATORY REQUIREMENTS	NOTE 19 — REGULATORY REQUIREMENTS
	Capital Adequacy — The Bank is a member bank of the Federal Reserve System and the Federal Reserve Bank is the Bank’s primary regulator. The Company and the Bank are subject to various regulatory capital requirements administered by the federal banking agencies. These requirements are based upon the 1988 capital accord (“Basel I”) of the Basel Committee on Banking Supervision. The Federal Deposit Insurance Corporation Improvement Act of 1991 requires that the federal regulatory agencies adopt regulations defining capital tiers for banks: well capitalized, adequately capitalized, undercapitalized, significantly undercapitalized and critically undercapitalized. Failure to meet minimum capital requirements can initiate certain mandatory actions by regulators that, if undertaken, could have a direct material effect on the Company’s consolidated financial statements. Under capital adequacy guidelines, the Company and the Bank must meet specific capital guidelines that involve quantitative measures of the Company and the Bank's assets, liabilities and certain off-balance sheet items as calculated under regulatory accounting practices. The capital amounts and classification are also subject to qualitative judgments by the regulators about components, risk weightings and other factors.
	As of December 31, 2014 and 2013, the Bank was categorized as well capitalized under the regulatory framework for prompt corrective action. To be categorized as well capitalized, the Bank must maintain specific Basel I total risk-based, Tier I risk-based, and Tier I leverage ratios as set forth in the table below. The Company believes that no changes in conditions or events have occurred since December 31, 2014, which would result in changes that would cause the Company or the Bank to fall below the well capitalized level.
	The following table presents the regulatory capital information of the Company and the Bank as of December 31, 2014 and 2013:
		Actual				For Capital				To Be Well Capitalized
						Adequacy Purposes				Under Prompt Corrective
										Action Provisions
		Amount		Ratio		Amount		Ratio		Amount		Ratio
						($ in thousands)
	As of December 31, 2014
	Total Capital (to Risk-Weighted Assets)
	Company	$	2,753,598	12.6	%	$	1,754,519	8	%	N/A		N/A
	East West Bank	$	2,590,174	11.8	%	$	1,750,006	8	%	$	2,187,508	10	%
	Tier I Capital (to Risk-Weighted Assets)
	Company	$	2,405,452	11	%	$	877,259	4	%	N/A		N/A
	East West Bank	$	2,316,615	10.6	%	$	875,003	4	%	$	1,312,505	6	%
	Tier I Capital (to Average Assets)
	Company	$	2,405,452	8.4	%	$	1,140,045	4	%	N/A		N/A
	East West Bank	$	2,316,615	8.2	%	$	1,136,734	4	%	$	1,420,917	5	%
	As of December 31, 2013
	Total Capital (to Risk-Weighted Assets)
	Company	$	2,395,109	13.5	%	$	1,416,203	8	%	N/A		N/A
	East West Bank	$	2,262,494	12.9	%	$	1,407,944	8	%	$	1,759,931	10	%
	Tier I Capital (to Risk-Weighted Assets)
	Company	$	2,102,476	11.9	%	$	708,102	4	%	N/A		N/A
	East West Bank	$	2,041,894	11.6	%	$	703,972	4	%	$	1,055,958	6	%
	Tier I Capital (to Average Assets)
	Company	$	2,102,476	8.6	%	$	976,596	4	%	N/A		N/A
	East West Bank	$	2,041,894	8.4	%	$	973,958	4	%	$	1,217,448	5	%
	Under the Dodd-Frank Act, bank holding companies with more than $15 billion in total consolidated assets are no longer able to include trust preferred securities as Tier I regulatory capital which commenced in 2013 with phase-out complete in 2016. As of December 31, 2014 and 2013, trust preferred securities comprised 3.1% and 4.4%, respectively, of the Company’s Basel I Tier I capital.
	In July 2013, the FRB published final rules (the “Basel III Capital Rules”) establishing a new comprehensive capital framework for U.S. banking organizations. The final rules apply to all depository institutions and top-tier bank holding companies with assets of $500 million or more. The Basel III Capital Rules are effective for the Company and the Bank on January 1, 2015 (subject to phase-in periods for certain of their components).
	Reserve Requirement — The Bank is required to maintain a percentage of its deposits as reserves at the Federal Reserve Bank. The daily average reserve requirement was approximately $325.7 million and $218.5 million as of December 31, 2014 and 2013, respectively.

SEGMENT_INFORMATION

SEGMENT INFORMATION	12 Months Ended
	Dec. 31, 2014
SEGMENT INFORMATION
SEGMENT INFORMATION	NOTE 20 — SEGMENT INFORMATION
	The Company utilizes an internal reporting system to measure the performance of various operating segments within the Bank and the Company. The Company has identified three operating segments for purposes of management reporting: 1) Retail Banking; 2) Commercial Banking; and 3) Other. These three business divisions meet the criteria of an operating segment: the segment engages in business activities from which it earns revenues and incurs expenses and whose operating results are regularly reviewed by the Company’s chief operating decision-maker to render decisions about resources to be allocated to the segment and assess its performance and for which discrete financial information is available. The acquisition of MetroCorp has been reflected in the three business operating segments, as applicable, as of December 31, 2014.
	The Retail Banking segment focuses primarily on retail operations through the Bank’s branch network. The Commercial Banking segment, which includes CRE, primarily generates commercial loans through the efforts of the commercial lending offices located in the Bank’s production offices. Furthermore, the Company’s Commercial Banking segment also offers a wide variety of international finance and trade services and products. The remaining centralized functions, including treasury activities and eliminations of inter-segment amounts, have been aggregated and included in the Other segment, which provides broad administrative support to the two core segments.
	The Company’s funds transfer pricing assumptions are intended to promote core deposit growth and to reflect the current risk profiles of various loan categories within the credit portfolio. Transfer pricing assumptions and methodologies are reviewed at least annually to ensure that the Company’s process is reflective of current market conditions. The transfer pricing process is formulated with the goal of incenting loan and deposit growth that is consistent with the Company’s overall growth objectives as well as to provide a reasonable and consistent basis for the measurement of the Company’s business segments and product net interest margins.
	The accounting policies of the segments are the same as those described in the summary of significant accounting policies. Operating segment results are based on the Company’s internal management reporting process, which reflects assignments and allocations of certain operating and administrative costs and the provision for loan losses. Net interest income is based on the Company’s internal funds transfer pricing system which assigns a cost of funds or a credit for funds to assets or liabilities based on their type, maturity or repricing characteristics. Noninterest income and noninterest expense, including depreciation and amortization, directly attributable to a segment are assigned to that business segment. Indirect costs, including overhead expense, are allocated to the segments based on several factors, including, but not limited to, full-time equivalent employees, loan volume and deposit volume. The provision for credit losses is allocated based on actual charge-offs for the period as well as average loan balances for each segment during the period. The Company evaluates overall performance based on profit or loss from operations before income taxes excluding nonrecurring gains and losses.
	Changes in the Company’s management structure or reporting methodologies may result in changes in the measurement of operating segment results. Results for prior periods are generally restated for comparability for changes in management structure or reporting methodologies unless it is not deemed practicable to do so.
	The following tables present the operating results and other key financial measures for the individual operating segments as of and for the years ended December 31, 2014, 2013, and 2012:
			Year Ended December 31, 2014
			Retail			Commercial			Other			Total
			Banking			Banking
			(In thousands)
	Interest and dividend income		$	378,445		$	715,075		$	60,178		$	1,153,698
	Charge for funds used		(94,162		)	(141,652		)	(47,570		)	(283,384		)
	Interest spread on funds used		284,283			573,423			12,608			870,314
	Interest expense		(48,020		)	(15,650		)	(49,150		)	(112,820		)
	Credit on funds provided		225,873			38,592			18,919			283,384
	Interest spread on funds provided		177,853			22,942			(30,231		)	170,564
	Net interest income (loss) before provision for loan losses		$	462,136		$	596,365		$	(17,623	)	$	1,040,878
	Provision for loan losses		$	14,979		$	34,179		$	—		$	49,158
	Depreciation, amortization and accretion (1)		$	14,376		$	(8,372	)	$	108,117		$	114,121
	Goodwill		$	357,207		$	112,226		$	—		$	469,433
	Income before provision for income taxes		$	166,637		$	276,601		$	(27,783	)	$	415,455
	Assets		$	7,621,808		$	15,595,862		$	5,520,379		$	28,738,049
			Year Ended December 31, 2013
			Retail			Commercial			Other			Total
			Banking			Banking
			(In thousands)
	Interest and dividend income		$	374,818		$	627,118		$	66,749		$	1,068,685
	Charge for funds used		(86,552		)	(116,161		)	(18,244		)	(220,957		)
	Interest spread on funds used		288,266			510,957			48,505			847,728
	Interest expense		(47,287		)	(15,185		)	(50,020		)	(112,492		)
	Credit on funds provided		173,194			29,262			18,501			220,957
	Interest spread on funds provided		125,907			14,077			(31,519		)	108,465
	Net interest income before provision for loan losses		$	414,173		$	525,034		$	16,986		$	956,193
	Provision for loan losses		$	10,911		$	11,453		$	—		$	22,364
	Depreciation, amortization and accretion (1)		$	19,865		$	8,120		$	69,125		$	97,110
	Goodwill		$	320,566		$	16,872		$	—		$	337,438
	Income before provision for income taxes		$	123,876		$	272,369		$	29,605		$	425,850
	Assets		$	7,820,191		$	11,545,405		$	5,364,472		$	24,730,068
			Year Ended December 31, 2012
			Retail			Commercial			Other			Total
			Banking			Banking
			(In thousands)
	Interest and dividend income		$	356,244		$	617,041		$	77,810		$	1,051,095
	Charge for funds used		(85,811		)	(118,688		)	44,407			(160,092		)
	Interest spread on funds used		270,433			498,353			122,217			891,003
	Interest expense		(57,401		)	(23,226		)	(51,541		)	(132,168		)
	Credit on funds provided		130,713			13,138			16,241			160,092
	Interest spread on funds provided		73,312			(10,088		)	(35,300		)	27,924
	Net interest income before provision for loan losses		$	343,745		$	488,265		$	86,917		$	918,927
	Provision for loan losses		$	28,729		$	36,455		$	—		$	65,184
	Depreciation, amortization and accretion (1)		$	12,869		$	(13,277	)	$	44,159		$	43,751
	Goodwill		$	320,566		$	16,872		$	—		$	337,438
	Income before provision for income taxes		$	74,836		$	266,168		$	84,588		$	425,592
	Assets		$	6,552,217		$	10,421,160		$	5,562,733		$	22,536,110
	-1	Includes amortization and accretion related to the FDIC indemnification asset.

PARENT_COMPANY_CONDENSED_FINAN

PARENT COMPANY CONDENSED FINANCIAL STATEMENTS	12 Months Ended
	Dec. 31, 2014
PARENT COMPANY CONDENSED FINANCIAL STATEMENTS
PARENT COMPANY CONDENSED FINANCIAL STATEMENTS	NOTE 21 — PARENT COMPANY CONDENSED FINANCIAL STATEMENTS
	The financial information of East West Bancorp, Inc. as of December 31, 2014 and 2013 and for the years ended December 31, 2014, 2013 and 2012 are as follows:
	CONDENSED BALANCE SHEETS
		December 31,
		2014			2013
		(In thousands)
	ASSETS
	Cash and cash equivalents	$	211,053		$	79,934
	Investment securities available-for-sale, at fair value	8,370			69,796
	Investment in subsidiaries	2,841,684			2,400,937
	Other investments	41,054			21,371
	Other assets	22,474			37,037
	TOTAL	$	3,124,635		$	2,609,075
	LIABILITIES AND STOCKHOLDERS’ EQUITY
	Long-term debt	$	225,848		$	226,868
	Other liabilities	48,219			17,982
	Total liabilities	274,067			244,850
	STOCKHOLDERS’ EQUITY
	Common stock, $0.001 par value, 200,000,000 shares authorized; 163,772,218 and 163,098,008 shares issued in 2014 and 2013, respectively; 143,582,229 and 137,630,896 shares outstanding in 2014 and 2013, respectively.	164			163
	Additional paid in capital	1,677,767			1,571,670
	Retained earnings	1,598,598			1,360,130
	Treasury stock, at cost — 20,189,989 shares in 2014 and 25,467,112 shares in 2013	(430,198		)	(537,279		)
	Accumulated other comprehensive income (loss), net of tax	4,237			(30,459		)
	Total stockholders’ equity	2,850,568			2,364,225
	TOTAL	$	3,124,635		$	2,609,075
	CONDENSED STATEMENTS OF INCOME
		Year Ended December 31,
		2014			2013			2012
		(In thousands)
	Dividends from subsidiaries	$	111,701		$	319,085		$	324,094
	Other income	7,414			821			2
	Total income	119,115			319,906			324,096
	Interest expense	4,823			3,436			3,092
	Compensation and net occupancy reimbursement to subsidiary	4,039			3,662			2,573
	Other expense	50,280			12,677			1,309
	Total expense	59,142			19,775			6,974
	Income before income taxes and equity in undistributed income of subsidiaries	59,973			300,131			317,122
	Income tax benefit	80,674			22,885			2,892
	Equity in undistributed income (loss) of subsidiaries	201,836			(27,971		)	(38,364		)
	Net income	$	342,483		$	295,045		$	281,650
	CONDENSED STATEMENTS OF CASH FLOWS
		Year Ended December 31,
		2014			2013			2012
		(In thousands)
	CASH FLOWS FROM OPERATING ACTIVITIES
	Net income	$	342,483		$	295,045		$	281,650
	Adjustments to reconcile net income to net cash provided by operating activities:
	Equity in undistributed income of subsidiaries	(314,225		)	(291,659		)	(285,636		)
	Depreciation and amortization	46,365			8,806			445
	Gains on sales of investment securities and other investments	(4,357		)	(161		)	—
	Tax benefit from stock compensation plans, net	(6,513		)	(5,522		)	(462		)
	Net change in other assets	186,232			293,153			322,361
	Net change in other liabilities	150			(41		)	(25		)
	Net cash provided by operating activities	250,135			299,621			318,333
	CASH FLOWS FROM INVESTING ACTIVITIES
	Purchases of:
	Investment securities available-for-sale	(9,000		)	(69,986		)	—
	Equity investments	(53,071		)	(12,970		)	(234		)
	Proceeds from sale of:
	Investment securities available-for-sale	74,002			—			—
	Net cash provided by (used in) investing activities	11,931			(82,956		)	(234		)
	CASH FLOWS FROM FINANCING ACTIVITIES
	Payments for:
	Repayment of long-term debt	(30,310		)	(10,310		)	—
Repurchase of vested shares due to employee tax liability	(10,326		)	(13,833		)	(3,012		)
Cash dividends on preferred stock	—			(3,428		)	(6,857		)
Cash dividends on common stock	(103,618		)	(82,862		)	(57,361		)
Repurchase of shares of treasury stock pursuant to the Stock Repurchase Plan	—			(199,992		)	(199,950		)
Proceeds from:
Increase in long-term borrowings	—			100,000			—
Issuance of common stock pursuant to various stock plans and agreements	6,794			3,683			3,821
Tax benefit from stock compensation plans, net	6,513			5,522			462
Net cash used in financing activities	(130,947		)	(201,220		)	(262,897		)
Net increase in cash and cash equivalents	131,119			15,445			55,202
Cash and cash equivalents, beginning of year	79,934			64,489			9,287
Cash and cash equivalents, end of year	$	211,053		$	79,934		$	64,489
Supplemental Cash Flow Information:
Cash paid during the year for:
Interest	$	4,462		$	3,292		$	3,112
Noncash financing activities:
Conversion of preferred stock to common stock	$	—		$	83,027		$	—
Issuance of common stock related to acquisition	$	190,830		$	—		$	—

QUARTERLY_FINANCIAL_INFORMATIO

QUARTERLY FINANCIAL INFORMATION (unaudited)	12 Months Ended
	Dec. 31, 2014
QUARTERLY FINANCIAL INFORMATION (unaudited)
QUARTERLY FINANCIAL INFORMATION (unaudited)	NOTE 22 — QUARTERLY FINANCIAL INFORMATION (unaudited)
		Quarters Ended
		December 31,			September 30,			June 30,			March 31,
		(In thousands, except per share data)
	2014
	Interest and dividend income	$	287,135		$	285,948		$	294,442		$	286,173
	Interest expense	27,647			28,974			27,992			28,207
	Net interest income before provision for loan losses	259,488			256,974			266,450			257,966
	Provision for loan losses on non-covered loans	19,671			7,556			8,944			7,954
	(Reversal of) provision for loan losses on covered loans	(671		)	7,669			(944		)	(1,021		)
	Net interest income after provision for loan losses	240,488			241,749			258,450			251,033
	Noninterest income (loss)	7,805			10,342			(14,945		)	(14,916		)
	Noninterest expense	135,246			176,979			127,899			124,427
	Income before taxes	113,047			75,112			115,606			111,690
	Income tax provision (benefit)	20,049			(13,644		)	31,618			34,949
	Net income	$	92,998		$	88,756		$	83,988		$	76,741
	Basic earnings per share	$	0.65		$	0.62		$	0.59		$	0.54
	Diluted earnings per share	$	0.65		$	0.62		$	0.58		$	0.54
	2013
	Interest and dividend income	$	293,203		$	281,706		$	255,353		$	238,423
	Interest expense	28,195			27,456			27,709			29,132
	Net interest income before provision for loan losses	265,008			254,250			227,644			209,291
	Provision for (reversal of) loan losses on non-covered loans	6,286			4,535			8,277			(762		)
	(Reversal of) provision for loan losses on covered loans	(820		)	(964		)	723			5,089
	Net interest income after provision for loan losses	259,542			250,679			218,644			204,964
	Noninterest loss	(36,594		)	(41,421		)	(12,354		)	(2,099		)
	Noninterest expense	124,384			100,352			94,420			96,355
	Income before taxes	98,564			108,906			111,870			106,510
	Income tax provision	22,782			35,749			37,855			34,419
	Net income	75,782			73,157			74,015			72,091
	Preferred stock dividends	—			—			1,714			1,714
	Net income available to common stockholders	$	75,782		$	73,157		$	72,301		$	70,377
	Basic earnings per share	$	0.55		$	0.53		$	0.52		$	0.51
	Diluted earnings per share	$	0.55		$	0.53		$	0.52		$	0.5

SUBSEQUENT_EVENTS

SUBSEQUENT EVENTS	12 Months Ended
	Dec. 31, 2014
SUBSEQUENT EVENTS
SUBSEQUENT EVENTS	NOTE 23 — SUBSEQUENT EVENTS
	Dividend Payout
	On January 21, 2015, the East West Board of Directors declared first quarter 2015 dividends on the Company’s common stock. The common stock dividend of $0.20 per share is payable on or about February 17, 2015 to stockholders of record on February 2, 2015.
	The Company has evaluated the effect of events that have occurred subsequent to December 31, 2014, and there have been no material events that would require recognition in the 2014 consolidated financial statements or disclosure in the notes to the consolidated financial statements.

SUMMARY_OF_OPERATIONS_AND_SIGN1

SUMMARY OF OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 31, 2014
SUMMARY OF OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES
Basis of Presentation	Basis of Presentation — The consolidated financial statements are prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and general practices within the banking industry. The following is a summary of significant principles used in the preparation of the accompanying consolidated financial statements. To prepare the consolidated financial statements in conformity with GAAP, management must make estimates based on conditions that affect the reported amounts of assets and liabilities as of the date of the consolidated financial statements and income and expenses during the reporting period and the related disclosures. Actual results could differ from those estimates.
Principles of Consolidation	Principles of Consolidation — The consolidated financial statements include the accounts of East West Bancorp, Inc., and its wholly owned subsidiaries, East West Bank and East West Insurance Services, Inc. Intercompany transactions and accounts have been eliminated in consolidation. East West also has six wholly owned subsidiaries that are statutory business trusts (the “Trusts”). In accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 810, the Trusts are not consolidated into the accounts of East West Bancorp, Inc.
Cash and Cash Equivalents	Cash and Cash Equivalents — Cash and cash equivalents include cash on hand, cash items in transit, cash due from other financial institutions, money-market funds, and other short-term investments with original maturities up to 90 days. Short-term investments included in cash and cash equivalents are short-term bank placements and short-term securities purchased under resale agreements, recorded at cost, which approximates market.
Short-term Investments	Short-term Investments — Short-term investments include interest-bearing deposits in other banks and other short-term investments with original maturities greater than 90 days and less than one year.
Securities Purchased Under Resale Agreements and Sold Under Agreements to Repurchase	Securities Purchased Under Resale Agreements and Sold Under Agreements to Repurchase — The Company’s securities purchased under resale agreements (“resale agreements”) and securities sold under agreements to repurchase (“repurchase agreements”) are transacted under legally enforceable master repurchase agreements that give the Company, in the event of default by the counterparty, the right to liquidate securities held and to offset receivables and payables with the same counterparty. The Company nets repurchase and resale transactions with the same counterparty on the consolidated balance sheet where it has a legally enforceable master netting agreement and when the transactions are eligible for netting under ASC 210-20-45, Balance Sheet—Offsetting. The counterparties to these agreements are nationally recognized financial institutions that meet credit eligibility criteria. Collateral pledged consists of securities that are not recognized on the consolidated balance sheets. Collateral accepted includes securities that are not recognized on the consolidated balance sheets against the related collateralized liability. Collateral accepted or pledged in resale and repurchase agreements with other financial institutions also may be sold or re-pledged by the secured party, but is usually delivered to and held by third party trustees. The Company enters into resale agreements with terms that range from one day to several years. Resale agreements that are short-term in nature, or have terms of up to 90 days, are included in cash and cash equivalents.
Investment Securities Available-for-Sale	Investment Securities Available-for-Sale — The Company holds debt securities and marketable equity securities in its investment portfolio, classified as available-for-sale investments and reported at fair value. Unrealized gains and losses, after applicable income taxes, are reported in accumulated other comprehensive income.
	Amortization of premiums and accretion of discounts on investment securities are recorded as yield adjustments on such securities using the effective interest method. The specific identification method is used for purposes of determining cost in computing realized gains and losses on investment securities sold.
	Available-for-sale debt and marketable equity securities in unrealized loss positions are analyzed as part of the Company’s ongoing assessment of other-than-temporary impairment (“OTTI”). In determining whether an impairment is other than temporary, the Company considers the severity and duration of the decline in fair value, the length of time expected for recovery, the financial condition of the issuer, changes in the securities’ ratings and other qualitative factors, as well as whether the Company either plans to sell the security or it is more-likely-than-not that it will be required to sell the security before recovery of the amortized cost. If the impairment of the available-for-sale debt security is credit-related, an OTTI loss is recorded in earnings. For available-for-sale debt securities, the non-credit-related impairment loss is recognized in accumulated other comprehensive income. If the Company intends to sell an available-for-sale debt security or believes it will more-likely-than-not be required to sell a security, the Company records the full amount of the impairment loss as an OTTI loss. Available-for-sale marketable equity securities are carried at fair value with net unrealized gains and losses included in accumulated other comprehensive income on an after-tax basis. If there is an other-than-temporary decline in the fair value of any individual available-for-sale marketable equity security, the cost basis is reduced and the Company reclassifies the associated net unrealized loss out of accumulated other comprehensive income with a corresponding charge to the consolidated income statement.
Loans Held for Sale	Loans Held for Sale — Loans held for sale are mainly comprised of student loans carried at the lower of cost or fair value using the aggregate method. Origination fees on loans held for sale, net of certain costs of processing and closing the loans, are deferred until the time of sale and are included in the computation of the gain or loss from the sale of the related loans. A valuation allowance is established if the fair value of such loans is lower than their cost, with a corresponding charge to noninterest income.
Loans Receivable	Loans Receivable — Loans receivable that the Company has the intent and ability to hold for the foreseeable future, or until maturity, are stated at their outstanding principal, reduced by an allowance for loan losses and net of deferred loan fees or costs on originated loans and unamortized premiums or discounts on purchased loans. Nonrefundable fees and direct costs associated with the origination or purchase of loans are deferred and netted against outstanding loan balances. The deferred net loan fees and costs are recognized in interest income as an adjustment to yield over the loan term using the effective interest method. Discounts or premiums on purchased loans are accreted or amortized to interest income using the effective interest method over the remaining period to contractual maturity adjusted for anticipated prepayments. Interest on loans is calculated using the simple‑interest method on daily balances of the principal amounts outstanding. Accrual of interest is discontinued on a loan when management believes, after considering economic and business conditions and collection efforts, that the borrower’s financial condition is such that full collection of principal or interest becomes uncertain, regardless of the length of past due status. Generally, loans are placed on nonaccrual status when they become 90 days past due. When interest accrual is discontinued, all unpaid accrued interest recognized in interest income is reversed. Interest payments received on nonaccrual loans are reflected as a reduction of principal and not as interest income. A loan is returned to accrual status when the borrower has demonstrated a satisfactory payment trend subject to management’s assessment of the borrower’s ability to repay the loan.
Allowance for Loan Losses	Allowance for Loan Losses — The allowance for loan losses is established as management’s estimate of probable losses inherent in the loan portfolio. The allowance is increased by the provision for loan losses and decreased by charge-offs when management believes the uncollectability of a loan is confirmed. Subsequent recoveries, if any, are credited to the allowance. The allowance for loan losses is evaluated on a regular basis by management and is based on management’s periodic review of the collectability of the loans in light of historical experience, the nature and volume of the loan portfolio, adverse situations that may affect the borrower’s ability to repay, the estimated value of any underlying collateral and prevailing economic conditions. This evaluation is inherently subjective as it requires estimates that are susceptible to revision as more information becomes available. Additionally, non-classified loans are also considered in the allowance for loan losses calculation and are factored in based on the historical loss experience adjusted for various qualitative factors.
	A loan is considered impaired when, based on current information and events, it is probable that the Company will be unable to collect all scheduled payments of principal or interest due according to the contractual terms of the loan agreement. Factors considered by management in determining and measuring loan impairment include payment status, collateral value, and the probability of collecting scheduled principal and interest payments when due. Loans that experience insignificant payment delays and payment shortfalls generally are not classified as impaired. Management determines the significance of payment delays and payment shortfalls on a case-by-case basis, taking into consideration all of the circumstances surrounding the loan and the borrower, including the length of delay, the reasons for the delay, the borrower’s prior payment record and the amount of the shortfall in relation to the principal and interest owed. Impairment is measured on a loan-by-loan basis for residential, CRE, and commercial and industrial (“C&I”) loans based on the loan’s observable market price or the fair value of the collateral if the loan is collateral dependent, less costs to sell. If the measure of the impaired loan is less than the recorded investment in the loan and the loan is classified as nonperforming and uncollectible, the deficiency is charged off against the allowance for loan losses. In general, consumer loans consist of homogeneous smaller balance loans and are collectively evaluated for impairment.
Troubled Debt Restructurings	Troubled Debt Restructurings — A loan is identified as a troubled debt restructuring (“TDR”) when a modification of the loan terms takes place where the borrower is determined to be experiencing financial difficulties the Company grants a concession to the borrower in the restructuring that it would not otherwise consider. The concessions may be granted in various forms, including a below-market change in the stated interest rate, reduction in loan balance or accrued interest, extension of the maturity date with a stated interest rate lower than the current market rate or note splits with principal forgiveness. A restructuring executed at an interest rate that is at market interest rates is not considered as a TDR. All TDRs are reviewed for impairment on a quarterly basis. For modifications where the Company forgives principal, the entire amount of such principal forgiveness is immediately charged off. Generally, a nonaccrual loan that is restructured would remain on nonaccrual status for a period of six months to demonstrate that the borrower can perform under the restructured terms. However, the borrower’s performance prior to the restructuring, or other significant events at the time of restructuring may be considered in assessing whether the borrower can meet the new terms and may result in the loan remaining on non-accrual status or being returned to accrual status after a shorter performance period. If the borrower’s performance under the new terms is not reasonably assured, the loan remains classified as a nonaccrual loan. Loans classified as TDRs are reported as impaired loans.
Purchased Credit Impaired Loans	Purchased Credit Impaired Loans — Acquired loans, in accordance with ASC 805, Business Combinations, are recorded at fair value as of acquisition date. Loans purchased with evidence of credit deterioration since origination, purchased credit impaired (“PCI”) loans, for which it is probable that all contractually required payments will not be collected are accounted for under ASC 310-30, Receivables—Loans and Debt Securities Acquired with Deteriorated Credit Quality.
	Under ASC 310-30, loans are recorded at fair value at acquisition date, factoring in credit losses expected to be incurred over the life of the loan. Accordingly, an allowance for loan losses is not carried over or recorded as of the acquisition date. In situations where loans have similar risk characteristics, loans are aggregated into pools to estimate cash flows under ASC 310-30. A pool is accounted for as a single asset with a single interest rate, cumulative loss rate and cash flow expectation.
	The cash flows expected over the life of the loan or pool are estimated using an internal cash flow model that projects cash flows and calculates the carrying value of the loan or pool, book yield, effective interest income and impairment, if any, based on loan or pool level events, respectively. Assumptions as to default rates, loss severity, loss curves and prepayment speeds are utilized to calculate the expected cash flows.
	At acquisition, the excess of the cash flows expected to be collected over the recorded investment is considered to be the accretable yield and is recognized as interest income over the life of the loan or pool. The excess of the contractual cash flows over the cash flows expected to be collected is considered to be the nonaccretable difference. Subsequent to the acquisition date, any increases in expected cash flows over those expected at purchase date in excess of fair value that are significant and probable are adjusted through the accretable yield on a prospective basis. Any subsequent decreases in expected cash flows over those expected at purchase date that are probable are recognized by recording an allowance for loan losses. Any disposals of loans, including sales of loans, payments in full or foreclosures result in the removal of the loan from the ASC 310-30 portfolio at the carrying amount.
Covered Loans	Covered Loans — Loans acquired in an Federal Deposit Insurance Corporation (“FDIC”)-assisted acquisition that are subject to FDIC shared-loss agreements (“shared-loss agreements”) are referred to as covered loans. Covered loans are reported exclusive of the expected cash flow reimbursements expected to be collected from the FDIC. All covered loans are accounted for under ASC 805 and ASC 310-30.
FDIC Indemnification Asset/(Payable to FDIC, net)	FDIC Indemnification Asset/Payable to FDIC, net — In conjunction with the FDIC-assisted acquisitions of Washington First International Bank (“WFIB”) and United Commercial Bank (“UCB”), the Bank entered into shared-loss agreements with the FDIC related to covered loans and covered other real estate owned. The FDIC indemnification asset is initially recorded at fair value, based on the discounted value of expected future cash flows under the shared-loss agreement. The Company has elected to account for amounts receivable under the shared-loss agreements as an indemnification asset in accordance with ASC 805. The difference between the present value and the undiscounted cash flows the Company expects to collect from the FDIC is accreted into noninterest income over the life of the FDIC indemnification asset. The FDIC indemnification asset is reviewed on a quarterly basis and adjusted for any changes in expected cash flows based on recent performance and expectations for future performance of the covered portfolio. Any increases in cash flow of the covered loans over those expected will reduce the FDIC indemnification asset and any decreases in cash flow of the covered loans over those expected will increase the FDIC indemnification asset. Over the life of the FDIC indemnification asset, increases and decreases are recorded as adjustments to noninterest income. Due to continued payoffs and improved credit performance of the covered loan portfolio as compared to the Company's original estimates, the expected reimbursement from the FDIC under the shared-loss agreements has decreased and a payable to FDIC, net has been recorded. Additionally, the FDIC proportionately shares recoveries recognized on previously charged off covered loans.
Other Real Estate Owned	Other Real Estate Owned — Other real estate owned (“OREO”) represents properties acquired through foreclosure or through full or partial satisfaction of loans, is considered held for sale, and is recorded at the lower of cost or estimated fair value at the time of foreclosure. Loan balances in excess of the fair value of the real estate acquired at the date of foreclosure are charged against the allowance for loan losses. After foreclosure, the real estate is carried at the lower of carrying value or fair value less costs to sell. Subsequent declines in the fair value of OREO below the carrying value are recorded through the use of a valuation allowance by charges to noninterest expense. Any subsequent operating expenses or income of such properties are also charged to noninterest expense. If the OREO is sold within three months of foreclosure, the Company substitutes the value received in the sale (net of costs to sell) for the fair value (less costs to sell). Any adjustment made to the loss originally recognized at the time of foreclosure is then charged against or credited to the allowance for loan losses, if deemed material. Otherwise, any declines in value, after foreclosure, are recorded in noninterest expense as gains or losses from the sale or disposition of the real estate. Gain recognition upon disposition of a property is dependent on the sale having met certain criteria relating to the buyer’s initial investment in the property sold.
Covered Other Real Estate Owned	Covered OREO — All OREO acquired in an FDIC-assisted acquisition that are subject to a FDIC shared-loss agreement are referred to as covered OREO. Covered OREO is reported exclusive of the expected cash flow reimbursements the Company expects to collect from the FDIC. Upon transferring covered loan collateral to covered OREO status, acquisition date fair value discounts on the related loan are also transferred to covered OREO. Fair value adjustments on covered OREO result in a reduction of the covered OREO carrying amount through expense and a corresponding increase of the FDIC reimbursement for 80% of the adjustment resulting in income. The net of that expense and income is the non-reimbursed portion or 20% of the estimated loss to the Bank which is the net amount charged against earnings.
Investment in Affordable Housing Partnerships and Other Tax Credit Investments	Investment in Affordable Housing Partnerships and Other Tax Credit Investments — The Company records its investments in affordable housing partnerships and other tax credit investments using either the equity method or cost method of accounting. Investments that are recorded using the cost method, are being amortized over the life of the related tax credits. The tax credits are recognized on the consolidated financial statements to the extent they are utilized on the Company’s income tax returns. The investments are reviewed for impairment on an annual basis or on an interim basis if an event occurs that would trigger potential impairment.
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets — The Company has goodwill, which represents the excess of the purchase price over the fair value of net assets acquired, as a result of various past acquisitions. Goodwill is not amortized and is reviewed for impairment on an annual basis or on an interim basis if an event occurs or circumstances change that would reduce the fair value of a reporting unit below its carrying value. Premiums on deposits, which represent the intangible value of depositor relationships resulting from deposit liabilities assumed in acquisitions, are amortized over the projected useful lives of the deposits, which is typically 7 to 15 years. Core deposit intangibles are reviewed for impairment whenever events or changes in circumstances indicate that the carrying value may not be recoverable. Impairment on goodwill and premiums on deposits is recognized by writing down the asset to the extent that the carrying value exceeds the estimated fair value.
Investment in Federal Home Loan Bank Stock	Investment in FHLB Stock — As a member of the FHLB of San Francisco, the Bank is required to own common stock in the FHLB of San Francisco based upon the Company’s balance of residential mortgage loans and outstanding FHLB advances. As a result of the acquisition of WFIB in 2010, the Bank also owns common stock in the FHLB of Seattle. FHLB stock is carried at cost and may be sold back to the FHLB at its carrying value. Cash dividends are accrued and reported as dividend income.
Investment in Federal Reserve Bank Stock	Investment in Federal Reserve Bank Stock — As a member of the Federal Reserve Bank of San Francisco, the Bank is required to maintain stock in the Federal Reserve Bank of San Francisco based on a specified ratio relative to our capital. Federal Reserve Bank stock is carried at cost and may be sold back to the Federal Reserve Bank at its carrying value. Cash dividends are accrued and reported as dividend income.
Premises and Equipment	Premises and Equipment — The Company’s premises and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation and amortization are computed based on the straight-line method over the estimated useful lives of the various classes of assets. The ranges of useful lives for the principal classes of assets are as follows:
	Buildings and building improvements	25 years
	Furniture, fixtures and equipment	3 to 7 years
	Leasehold improvements	Term of lease or useful life, whichever is shorter
	The Company reviews its long-lived assets for impairment annually or when events or circumstances indicate that the carrying amount of these assets may not be recoverable. An asset is considered impaired when the expected undiscounted cash flows over the remaining useful life is less than the net book value. When impairment is indicated for an asset, the amount of impairment loss is the excess of the net book value over its fair value.
Long-Term Debt	Long-Term Debt — Long-term debt consists of junior subordinated debt and other long-term debt. The Company has six statutory business trusts whereby the Company is the owner of all the beneficial interests represented by the common securities of the Trusts, and third parties hold the fixed and variable rate capital securities of the Trusts. The purpose of issuing the capital securities was to provide the Company with a cost-effective means of obtaining Tier I capital for regulatory reporting purposes. However, these securities are being phased out of the Tier I capital, a process that commenced in 2013 with phase-out complete by 2016.
	The Trusts are not consolidated by the Company. Junior subordinated debt represents liabilities of the Company to the Trusts and is included in long-term debt on the accompanying consolidated balance sheets.
Income Taxes	Income Taxes — Deferred income taxes are recognized for the tax consequences in future years of differences between the tax bases of assets and liabilities and their financial reporting amounts at each year-end, based on enacted tax laws and statutory tax rates applicable to the periods in which the differences are expected to affect taxable income.
	The Company examines its financial statements, its income tax provision, and its federal and state income tax returns and analyzes its tax positions, including permanent and temporary differences, as well as the major components of income and expense to determine whether a tax benefit is more likely than not to be sustained upon examination by tax authorities. In the event a tax position is not more likely than not to be sustained by the tax authorities, a reserve is established by management. The Company recognizes interest and penalties related to tax positions as part of its provision for income taxes.
Stock-Based Compensation	Stock-Based Compensation — The Company issues stock-based compensation to certain employees, officers, and directors and accounts for stock options using the fair value method, which generally results in compensation expense recognition.
Earnings Per Share	Earnings Per Share — The Company applies the two-class method in computing earnings per share (“EPS”). The Company’s restricted stock, which receives dividends as declared, qualify as participating securities. Restricted stock units granted by the Company are not considered participating securities, as they do not have dividend distribution rights during the vesting period. Basic EPS is computed by dividing net income, net of income allocated to participating securities, by the weighted-average number of common shares outstanding during each period, net of treasury shares and including vested but unissued shares and share units. The computation of diluted EPS reflects the additional dilutive effect of common stock equivalents such as unvested stock awards and stock options.
Derivatives	Derivatives — As part of the asset and liability management strategy, the Company uses derivative financial instruments to mitigate exposure to interest rate and foreign currency risks. All derivative instruments, including certain derivative instruments embedded in other contracts, are recognized on the consolidated balance sheet at fair value with the changes in fair value reported in earnings.
	The Company’s interest rate swaps on certain certificates of deposit qualify for hedge accounting treatment under ASC 815, Derivatives and Hedging.  The Company documents its hedge relationships, including identification of the hedging instruments and the hedged items, as well as its risk management objectives and strategies for undertaking the hedge transaction at the time the derivative contract is executed. This includes designating the derivative contract as a “fair value hedge” which is a hedge of a recognized asset or liability.  All derivatives designated as fair value hedges are linked to specific hedged items or to groups of specific assets and liabilities on the balance sheet.  Both at inception and quarterly thereafter, the Company assesses whether the derivatives used in hedging transactions are highly effective in offsetting changes in the fair value of the hedged item. Retroactive effectiveness is also assessed as well as the continued expectation that the hedge will remain effective prospectively.  Any ineffective portion of the changes of fair value hedges is recognized immediately in interest expense in the consolidated statements of income.
	The Company discontinues hedge accounting prospectively when (i) a derivative is no longer highly effective in offsetting changes in the fair value, (ii) a derivative expires or is sold, terminated, or exercised, or (iii) the Company determines that designation of a derivative as a hedge is no longer appropriate. If a fair value hedge derivative instrument is terminated or the hedge designation removed, the previous adjustments to the carrying amount of the hedged liability would be subsequently accounted for in the same manner as other components of the carrying amount of that liability. For interest-bearing liabilities, such adjustments would be amortized into earnings over the remaining life of the respective liability.
	The Company also offers various derivative products to clients and enters into derivative transactions in due course. These transactions are not linked to specific Company assets or liabilities in the consolidated balance sheets or to forecasted transactions in a hedge relationship and, therefore, do not qualify for hedge accounting. The contracts are marked-to-market at the end of each reporting period with changes in fair value recorded in the consolidated statements of income.
Fair Value	Fair Value — Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date and, in many cases, requires management to make a number of significant judgments. Based on the observability of the inputs used in the valuation techniques, the Company classifies its assets and liabilities measured and disclosed at fair value in accordance with a three-level hierarchy (e.g., Level 1, Level 2 and Level 3) established under ASC 820, Fair Value Measurements. In determining the fair value of financial instruments, the Company uses market prices of the same or similar instruments whenever such prices are available. The Company does not use prices involving distressed sellers in determining fair value. If observable market prices are unavailable or impracticable to obtain, then fair value is estimated using modeling techniques such as discounted cash flow analysis. These modeling techniques incorporate management’s assessments regarding assumptions that market participants would use in pricing the asset or the liability, including assumptions about the risks inherent in a particular valuation technique and the risk of nonperformance.
Reclassifications	Reclassifications — Certain items in the consolidated financial statements and notes for the prior years have been reclassified to conform to the 2014 presentation.
ACCOUNTING PRONOUNCEMENTS	NEW ACCOUNTING PRONOUNCEMENTS ADOPTED
	In July 2013, the FASB issued ASU 2013-11, Income Taxes (Topic 740), Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists. ASU 2013-11 eliminates diversity in practice as it provides guidance on financial statement presentation of an unrecognized tax benefit when a net operating loss (“NOL”) carryforward, a similar tax loss, or a tax credit carryforward exists. The Company adopted this guidance in first quarter 2014 with prospective application to all unrecognized tax benefits that exist at the effective date. ASU 2013-11 did not have a material impact on the Company’s consolidated financial statements.
	RECENT ACCOUNTING PRONOUNCEMENTS
	In January 2014, the FASB issued ASU 2014-01, Investments—Equity Method and Joint Ventures (Topic 323): Accounting for Investments in Qualified Affordable Housing Projects. ASU 2014-10 permits reporting entities to make an accounting policy election to account for their investments in qualified affordable housing projects using the proportional amortization method if certain conditions are met. Under the proportional amortization method, an entity amortizes the initial cost of the investment in proportion to the tax credits and other tax benefits received and recognizes the net investment performance in the income statement as a component of income tax expense (benefit). ASU 2014-10 is effective for interim and annual periods beginning after December 15, 2014 and if elected, should be applied retrospectively to all periods presented. Early adoption is permitted. The Company is currently evaluating the impact on the Company’s consolidated financial statements.
	In January 2014, the FASB issued ASU 2014-04, Receivables—Troubled Debt Restructurings by Creditors (Subtopic 310-40): Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure. ASU 2014-04 clarifies when an in-substance repossession or foreclosure occurs that would require a transfer of mortgage loans collateralized by residential real estate properties to OREO. The standard permits the use of either a modified retrospective or prospective transition method.  ASU 2014-04 is effective for interim and annual periods beginning after December 15, 2014. Early adoption is permitted. The Company does not expect the adoption of this guidance to have a material effect on its consolidated financial statements.
	In May 2014, The FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606). The new guidance replaces existing revenue recognition guidance for contracts to provide goods or services to customers and amends  existing guidance related to recognition of gains and losses on the sale of certain nonfinancial assets such as real estate.  ASC 606 establishes a principles-based approach to recognizing revenue that applies to all contracts other than those covered by other authoritative GAAP guidance. Quantitative and qualitative disclosures regarding the nature, amount, timing and uncertainty of revenue and cash flows are also required.  ASC 606 is effective for interim and annual periods beginning after December 15, 2016 and is applied on either a modified retrospective or full retrospective basis. Early adoption is not permitted. The Company is currently evaluating the impact on its consolidated financial statements.

SUMMARY_OF_OPERATIONS_AND_SIGN2

SUMMARY OF OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES (Tables)	12 Months Ended
	Dec. 31, 2014
SUMMARY OF OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES
Schedule of useful lives for premises and equipment
	Buildings and building improvements	25 years
	Furniture, fixtures and equipment	3 to 7 years
	Leasehold improvements	Term of lease or useful life, whichever is shorter

BUSINESS_COMBINATION_Tables

BUSINESS COMBINATION (Tables)	12 Months Ended
	Dec. 31, 2014
BUSINESS COMBINATION
Schedule of Pro forma net interest income and noninterest loss and net income after tax
		Pro forma
		Year Ended December 31,
		2014		2013
		(In thousands)
	Net interest income and noninterest loss	$	1,028,796	$	934,207
	Net income after tax	$	338,730	$	299,625

FAIR_VALUE_MEASUREMENT_AND_FAI1

FAIR VALUE MEASUREMENT AND FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)	12 Months Ended
	Dec. 31, 2014
Quantitative information
Assets (Liabilities) Measured at Fair Value on a Recurring Basis
			Assets (Liabilities) Measured at Fair Value on a Recurring Basis as of
			31-Dec-14
			Fair Value Measurements December 31, 2014			Quoted Prices in			Significant			Significant
						Active Markets			Other			Unobservable
						for Identical			Observable			Inputs
						Assets			Inputs			(Level 3)
						(Level 1)			(Level 2)
			(In thousands)
	Investment securities available-for-sale:
	U.S. Treasury securities		$	873,435		$	873,435		$	—		$	—
	U.S. government agency and U.S. government sponsored enterprise debt securities		311,024			—			311,024			—
	U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities:
	Commercial mortgage-backed securities		141,420			—			141,420			—
	Residential mortgage-backed securities		791,088			—			791,088			—
	Municipal securities		250,448			—			250,448			—
	Other residential mortgage-backed securities:
	Investment grade		53,918			—			53,918			—
	Other commercial mortgage-backed securities:
	Investment grade		34,053			—			34,053			—
	Corporate debt securities:
	Investment grade		115,182			—			115,182			—
	Non-investment grade		14,681			—			8,153			6,528
	Other securities		41,116			32,105			9,011			—
	Total investment securities available-for-sale		$	2,626,365		$	905,540		$	1,714,297		$	6,528
	Derivative assets:
	Foreign exchange options		$	6,136		$	—		$	6,136		$	—
	Interest rate swaps and caps		$	41,534		$	—		$	41,534		$	—
	Foreign exchange contracts		$	8,123		$	—		$	8,123		$	—
	Derivative liabilities:
	Interest rate swaps on certificates of deposits		$	(9,922	)	$	—		$	(9,922	)	$	—
	Interest rate swaps and caps		$	(41,779	)	$	—		$	(41,779	)	$	—
	Foreign exchange contracts		$	(9,171	)	$	—		$	(9,171	)	$	—
	Embedded derivative liabilities		$	(3,392	)	$	—		$	—		$	(3,392	)
			Assets (Liabilities) Measured at Fair Value on a Recurring Basis as of
			31-Dec-13
			Fair Value Measurements December 31, 2013			Quoted Prices in			Significant			Significant
						Active Markets			Other			Unobservable
						for Identical			Observable			Inputs
						Assets			Inputs			(Level 3)
						(Level 1)			(Level 2)
			(In thousands)
	Investment securities available-for-sale:
	U.S. Treasury securities		$	491,632		$	491,632		$	—		$	—
	U.S. government agency and U.S. government sponsored enterprise debt securities		394,323			—			394,323			—
	U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities:
	Commercial mortgage-backed securities		178,870			—			178,870			—
	Residential mortgage-backed securities		885,237			—			885,237			—
	Municipal securities		280,979			—			280,979			—
	Other residential mortgage-backed securities:
	Investment grade		46,327			—			46,327			—
	Other commercial mortgage-backed securities:
	Investment grade		51,617			—			51,617			—
	Corporate debt securities:
	Investment grade		309,995			—			309,995			—
	Non-investment grade		15,101			—			8,730			6,371
	Other securities		79,716			—			79,716			—
	Total investment securities available-for-sale		$	2,733,797		$	491,632		$	2,235,794		$	6,371
	Derivative assets:
	Foreign exchange options		$	6,290		$	—		$	6,290		$	—
	Interest rate swaps and caps		$	28,078		$	—		$	28,078		$	—
	Foreign exchange contracts		$	6,181		$	—		$	6,181		$	—
	Derivative liabilities:
	Interest rate swaps on certificates of deposits		$	(16,906	)	$	—		$	(16,906	)	$	—
Interest rate swaps and caps		$	(26,352	)	$	—		$	(26,352	)	$	—
Foreign exchange contracts		$	(3,349	)	$	—		$	(3,349	)	$	—
Embedded derivative liabilities		$	(3,655	)	$	—		$	—		$	(3,655	)
Reconciliation of assets and liabilities measured at fair value using significant unobservable inputs
			Year Ended December 31,
			2014						2013						2012
			Corporate Debt			Embedded Derivative			Corporate Debt			Embedded Derivative			Corporate Debt			Embedded Derivative
			Securities:			Liabilities			Securities:			Liabilities			Securities:			Liabilities
			Non-Investment Grade						Non-Investment Grade						Non-Investment Grade
			(In thousands)
	Beginning balance		$	6,371		$	(3,655	)	$	4,800		$	(3,052	)	$	2,235		$	(2,634	)
	Total gains or (losses) for the period:
	Included in earnings(1)		802			263			—			(603		)	(99		)	(418		)
	Included in other comprehensive income (unrealized) (2)		2,326			—			1,653			—			2,711			—
	Purchases, issues, sales, settlements:
	Purchases		—			—			—			—			—			—
	Issues		—			—			—			—			—			—
	Sales		(2,595		)	—			—			—			—			—
	Settlements		(376		)	—			(82		)	—			(47		)	—
	Transfer from investment grade to non-investment grade		—			—			—			—			—			—
	Transfers in and/or out of Level 3		—			—			—			—			—			—
	Ending balance		$	6,528		$	(3,392	)	$	6,371		$	(3,655	)	$	4,800		$	(3,052	)
	Changes in unrealized losses included in earnings relating to assets and liabilities held at period-end		$	—		$	(263	)	$	—		$	603		$	99		$	418
	-1	Realized gains or losses of corporate debt securities and embedded derivative liabilities are included in net gains on sales of investment securities and other operating expense, respectively, in the consolidated statements of income.
	-2	Unrealized gains or losses on investment securities are reported in other comprehensive income (loss), net of tax, in the consolidated statements of comprehensive income.
Assets Measured at Fair Value on a Nonrecurring Basis
			Assets Measured at Fair Value on a Nonrecurring Basis as of
			31-Dec-14
			Fair Value			Quoted Prices in			Significant			Significant
			Measurements			Active Markets			Other			Unobservable
						for Identical			Observable			Inputs
						Assets			Inputs			(Level 3)
						(Level 1)			(Level 2)
			(In thousands)
	Non-covered impaired loans:
	CRE		$	26,089		$	—		$	—		$	26,089
	C&I		16,581			—			—			16,581
	Residential		25,034			—			—			25,034
	Consumer		107			—			—			107
	Total non-covered impaired loans		$	67,811		$	—		$	—		$	67,811
	Non-covered OREO		$	15,735		$	—		$	—		$	15,735
	Covered OREO		$	1,786		$	—		$	—		$	1,786
			Assets Measured at Fair Value on a Nonrecurring Basis as of
			31-Dec-13
			Fair Value			Quoted Prices in			Significant			Significant
			Measurements			Active Markets			Other			Unobservable
						for Identical			Observable			Inputs
						Assets			Inputs			(Level 3)
						(Level 1)			(Level 2)
			(In thousands)
	Non-covered impaired loans:
	CRE		$	29,559		$	—		$	—		$	29,559
	C&I		15,120			—			—			15,120
	Residential		12,791			—			—			12,791
	Consumer		281			—			—			281
	Total non-covered impaired loans		$	57,751		$	—		$	—		$	57,751
	Non-covered OREO		$	13,031		$	—		$	—		$	13,031
	Covered OREO		$	17,284		$	—		$	—		$	17,284
Summary of increase (decrease) in value of certain assets for which a nonrecurring fair value adjustment has been recognized
			Year Ended December 31,
			2014			2013			2012
			(In thousands)
	Non-covered impaired loans:
	CRE		$	2,196		$	(4,250	)	$	(8,405	)
	C&I		(9,169		)	(13,135		)	(14,540		)
	Residential		(61		)	(1,378		)	(4,803		)
	Consumer		(1		)	(112		)	(264		)
	Total non-covered impaired loans		$	(7,035	)	$	(18,875	)	$	(28,012	)
	Non-covered OREO		$	(1,573	)	$	(1,438	)	$	(5,122	)
	Covered OREO (1)		$	(1,027	)	$	(3,376	)	$	(11,183	)
	-1	Covered OREO results from the WFIB and UCB FDIC-assisted acquisitions for which the Company entered into shared-loss agreements with the FDIC whereby the FDIC will reimburse the Company for 80% of eligible losses. As such, the Company’s liability for losses is 20% of the $1.0 million in losses, or $205 thousand, and 20% of the $3.4 million in losses, or $675 thousand, and 20% of the $11.2 million in losses, or $2.2 million for the years ended December 31, 2014, 2013, and 2012, respectively.
Carrying amounts and fair values of financial instruments
			31-Dec-14
			Carrying			Level 1			Level 2			Level 3			Estimated
			Amount												Fair Value
			(In thousands)
	Financial assets:
	Cash and cash equivalents		$	1,039,885		$	1,039,885		$	—		$	—		$	1,039,885
	Short-term investments		$	338,714		$	—		$	338,714		$	—		$	338,714
	Securities purchased under resale agreements		$	1,225,000		$	—		$	1,191,060		$	—		$	1,191,060
	Loans held for sale		$	45,950		$	—		$	45,950		$	—		$	45,950
	Loans receivable, net		$	21,468,270		$	—		$	—		$	20,997,379		$	20,997,379
	Investment in Federal Home Loan Bank stock		$	31,239		$	—		$	31,239		$	—		$	31,239
	Investment in Federal Reserve Bank stock		$	54,451		$	—		$	54,451		$	—		$	54,451
	Accrued interest receivable		$	88,303		$	—		$	88,303		$	—		$	88,303
	Financial liabilities:
	Customer deposit accounts:
	Demand, savings and money market deposits		$	17,896,035		$	—		$	17,896,035		$	—		$	17,896,035
	Time deposits		$	6,112,739		$	—		$	—		$	6,095,217		$	6,095,217
	Federal Home Loan Bank advances		$	317,241		$	—		$	336,302		$	—		$	336,302
	Securities sold under repurchase agreements		$	795,000		$	—		$	870,434		$	—		$	870,434
	Accrued interest payable		$	11,303		$	—		$	11,303		$	—		$	11,303
	Long-term debt		$	225,848		$	—		$	205,777		$	—		$	205,777
			31-Dec-13
			Carrying			Level 1			Level 2			Level 3			Estimated
			Amount												Fair Value
			(In thousands)
	Financial assets:
	Cash and cash equivalents		$	895,820		$	895,820		$	—		$	—		$	895,820
	Short-term investments		$	257,473		$	—		$	257,473		$	—		$	257,473
	Securities purchased under resale agreements		$	1,300,000		$	—		$	1,279,406		$	—		$	1,279,406
	Loans held for sale		$	204,970		$	—		$	212,469		$	—		$	212,469
	Loans receivable, net		$	17,600,613		$	—		$	—		$	16,741,674		$	16,741,674
	Investment in Federal Home Loan Bank stock		$	62,330		$	—		$	62,330		$	—		$	62,330
	Investment in Federal Reserve Bank stock		$	48,333		$	—		$	48,333		$	—		$	48,333
	Accrued interest receivable		$	116,314		$	—		$	116,314		$	—		$	116,314
	Financial liabilities:
	Customer deposit accounts:
	Demand, savings and money market deposits		$	14,588,570		$	—		$	14,588,570		$	—		$	14,588,570
	Time deposits		$	5,824,348		$	—		$	—		$	5,791,659		$	5,791,659
	Federal Home Loan Bank advances		$	315,092		$	—		$	308,521		$	—		$	308,521
	Securities sold under repurchase agreements		$	995,000		$	—		$	1,134,774		$	—		$	1,134,774
	Accrued interest payable		$	11,178		$	—		$	11,178		$	—		$	11,178
	Long-term debt		$	226,868		$	—		$	184,415		$	—		$	184,415
Fair Value, Measurements, Recurring
Quantitative information
Schedule of quantitative information about significant unobservable inputs used in the valuation of assets and liabilities classified as Level 3
			Fair Value			Valuation Technique(s)		Unobservable Input(s)	Range of Inputs		Weighted
			Measurements								Average
			(Level 3)
			($ in thousands)
	31-Dec-14
	Investment securities available-for-sale:
	Corporate debt securities:
	Non-investment grade		$	6,528		Discounted cash flow		Constant prepayment rate	0% - 1%		0.73%
								Constant default rate	0.75% - 1.20%		0.87%
								Loss severity	85%		85%
								Discount margin	4.50% - 7.50%		6.94%
	Embedded derivative liabilities		$	(3,392	)	Discounted cash flow		Credit risk	0.115% - 0.142%		0.13%
	31-Dec-13
	Investment securities available-for-sale:
	Corporate debt securities:
	Non-investment grade		$	6,371		Discounted cash flow		Constant prepayment rate	0% - 1%		0.74%
								Constant default rate	0.75% - 1.20%		0.87%
								Loss severity	85%		85%
								Discount margin	6.50% - 11.50%		9.97%
	Embedded derivative liabilities		$	(3,655	)	Discounted cash flow		Credit risk	0.175% - 0.212%		0.20%
Fair Value, Measurements, Nonrecurring
Quantitative information
Schedule of quantitative information about significant unobservable inputs used in the valuation of assets and liabilities classified as Level 3
			Fair Value			Valuation		Unobservable	Range of Inputs		Weighted
			Measurements			Technique(s)		Input(s)			Average
			(Level 3)
			($ in thousands)
	31-Dec-14
	Non-covered impaired loans		$	11,499		Discounted cash flow		Discount rate	0% - 81%		49%
			56,312			Market comparables		Discount rate(1)	0% - 100%		4%
	Non-covered OREO		15,735			Appraisal		Selling cost	8%		8%
	Covered OREO		1,786			Appraisal		No Discount
	31-Dec-13
	Non-covered impaired loans		$	57,751		Market comparables		Discount rate(1)	0% - 100%		13%
	Non-covered OREO		13,031			Appraisal		Selling cost	8%		8%
	Covered OREO		17,284			Appraisal		No Discount
	(1)Discount rate is adjusted for factors such as liquidation cost of collateral and selling cost.

CASH_AND_CASH_EQUIVALENTS_AND_1

CASH AND CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS (Tables)	12 Months Ended
	Dec. 31, 2014
CASH AND CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS
Composition of cash and cash equivalents
		December 31,
		2014		2013
		(In thousands)
	Cash and amounts due from banks	$	944,118	$	693,387
	Cash equivalents:
	Money market funds	—		605
	Other short-term investments	95,767		201,828
	Total cash and cash equivalents	$	1,039,885	$	895,820

SECURITIES_REPURCHASED_UNDER_R

SECURITIES REPURCHASED UNDER RESALE AGREEMENTS AND SOLD UNDER REPURCHASE AGREEMENTS (Tables)	12 Months Ended
	Dec. 31, 2014
SECURITIES PURCHASED UNDER RESALE AGREEMENTS AND SOLD UNDER REPURCHASE AGREEMENTS
Schedule of resale agreements, repurchase agreements and the respective collateral received or pledged in the form of other financial instruments, which are generally marketable securities
			As of December 31, 2014
			(In thousands)
			Gross Amounts		Gross Amounts			Net Amounts of			Gross Amounts Not Offset on the
			of Recognized		Offset on the			Assets Presented			Consolidated Balance Sheets
			Assets		Consolidated			on the
					Balance Sheet			Consolidated
	Assets							Balance Sheet			Financial				Collateral				Net Amount
											Instruments				Received
	Resale agreements		$	1,425,000	$	(200,000	)	$	1,225,000		$	(425,000	)	(1)	$	(797,172	)	(2)	$	2,828
			Gross Amounts		Gross Amounts			Net Amounts of			Gross Amounts Not Offset on the
			of Recognized		Offset on the			Liabilities			Consolidated Balance Sheets
			Liabilities		Consolidated			Presented on the
					Balance Sheet			Consolidated
	Liabilities							Balance Sheet			Financial				Collateral				Net Amount
											Instruments				Posted
	Repurchase agreements		$	995,000	$	(200,000	)	$	795,000		$	(425,000	)	(1)	$	(370,000	)	(3)	$	—
			As of December 31, 2013
			(In thousands)
			Gross Amounts		Gross Amounts			Net Amounts of			Gross Amounts Not Offset on the
			of Recognized		Offset on the			Assets Presented			Consolidated Balance Sheets
			Assets		Consolidated			on the
					Balance Sheet			Consolidated
	Assets							Balance Sheet			Financial				Collateral				Net Amount
											Instruments				Received
	Resale agreements		$	1,400,000	$	—		$	1,400,000	(4)	$	(495,000	)	(1)	$	(905,000	)	(2)	$	—
			Gross Amounts		Gross Amounts			Net Amounts of			Gross Amounts Not Offset on the
			of Recognized		Offset on the			Liabilities			Consolidated Balance Sheets
			Liabilities		Consolidated			Presented on the
					Balance Sheet			Consolidated
	Liabilities							Balance Sheet			Financial				Collateral				Net Amount
											Instruments				Posted
	Repurchase agreements		$	995,000	$	—		$	995,000		$	(495,000	)	(1)	$	(500,000	)	(3)	$	—
	-1	Includes financial instruments subject to enforceable master netting arrangements that are not permitted to be offset under ASC 210-20-45 but would be eligible for offsetting to the extent an event of default has occurred.
	-2	Represents the fair value of securities the Company has received under resale agreements, limited for table presentation purposes to the amount of the recognized asset due from each counterparty.
	-3	Represents the fair value of securities the Company has pledged under repurchase agreements, limited for table presentation purposes to the amount of the recognized liability owed to each counterparty.
	-4	Of the $1.40 billion resale agreements as of December 31, 2013, $100.0 million was recorded in cash and cash equivalents and $1.30 billion was recorded in securities under resale agreements in the consolidated balance sheet.

INVESTMENT_SECURITIES_Tables

INVESTMENT SECURITIES (Tables)	12 Months Ended
	Dec. 31, 2014
INVESTMENT SECURITIES
Schedule of amortized cost, gross unrealized gains, gross unrealized losses and fair value by major categories of available-for-sale securities
			Amortized				Gross			Gross			Fair
			Cost				Unrealized			Unrealized			Value
							Gains			Losses
							(In thousands)
	As of December 31, 2014
	Investment securities available-for-sale:
	U.S. Treasury securities		$	873,101			$	1,971		$	(1,637	)	$	873,435
	U.S. government agency and U.S. government sponsored enterprise debt securities		311,927				490			(1,393		)	311,024
	U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities:
	Commercial mortgage-backed securities		140,957				1,056			(593		)	141,420
	Residential mortgage-backed securities		785,412				9,754			(4,078		)	791,088
	Municipal securities		245,408				6,202			(1,162		)	250,448
	Other residential mortgage-backed securities:
	Investment grade (1)		52,694				1,359			(135		)	53,918
	Other commercial mortgage-backed securities:
	Investment grade (1)		34,000				53			—			34,053
	Corporate debt securities:
	Investment grade (1)		116,236				—			(1,054		)	115,182
	Non-investment grade (1)		17,881				—			(3,200		)	14,681
	Other securities		41,589				243			(716		)	41,116
	Total investment securities available-for-sale		$	2,619,205			$	21,128		$	(13,968	)	$	2,626,365
	As of December 31, 2013
	Investment securities available-for-sale:
	U.S. Treasury securities		$	495,053			$	201		$	(3,622	)	$	491,632
	U.S. government agency and U.S. government sponsored enterprise debt securities		406,807				242			(12,726		)	394,323
	U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities:
	Commercial mortgage-backed securities		182,257				1,062			(4,449		)	178,870
	Residential mortgage-backed securities		892,435				7,729			(14,927		)	885,237
	Municipal securities		297,390				1,122			(17,533		)	280,979
	Other residential mortgage-backed securities:
	Investment grade (1)		48,129				—			(1,802		)	46,327
	Other commercial mortgage-backed securities:
	Investment grade (1)		51,000				617			—			51,617
	Corporate debt securities:
	Investment grade (1)		312,726				613			(3,344		)	309,995
	Non-investment grade (1)		20,668				62			(5,629		)	15,101
	Other securities		80,025				555			(864		)	79,716
	Total investment securities available-for-sale		$	2,786,490			$	12,203		$	(64,896	)	$	2,733,797
	-1	Investment securities rated BBB- or higher by S&P, or Baa3 or higher by Moody are considered investment grade.  Conversely, investment securities rated below BBB- by S&P, or below Baa3 by Moody are considered non-investment grade.
Schedule of sales of investment securities
			2014				2013			2012
							(In thousands)
	Proceeds from sales		$	623,689			$	663,569		$	1,230,134
	Gross realized gains		$	10,978			$	13,904		$	28,211
	Gross realized losses		$	127		$(1)	$	1,815		$	27,454
	Related tax expense		$	4,557			$	5,077		$	318
	-1	The gross $127 thousand of losses resulted from the investment securities acquired from MetroCorp which were sold immediately after the acquisition closed.
Schedule of other than temporary impairment, credit losses recognized in earnings
			2014				2013			2012
			(In thousands)
	Beginning balance		$	115,511			$	115,511		$	115,412
	Addition of OTTI that was not previously recognized		—				—			—
	Additional increases to the amount related to the credit loss for which an OTTI was previously recognized		—				—			99
	Reduction for securities sold		(3,173		)		—			—
	Ending balance		$	112,338			$	115,511		$	115,511
Gross unrealized losses and related fair values of investment securities available-for-sale
			Less Than 12 Months							12 Months or More						Total
			Fair				Unrealized			Fair			Unrealized			Fair		Unrealized
			Value				Losses			Value			Losses			Value		Losses
			(In thousands)
	As of December 31, 2014
	Investment securities available-for-sale:
	U.S. Treasury securities		$	170,260			$	(266	)	$	163,800		$	(1,371	)	$	334,060	$	(1,637	)
	U.S. government agency and U.S. government sponsored enterprise debt securities		69,438				(504		)	124,104			(889		)	193,542		(1,393		)
	U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities:
	Commercial mortgage-backed securities		45,405				(257		)	16,169			(336		)	61,574		(593		)
	Residential mortgage-backed securities		81,927				(270		)	241,047			(3,808		)	322,974		(4,078		)
	Municipal securities		6,391				(26		)	61,107			(1,136		)	67,498		(1,162		)
	Other residential mortgage-backed securities:
	Investment grade		—				—			7,217			(135		)	7,217		(135		)
	Corporate debt securities:
	Investment grade		25,084				(12		)	90,098			(1,042		)	115,182		(1,054		)
	Non-investment grade		—				—			14,681			(3,200		)	14,681		(3,200		)
	Other securities		15,885				(716		)	—			—			15,885		(716		)
	Total investment securities available-for-sale		$	414,390			$	(2,051	)	$	718,223		$	(11,917	)	$	1,132,613	$	(13,968	)
			Less Than 12 Months							12 Months or More						Total
			Fair				Unrealized			Fair			Unrealized			Fair		Unrealized
			Value				Losses			Value			Losses			Value		Losses
			(In thousands)
	As of December 31, 2013
	Investment securities available-for-sale:
	U.S. Treasury securities		$	337,248			$	(3,622	)	$	—		$	—		$	337,248	$	(3,622	)
	U.S. government agency and U.S. government sponsored enterprise debt securities		387,097				(12,726		)	—			—			387,097		(12,726		)
	U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities:
	Commercial mortgage-backed securities		114,754				(3,280		)	16,065			(1,169		)	130,819		(4,449		)
	Residential mortgage-backed securities		502,285				(10,570		)	92,540			(4,357		)	594,825		(14,927		)
	Municipal securities		173,782				(10,765		)	47,892			(6,768		)	221,674		(17,533		)
	Other residential mortgage-backed securities:
	Investment grade		46,327				(1,802		)	—			—			46,327		(1,802		)
	Corporate debt securities:
	Investment grade		193,482				(1,538		)	79,442			(1,806		)	272,924		(3,344		)
	Non-investment grade		—				—			14,422			(5,629		)	14,422		(5,629		)
	Other securities		48,098				(864		)	—			—			48,098		(864		)
	Total investment securities available-for-sale		$	1,803,073			$	(45,167	)	$	250,361		$	(19,729	)	$	2,053,434	$	(64,896	)
Scheduled maturities of investment securities
			Amortized				Estimated
			Cost				Fair Value
			(In thousands)
	Due within one year		$	343,193			$	339,814
	Due after one year through five years		1,018,469				1,022,566
	Due after five years through ten years		328,317				329,172
	Due after ten years		929,226				934,813
	Total investment securities available-for-sale		$	2,619,205			$	2,626,365

DERIVATIVES_Tables

DERIVATIVES (Tables)	12 Months Ended
	Dec. 31, 2014
DERIVATIVES
Notional or contractual Amounts and fair values for derivatives
			31-Dec-14												31-Dec-13
			Notional				Fair Value								Notional				Fair Value
			Amount				Derivative				Derivative				Amount				Derivative				Derivative
							Assets (1)				Liabilities (1)								Assets (1)				Liabilities (1)
			(In thousands)
	Derivatives designated as hedging instruments:
	Interest rate swaps on certificates of deposits		$	132,667			$	—			$	9,922			$	135,000			$	—			$	16,906
	Total derivatives designated as hedging instruments		$	132,667			$	—			$	9,922			$	135,000			$	—			$	16,906
	Derivatives not designated as hedging instruments:
	Foreign exchange options		$	85,614			$	6,136			$	—			$	85,614			$	6,290			$	—
	Embedded derivative liabilities		47,838				—				3,392				51,505				—				3,655
	Interest rate swaps and caps		4,858,391				41,534				41,779				3,834,072				28,078				26,352
	Foreign exchange contracts		680,629				8,123				9,171				635,428				6,181				3,349
	Total derivatives not designated as hedging instruments		$	5,672,472			$	55,793			$	54,342			$	4,606,619			$	40,549			$	33,356
	(1) Derivative assets are included in other assets. Derivative liabilities are included in other liabilities and deposits.
Net gains (losses) recognized in the Income Statement related to derivatives in fair value hedging relationships
		Years ended December 31,
		2014				2013				2012
		(In thousands)
	Gains (losses) recorded in interest expense:
	Recognized on interest rate swaps	$	6,885			$	(9,255	)		$	(1,076	)
	Recognized on certificates of deposits	(6,784		)		9,675				4,686
	Net amount recognized on fair value hedges (ineffective portion)	$	101			$	420			$	3,610
	Net interest expense recognized on interest rate swaps	$	(6,703	)		$	(3,153	)		$	(3,793	)
Net gains (losses) recognized in the Income Statement related to derivatives not designated as hedging instruments
			Location in		Year Ended December 31,
			Consolidated
			Statements of Income		2014				2013				2012
					(In thousands)
	Derivatives not designated as hedging instruments:
	Equity swap agreements		Other operating income		$	—			$	—			$	2
	Foreign exchange options		Foreign exchange income		103				653				389
	Foreign exchange options with embedded derivatives		Other operating expense		5				23				101
	Interest rate swaps and caps		Other operating income		(1,865		)		1,582				592
	Foreign exchange contracts		Foreign exchange income		(3,880		)		2,624				(228		)
			Total net (losses)		$	(5,637	)		$	4,882			$	856
Balance sheet offsetting of Derivative assets and liabilities and the respective collateral received or pledged in the form of other finanical instruments, which are generally marketable securities
			As of December 31, 2014
			(In thousands)
			Gross Amounts				Gross Amounts				Net Amounts of				Gross Amounts Not Offset on the
			of Recognized				Offset on the				Assets Presented				Consolidated Balance Sheets
			Assets				Consolidated				on the
							Balance Sheet				Consolidated
	Assets										Balance Sheet				Financial					Collateral					Net Amount
															Instruments					Received
	Derivatives		$	12,396			$	—			$	12,396			$	(5,725	)	(1)		$	(3,463	)	(2)		$	3,208
			Gross Amounts				Gross Amounts				Net Amounts of				Gross Amounts Not Offset on the
			of Recognized				Offset on the				Liabilities				Consolidated Balance Sheets
			Liabilities				Consolidated				Presented on the
							Balance Sheet				Consolidated
	Liabilities										Balance Sheet				Financial					Collateral					Net Amount
															Instruments					Posted
	Derivatives		$	56,505			$	—			$	56,505			$	(5,725	)	(1)		$	(49,951	)	(3)		$	829
			As of December 31, 2013
			(In thousands)
			Gross Amounts				Gross Amounts				Net Amounts of				Gross Amounts Not Offset on the
			of Recognized				Offset on the				Assets Presented				Consolidated Balance Sheets
			Assets				Consolidated				on the
							Balance Sheet				Consolidated
	Assets										Balance Sheet				Financial					Collateral					Net Amount
															Instruments					Received
	Derivatives		$	16,043			$	—			$	16,043			$	(11,363	)	(1)		$	(4,680	)	(2)		$	—
			Gross Amounts				Gross Amounts				Net Amounts of				Gross Amounts Not Offset on the
			of Recognized				Offset on the				Liabilities				Consolidated Balance Sheets
			Liabilities				Consolidated				Presented on the
							Balance Sheet				Consolidated
	Liabilities										Balance Sheet				Financial					Collateral					Net Amount
															Instruments					Posted
	Derivatives		$	33,849			$	—			$	33,849			$	(11,363	)	(1)		$	(22,486	)	(3)		$	—
	-1	Represents the netting of derivative receivable and payable balance for the same counterparty under enforceable master netting arrangements if the Company has elected to net.
	-2	Represents cash and securities received against derivative assets with the same counterparty that are subject to enforceable master netting arrangements. Includes approximately $3.5 million of cash collateral received as of December 31, 2014.
	-3	Represents cash and securities pledged against derivative liabilities with the same counterparty that are subject to enforceable master netting arrangements. Includes approximately $12.8 million and $187 thousand of cash collateral posted as of December 31, 2014 and December 31, 2013, respectively.

COVERED_ASSETS_AND_FDIC_INDEMN1

COVERED ASSETS AND FDIC INDEMNIFICATION ASSET (Tables)	12 Months Ended
	Dec. 31, 2014
Schedule of Loans and Leases Receivable, Allowance for Credit Losses
Composition of covered loans
			Year Ended December 31,
			2014					2013
			(In thousands)
	CRE		$	705,665				$	1,103,530
	Construction and land		46,054					163,833
	Total CRE		751,719					1,267,363
	C&I		252,986					426,621
	Residential single-family		240,650					290,095
	Residential multifamily		296,599					403,508
	Total residential		537,249					693,603
	Other consumer		62,986					73,973
	Total covered loans		1,604,940			(1)		2,461,560			(2)
	Covered discount		(127,246		)			(265,917		)
	Net valuation of loans		1,477,694					2,195,643
	Allowance for loan losses on covered loans		(3,505		)			(7,745		)
	Total covered loans, net		$	1,474,189				$	2,187,898
	Collectively evaluated for impairment		$	253,312		(1)		$	320,185		(2)
	Acquired with deteriorated credit quality		1,224,382					1,875,458
	Total		$	1,477,694				$	2,195,643
	-1	Includes $253.3 million of covered advances comprised of $154.8 million, $59.4 million, $27.3 million and $11.8 million of C&I, CRE, consumer and residential loans, respectively.
	-2	Includes $320.2 million of covered advances comprised of $230.6 million, $46.7 million, $30.9 million and $12.0 million of C&I, CRE, consumer and residential loans, respectively.
Schedule of credit risk rating categories for the covered loans by portfolio segments
			Pass/Watch				Special				Substandard				Doubtful			Total
							Mention
			(In thousands)
	31-Dec-14
	CRE		$	579,133			$	12,575			$	113,957			$	—		$	705,665
	Construction and land		18,090				8,515				19,449				—			46,054
	Total CRE		597,223				21,090				133,406				—			751,719
	C&I		217,975				5,723				29,288				—			252,986
	Residential single-family		232,139				474				8,037				—			240,650
	Residential multifamily		247,893				—				48,706				—			296,599
	Total residential		480,032				474				56,743				—			537,249
	Other consumer		62,010				141				835				—			62,986
	Total principal balance		$	1,357,240			$	27,428			$	220,272			$	—		$	1,604,940
			Pass/Watch				Special				Substandard				Doubtful			Total
							Mention
			(In thousands)
	31-Dec-13
	CRE		$	857,376			$	27,851			$	211,835			$	6,468		$	1,103,530
	Construction and land		41,847				9,472				111,616				898			163,833
	Total CRE		899,223				37,323				323,451				7,366			1,267,363
	C&I		378,086				4,635				43,797				103			426,621
	Residential single-family		281,246				733				8,116				—			290,095
	Residential multifamily		373,024				785				29,699				—			403,508
	Total residential		654,270				1,518				37,815				—			693,603
	Other consumer		72,053				128				1,792				—			73,973
	Total principal balance		$	2,003,632			$	43,604			$	406,855			$	7,469		$	2,461,560
Covered nonperforming assets
			December 31,
			2014				2013
			(In thousands)
	Covered nonaccrual loans(1) (2) (3)		$	62,665			$	126,895
	Other real estate owned covered, net		4,499				21,373
	Total covered nonperforming assets		$	67,164			$	148,268
	-1	Covered nonaccrual loans include loans that meet the criteria for nonaccrual but have a yield accreted through interest income under ASC 310-30.  All losses on covered loans are 80% reimbursed by the FDIC.
	-2	Net of discount.
	-3	Includes $10.1 million and $17.7 million of covered advances as of December 31, 2014 and December 31, 2013, respectively; and $52.6 million and $109.2 million of PCI loans as of December 31, 2014 and December 31, 2013, respectively.
Schedule of troubled debt restructurings related to covered loans activity
							Year Ended December 31,
							2014				2013
							(In thousands)
	Beginning balance						$	116,007			$	157,736
	Additions						1,264				35,865
	Transfers to covered OREO						(1,230		)		—
	Charge-offs						(1,504		)		(10,167		)
	Paydowns/Reductions						(71,810		)		(67,427		)
	Ending Balance						$	42,727			$	116,007
Changes in the accretable yield for the PCI covered loans
			Year Ended December 31,
			2014				2013				2012
			(In thousands)
	Beginning balance		$	461,545			$	556,986			$	785,165
	Additions		—				—				—
	Accretion		(214,209		)		(347,010		)		(382,132		)
	Changes in expected cash flows		59,188				251,569				153,953
	Ending balance		$	306,524			$	461,545			$	556,986
FDIC indemnification asset liabilities activity
			Year Ended December 31,
			2014				2013
			(In thousands)
	Beginning balance		$	74,708			$	316,313
	Amortization		(101,638		)		(99,055		)
	Reductions (1)		(33,595		)		(95,536		)
	Estimate of FDIC repayment (2)		(35,581		)		(47,014		)
	Ending Balance		$	(96,106	)		$	74,708
	-1	Reductions relate to charge-offs, partial prepayments, loan payoffs and loan sales which result in a corresponding reduction of the indemnification asset.
	-2	This represents the change in the calculated estimate the Company will be required to pay the FDIC at the end of the FDIC shared-loss agreements, due to lower thresholds of losses.
Summary of FDIC receivable activity
			Year Ended December 31,
			2014				2013
			(In thousands)
	Beginning balance		$	30,261			$	73,091
	Net (reduction) addition due to recovery or eligible expense/loss		(30,601		)		12,996
	Payments to (received from) the FDIC		1,343				(55,826		)
	Ending balance		$	1,003			$	30,261
Covered Loans
Allowance for loan losses disclosures
Summary of the activity in the allowance for loan losses and PCI covered loans and covered advances
			Year Ended December 31,
			2014												2013									2012
			Covered				PCI				Total				Covered			PCI		Total				Covered			PCI		Total
			Advances				Covered								Advances			Covered						Advances			Covered
							Loans											Loans									Loans
			(In thousands)
	Beginning balance		$	5,476			$	2,269			$	7,745			$	5,153		$	—	$	5,153			$	6,647		$	—	$	6,647
	Provision for (reversal of) loan losses		6,878				(1,845		)		5,033				1,759			2,269		4,028				5,016			—		5,016
	Charge-offs		(10,836		)		—				(10,836		)		(1,436		)	—		(1,436		)		(6,510		)	—		(6,510		)
	Recoveries		1,563				—				1,563				—			—		—				—			—		—
	Ending balance		$	3,081			$	424			$	3,505			$	5,476		$	2,269	$	7,745			$	5,153		$	—	$	5,153
	Ending balance allocated to:
	Collectively evaluated for impairment		$	3,081			$	—			$	3,081		(1)	$	5,476		$	—	$	5,476		(2)	$	5,153		$	—	$	5,153		(3)
	Acquired with deteriorated credit quality		—				424				424				—			2,269		2,269				—			—		—
	Ending balance		$	3,081			$	424			$	3,505			$	5,476		$	2,269	$	7,745			$	5,153		$	—	$	5,153
	-1	Allowance for loan losses of $2.0 million, $676 thousand, $223 thousand and $166 thousand are allocated to C&I, CRE, consumer and residential loans, respectively.
	-2	Allowance for loan losses of $3.2 million, $1.8 million, $341 thousand and $176 thousand are allocated to C&I, CRE, consumer and residential loans, respectively.
	-3	Allowance for loan losses of $2.4 million, $2.5 million and $194 thousand and $87 thousand are allocated to C&I, CRE, consumer and residential loans, respectively.

NONCOVERED_LOANS_AND_ALLOWANCE1

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Tables)	12 Months Ended
	Dec. 31, 2014
NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES
Schedule of composition of non-covered loans
			31-Dec-14				31-Dec-13
			(In thousands)
	CRE:
	Income producing		$	5,611,485			$	4,301,030
	Construction		313,811				140,186
	Land		208,750				143,861
	Total CRE		6,134,046				4,585,077
	C&I:
	Commercial business		7,031,350				4,637,056
	Trade finance		806,744				723,137
	Total C&I		7,838,094				5,360,193
	Residential:
	Single-family		3,642,978				3,192,875
	Multifamily		1,177,690				992,434
	Total residential		4,820,668				4,185,309
	Consumer:
	Student loans		—				679,220
	Other consumer		1,456,643				868,518
	Total consumer		1,456,643				1,547,738
	Total non-covered loans (1)		20,249,451				15,678,317
	Unearned fees, premiums, and discounts, net		2,804				(23,672		)
	Allowance for loan losses on non-covered loans		(258,174		)		(241,930		)
	Non-covered loans, net		$	19,994,081			$	15,412,715
	-1	Loans net of ASC 310-30 discount.
Summary of credit risk rating categories for the non-covered loans
			Pass/Watch				Special				Substandard				Doubtful				Loss				Total
							Mention
			(In thousands)
	31-Dec-14
	CRE:
	Income producing		$	5,244,022			$	54,431			$	313,032			$	—			$	—			$	5,611,485
	Construction		306,923				—				6,888				—				—				313,811
	Land		179,319				5,701				23,730				—				—				208,750
	C&I:
	Commercial business		6,783,051				128,578				119,133				533				55				7,031,350
	Trade finance		766,575				10,193				29,976				—				—				806,744
	Residential:
	Single-family		3,624,097				3,143				15,738				—				—				3,642,978
	Multifamily		1,096,572				5,124				75,994				—				—				1,177,690
	Consumer:
	Student loans		—				—				—				—				—				—
	Other consumer		1,452,953				1,005				2,685				—				—				1,456,643
	Total		$	19,453,512			$	208,175			$	587,176			$	533			$	55			$	20,249,451
			Pass/Watch				Special				Substandard				Doubtful				Loss				Total
							Mention
			(In thousands)
	31-Dec-13
	CRE:
	Income producing		$	4,032,269			$	56,752			$	212,009			$	—			$	—			$	4,301,030
	Construction		127,138				6,160				6,888				—				—				140,186
	Land		116,000				9,304				18,557				—				—				143,861
	C&I:
	Commercial business		4,400,847				92,315				143,894				—				—				4,637,056
	Trade finance		681,345				22,099				19,693				—				—				723,137
	Residential:
	Single-family		3,167,337				8,331				17,207				—				—				3,192,875
	Multifamily		923,697				1,634				67,103				—				—				992,434
	Consumer:
	Student loans		677,094				445				1,681				—				—				679,220
	Other consumer		865,752				244				2,522				—				—				868,518
	Total		$	14,991,479			$	197,284			$	489,554			$	—			$	—			$	15,678,317
Aging analysis of the Company's non-covered loans and loans held for sale
			Accruing				Accruing				Total				Nonaccrual				Nonaccrual				Total				Current				Total
			Loans				Loans				Accruing				Loans Less				Loans				Nonaccrual				Accruing
			30-59 Days				60-89 Days				Past Due				Than 90 Days				90 or More				Loans				Loans
			Past Due				Past Due				Loans				Past Due				Days Past Due
			(In thousands)
	31-Dec-14
	CRE:
	Income producing		$	14,171			$	3,593			$	17,764			$	29,576			$	9,109			$	38,685			$	5,555,036			$	5,611,485
	Construction		—				—				—				—				6,888				6,888				306,923				313,811
	Land		—				—				—				254				2,502				2,756				205,994				208,750
	C&I:
	Commercial business		3,073				2,884				5,957				5,514				14,689				20,203				7,005,190				7,031,350
	Trade finance		—				—				—				73				—				73				806,671				806,744
	Residential:
	Single-family		6,375				1,294				7,669				2,894				4,936				7,830				3,627,479				3,642,978
	Multifamily		4,350				507				4,857				12,460				8,336				20,796				1,152,037				1,177,690
	Consumer:
	Student loans		—				—				—				—				—				—				—				—
	Other consumer		2,154				162				2,316				115				540				655				1,453,672				1,456,643
	Loans held for sale		642				175				817				—				3,157				3,157				41,976				45,950
	Total (1)		$	30,765			$	8,615			$	39,380			$	50,886			$	50,157			$	101,043			$	20,154,978			$	20,295,401
	Unearned fees, premiums and discounts, net																														2,804
	Total recorded investment in non-covered loans and loans held for sale																														$	20,298,205
	-1	Loans net of ASC 310-30 discount.
			Accruing				Accruing				Total				Nonaccrual				Nonaccrual				Total				Current				Total
			Loans				Loans				Accruing				Loans Less				Loans				Nonaccrual				Accruing
			30-59 Days				60-89 Days				Past Due				Than 90 Days				90 or More				Loans				Loans
			Past Due				Past Due				Loans				Past Due				Days Past Due
			(In thousands)
	31-Dec-13
	CRE:
	Income producing		$	12,746			$	1,798			$	14,544			$	13,924			$	22,549			$	36,473			$	4,250,013			$	4,301,030
	Construction		—				—				—				—				6,888				6,888				133,298				140,186
	Land		—				—				—				265				3,223				3,488				140,373				143,861
	C&I:
	Commercial business		3,428				6,259				9,687				6,437				15,486				21,923				4,605,446				4,637,056
	Trade finance		—				—				—				—				909				909				722,228				723,137
	Residential:
	Single-family		4,694				922				5,616				—				11,218				11,218				3,176,041				3,192,875
	Multifamily		8,580				531				9,111				19,661				7,972				27,633				955,690				992,434
	Consumer:
	Student loans		541				445				986				—				1,681				1,681				676,553				679,220
	Other consumer		293				1				294				175				1,263				1,438				866,786				868,518
	Loans held for sale		—				—				—				—				—				—				204,970				204,970
	Total		$	30,282			$	9,956			$	40,238			$	40,462			$	71,189			$	111,651			$	15,731,398			$	15,883,287
	Unearned fees, premiums and discounts, net																														(23,672		)
	Total recorded investment in non-covered loans and loans held for sale																														$	15,859,615
Summary of new troubled debt restructurings modifications on the non-covered loan portfolio
			Loans Modified as TDRs During the Year Ended December 31,
			2014															2013															2012
			Number			Pre-Modification				Post-Modification				Financial				Number			Pre-Modification				Post-Modification				Financial				Number	Pre-Modification		Post-Modification		Financial
			of			Outstanding				Outstanding				Impact (2)				of			Outstanding				Outstanding				Impact (2)				of	Outstanding		Outstanding		Impact (2)
			Contracts			Recorded				Recorded								Contracts			Recorded				Recorded								Contracts	Recorded		Recorded
						Investment				Investment (1)											Investment				Investment (1)									Investment		Investment (1)
			($ in thousands)
	CRE:
	Income producing		6			$	8,829			$	8,624			$	43			6			$	26,021			$	17,456			$	219			8	$	10,118	$	8,162	$	1,169
	Construction		—			$	—			$	—			$	—			—			$	—			$	—			$	—			—	$	—	$	—	$	—
	Land		—			$	—			$	—			$	—			—			$	—			$	—			$	—			3	$	1,610	$	1,059	$	395
	C&I:
	Commercial business		13			$	4,379			$	3,089			$	2,205			6			$	16,220			$	15,624			$	4,274			14	$	5,101	$	4,374	$	560
	Trade finance		1			$	190			$	73			$	14			—			$	—			$	—			$	—			2	$	2,510	$	579	$	1,506
	Residential:
	Single-family		9			$	11,454			$	8,269			$	—			—			$	—			$	—			$	—			12	$	6,227	$	5,556	$	938
	Multifamily		6			$	5,471			$	3,705			$	7			1			$	1,093			$	1,071			$	—			16	$	28,736	$	28,153	$	3,344
	Consumer:
	Other consumer		1			$	509			$	504			$	—			1			$	651			$	639			$	—			1	$	108	$	108	$	—
	-1	Includes subsequent payments after modification.
	-2	The financial impact includes charge-offs and specific reserves recorded at modification date.
Troubled debt restructurings that have subsequently defaulted
			Loans Modified as TDRs that Subsequently Defaulted
			During the Year Ended December 31,
			2014							2013							2012
			Number of			Recorded				Number of			Recorded				Number of			Recorded
			Contracts			Investment				Contracts			Investment				Contracts			Investment
			($ in thousands)
	CRE:
	Income producing		—			$	—			—			$	—			1			$	271
	Construction		—			$	—			—			$	—			—			$	—
	Land		—			$	—			—			$	—			—			$	—
	C&I:
	Commercial business		1			$	957			1			$	570			2			$	33
	Trade finance		—			$	—			—			$	—			—			$	—
	Residential:
	Single-family		—			$	—			—			$	—			2			$	2,830
	Multifamily		—			$	—			—			$	—			1			$	378
	Consumer:
	Other consumer		—			$	—			1			$	639			—			$	—
Summary of impaired non-covered loans
			Unpaid				Recorded				Recorded				Total				Related
			Principal				Investment				Investment				Recorded				Allowance
			Balance				With No				With				Investment (1)
							Allowance				Allowance
			(In thousands)
	As of December 31, 2014
	CRE:
	Income producing		$	57,805			$	34,399			$	15,646			$	50,045			$	1,581
	Construction		6,888				6,888				—				6,888				—
	Land		13,291				2,838				5,622				8,460				1,906
	C&I:
	Commercial business		42,396				10,552				25,717				36,269				15,174
	Trade finance		280				—				274				274				28
	Residential:
	Single-family		17,838				5,137				11,398				16,535				461
	Multifamily		37,624				21,500				12,890				34,390				313
	Consumer:
	Other consumer		1,259				1,151				108				1,259				1
	Total		$	177,381			$	82,465			$	71,655			$	154,120			$	19,464
			Unpaid				Recorded				Recorded				Total				Related
			Principal				Investment				Investment				Recorded				Allowance
			Balance				With No				With				Investment (1)
							Allowance				Allowance
			(In thousands)
	As of December 31, 2013
	CRE:
	Income producing		$	73,777			$	39,745			$	25,523			$	65,268			$	5,976
	Construction		6,888				6,888				—				6,888				—
	Land		17,390				4,372				7,908				12,280				2,082
	C&I:
	Commercial business		48,482				10,850				27,487				38,337				13,787
	Trade finance		2,771				438				752				1,190				752
	Residential:
	Single-family		15,814				13,585				1,588				15,173				207
	Multifamily		43,821				30,899				10,215				41,114				1,339
	Consumer:
	Student loans		1,749				1,681				—				1,681				—
	Other consumer		1,945				1,546				—				1,546				—
	Total		$	212,637			$	110,004			$	73,473			$	183,477			$	24,143
	-1	Excludes $10.1 million and $17.7 million of covered non-accrual loans as of December 31, 2014 and December 31, 2013, respectively, accounted for under ASC 310-10, of which some loans have additional partial balances accounted for under ASC 310-30.
Schedule of average recorded investment in impaired loans and the amount of interest income recognized on impaired loans by portfolio segment
			Year Ended December 31,
			2014								2013
			Average				Recognized				Average				Recognized
			recorded				interest				recorded				interest
			investment				income (1)				investment				income (1)
			(In thousands)
	CRE:
	Income producing		$	54,544			$	1,249			$	71,856			$	2,480
	Construction		6,888				—				6,888				—
	Land		8,633				298				12,453				496
	C&I:
	Commercial business		36,528				833				38,294				735
	Trade finance		336				15				1,603				11
	Residential:
	Single-family		16,413				342				15,322				154
	Multifamily		37,128				830				35,799				850
	Consumer:
	Student loans		—				—				1,664				—
	Other consumer		1,259				47				1,561				4
	Total impaired loans (excluding PCI)		$	161,729			$	3,614			$	185,440			$	4,730
	-1	Includes interest recognized on accruing TDRs.  Interest payments received on nonaccrual loans are reflected as a reduction of principal and not as interest income.
Allowance for loan losses disclosures
Recorded investment in total loans non-covered receivable by portfolio segment, disaggregated by impairment methodology
			CRE				C&I				Residential				Consumer				Total
			(In thousands)
	31-Dec-14
	Individually evaluated for impairment		$	65,393			$	36,543			$	50,925			$	1,259			$	154,120
	Collectively evaluated for impairment		5,977,437				7,796,239				4,768,541				1,455,384				19,997,601
	Acquired with deteriorated credit quality		91,216				5,312				1,202				—				97,730
	Ending balance		$	6,134,046			$	7,838,094			$	4,820,668			$	1,456,643			$	20,249,451
			CRE				C&I				Residential				Consumer				Total
			(In thousands)
	31-Dec-13
	Individually evaluated for impairment		$	84,436			$	39,527			$	56,287			$	3,227			$	183,477
	Collectively evaluated for impairment		4,500,641				5,320,666				4,129,022				1,544,511				15,494,840
	Ending balance		$	4,585,077			$	5,360,193			$	4,185,309			$	1,547,738			$	15,678,317
Summary of the changes in the accretable yield for the PCI loans acquired from MetroCorp
					Year Ended
					31-Dec-14
					(In thousands)
	Beginning balance				$	—
	Additions				6,745
	Accretion				(4,960		)
	Changes in expected cash flows				3,379
	Ending Balance				$	5,164
Non-covered loans
Allowance for loan losses disclosures
Summary of the activity in the allowance for loan losses on non-covered loans
			CRE				C&I				Residential				Consumer				Unallocated				Total
			(In thousands)
	Year Ended December 31, 2014
	Beginning balance		$	64,677			$	115,184			$	50,717			$	11,352			$	—			$	241,930
	Provision for (reversal of) loan losses		6,107				40,371				(8,168		)		4,240				1,575				44,125
	Allowance for unfunded loan commitments and letters of credit		—				—				—				—				(1,575		)		(1,575		)
	Charge-offs		(3,294		)	(1)	(29,592		)		(1,103		)		(5,793		)		—				(39,782		)
	Recoveries		1,982				8,635				2,410				449				—				13,476
	Net (charge-offs) recoveries		(1,312		)		(20,957		)		1,307				(5,344		)		—				(26,306		)
	Ending balance		$	69,472			$	134,598			$	43,856			$	10,248			$	—			$	258,174
	Ending balance allocated to:
	Individually evaluated for impairment		$	3,487			$	15,202			$	774			$	1			$	—			$	19,464
	Collectively evaluated for impairment		65,695				119,396				43,082				10,247				—				238,420
	Acquired with deteriorated credit quality		290				—				—				—				—				290
	Ending balance		$	69,472			$	134,598			$	43,856			$	10,248			$	—			$	258,174
	(1) Includes a charge-off of $523 thousand related to PCI loans acquired from MetroCorp.
			CRE				C&I				Residential				Consumer				Unallocated				Total
		(In thousands)
	Year Ended December 31, 2013
	Beginning balance		$	69,856			$	105,376			$	49,349			$	4,801			$	—			$	229,382
	(Reversal of) provision for loan losses		(6,615		)		12,821				1,918				8,055				2,157				18,336
	Allowance for unfunded loan commitments and letters of credit		—				—				—				—				(2,157		)		(2,157		)
	Charge-offs		(3,357		)		(7,405		)		(3,197		)		(2,385		)		—				(16,344		)
	Recoveries		4,793				4,392				2,647				881				—				12,713
	Net recoveries (charge-offs)		1,436				(3,013		)		(550		)		(1,504		)		—				(3,631		)
	Ending balance		$	64,677			$	115,184			$	50,717			$	11,352			$	—			$	241,930
	Ending balance allocated to:
	Individually evaluated for impairment		$	8,058			$	14,539			$	1,546			$	—			$	—			$	24,143
	Collectively evaluated for impairment		56,619				100,645				49,171				11,352				—				217,787
	Ending balance		$	64,677			$	115,184			$	50,717			$	11,352			$	—			$	241,930
			CRE				C&I				Residential				Consumer				Unallocated				Total
		(In thousands)
	Year Ended December 31, 2012
	Beginning balance		$	66,457			$	87,020			$	52,180			$	4,219			$	—			$	209,876
	Provision for (reversal of) loan losses		20,977				35,204				3,255				2,295				(1,563		)		60,168
	Allowance for unfunded loan commitments and letters of credit		—				—				—				—				1,563				1,563
	Charge-offs		(27,060		)		(21,818		)		(7,700		)		(1,824		)		—				(58,402		)
	Recoveries		9,482				4,970				1,614				111				—				16,177
	Net (chargeoffs) recoveries		(17,578		)		(16,848		)		(6,086		)		(1,713		)		—				(42,225		)
	Ending balance		$	69,856			$	105,376			$	49,349			$	4,801			$	—			$	229,382
	Ending balance allocated to:
	Individually evaluated for impairment		$	5,561			$	2,835			$	3,131			$	—			$	—			$	11,527
	Collectively evaluated for impairment		64,295				102,541				46,218				4,801				—				217,855
	Ending balance		$	69,856			$	105,376			$	49,349			$	4,801			$	—			$	229,382

GOODWILL_AND_OTHER_INTANGIBLE_1

GOODWILL AND OTHER INTANGIBLE ASSETS (Tables)	12 Months Ended
	Dec. 31, 2014
GOODWILL AND OTHER INTANGIBLE ASSETS
Schedule of changes in the carrying amount of goodwill
		Year Ended December 31,
		2014		2013
		(In thousands)
	Beginning balance	$	337,438	$	337,438
	Addition from the MetroCorp acquisition(1)	131,995		—
	Ending Balance	$	469,433	$	337,438
	(1) Includes $11.0 million of tax and BOLI adjustments recorded in the fourth quarter of 2014.
Estimated future amortization expense of premiums on acquired deposits
	Estimates For The Years Ending December 31,	Amount
		(In thousands)
	2015	$	9,234
	2016	8,086
	2017	6,935
	2018	5,883
	2019	4,864
	Thereafter	10,307
	Total	$	45,309

CUSTOMER_DEPOSIT_ACCOUNTS_Tabl

CUSTOMER DEPOSIT ACCOUNTS (Tables)	12 Months Ended
	Dec. 31, 2014
CUSTOMER DEPOSIT ACCOUNTS
Summary of customer deposit account balances
		December 31,
		2014		2013
		(In thousands)
	Noninterest-bearing demand	$	7,381,030	$	5,821,899
	Interest-bearing checking	2,545,618		1,749,479
	Money market accounts	6,318,120		5,653,412
	Savings deposits	1,651,267		1,363,780
	Total core deposits	17,896,035		14,588,570
	Time deposits:
	Less than $100,000	1,662,046		1,678,850
	$100,000 or greater	4,450,693		4,145,498
	Total time deposits	6,112,739		5,824,348
	Total deposits	$	24,008,774	$	20,412,918
Scheduled maturities of time deposits
		$100,000 or		Less Than		Total
		Greater		$100,000
		(In thousands)
	2015	$	3,513,958	$	1,397,648	$	4,911,606
	2016	318,791		164,061		482,852
	2017	189,195		44,944		234,139
	2018	168,252		34,579		202,831
	2019	142,492		20,782		163,274
	Thereafter	118,005		32		118,037
	Total	$	4,450,693	$	1,662,046	$	6,112,739

FEDERAL_HOME_LOAN_BANK_ADVANCE1

FEDERAL HOME LOAN BANK ADVANCES AND LONG-TERM DEBT (Tables)	12 Months Ended
	Dec. 31, 2014
FEDERAL HOME LOAN BANK ADVANCES AND LONG-TERM DEBT
Schedule of the components of long-term debt
			December 31,
			2014			2013
			(In thousands)
	Junior subordinated debt		$	145,848		$	126,868
	Term loan		80,000			100,000
	Total long-term debt		$	225,848		$	226,868
Summary of pertinent information related to outstanding junior subordinated debt issued by each Trust
	Trust Name		Maturity Date (1)		Stated	Rate as of		December 31,
					Interest Rate	December 31, 2014		2014		2013
								($ in thousands)
	East West Capital Trust IV		Jul-34		3-month Libor + 2.55%	—		$	—	$	10,000
	East West Capital Trust V		Nov-34		3-month Libor + 1.80%	2.03	%	15,000		15,000
	East West Capital Trust VI		Sep-35		3-month Libor + 1.50%	1.74	%	20,000		20,000
	East West Capital Trust VII		Jun-36		3-month Libor + 1.35%	1.59	%	30,000		30,000
	East West Capital Trust VIII		Jun-37		3-month Libor + 1.40%	1.64	%	18,000		18,000
	East West Capital Trust IX		Sep-37		3-month Libor + 1.90%	2.14	%	30,000		30,000
	Metro Bank Trust		Dec-35		3-month Libor + 1.55%	1.79	%	35,000		—
	Total							$	148,000	$	123,000
	-1	All of the above debt instruments are subject to various call options.

INCOME_TAXES_Tables

INCOME TAXES (Tables)	12 Months Ended
	Dec. 31, 2014
INCOME TAXES
Components of provision for income taxes
		Year Ended December 31,
		2014				2013				2012
		(In thousands)
	Current income tax expense:
	Federal	$	153,211			$	131,236			$	148,572
	State	70,527				44,389				2,316
	Foreign	3,846				208				5,704
	Total current income tax expense	227,584				175,833				156,592
	Deferred income tax benefit:
	Federal	(116,241		)		(32,963		)		(38,749		)
	State	(37,665		)		(13,677		)		26,099
	Foreign	(706		)		1,612				—
	Total deferred income tax benefit	(154,612		)		(45,028		)		(12,650		)
	Provision for income taxes	$	72,972			$	130,805			$	143,942
Difference between the effective tax rate implicit in the consolidated financial statements and the statutory federal income tax rate
		Year Ended December 31,
		2014			2013			2012
	Federal income tax provision at statutory rate	35	%		35	%		35	%
	State franchise taxes, net of federal tax effect	5.1			4.7			4.3
	Tax credits	(21.5	)		(8.4	)		(5.3	)
	Other, net	(1.0	)		(0.6	)		(0.2	)
	Effective income tax rate	17.6	%		30.7	%		33.8	%
Tax effects of temporary differences that give rise to significant portions of the deferred tax assets (liabilities)
		December 31,
		2014														2013
		Federal				State				Foreign			Total			Federal			State			Foreign		Total
		(In thousands)
	Deferred tax liabilities:
	Core deposit intangibles	$	(15,748	)		$	(4,513	)		$	—		$	(20,261	)	$	(16,422	)	$	(4,642	)	$	—	$	(21,064	)
	Affordable housing partnerships and other investments	—				—				—			—			(14,158		)	(1,730		)	—		(15,888		)
	Fixed assets	(16,615		)		(4,101		)		—			(20,716		)	(15,594		)	(3,879		)	—		(19,473		)
	Federal Housing Loan Bank stock	(5,064		)		(1,475		)		—			(6,539		)	(11,337		)	(3,224		)	—		(14,561		)
	Deferred loan fees	(1,587		)		(454		)		—			(2,041		)	(1,976		)	(557		)	—		(2,533		)
	Purchased loan discounts	(51		)		(15		)		—			(66		)	(98		)	(28		)	—		(126		)
	State taxes	(8,244		)		—				—			(8,244		)	(1,079		)	—			—		(1,079		)
	Section 597 gain	(2,063		)		(64		)		—			(2,127		)	(48,370		)	(1,317		)	—		(49,687		)
	FDIC receivable	—				—				—			—			(245,907		)	(6,695		)	—		(252,602		)
	Acquired debt	(2,237		)		1,369				—			(868		)	(10,812		)	(1,042		)	—		(11,854		)
	Other, net	(1,652		)		(473		)		—			(2,125		)	(6,805		)	923			—		(5,882		)
	Total gross deferred tax (liabilities)	(53,261		)		(9,726		)		—			(62,987		)	(372,558		)	(22,191		)	—		(394,749		)
	Deferred tax assets:
	Affordable housing partnerships and other investments	1,768				4,870				—			6,638			—			—			—		—
	Allowance for loan losses and REO reserves	93,749				23,615				1,409			118,773			93,018			23,046			—		116,064
	FDIC receivable and clawback	36,630				11,736				—			48,366			—			—			—		—
	Deferred compensation	16,505				4,785				—			21,290			13,322			3,824			—		17,146
	Mortgage servicing assets	2,570				735				—			3,305			287			81			—		368
	Purchased loan premium	292				84				—			376			424			120			—		544
	Unrealized loss on securities	42,737				12,638				—			55,375			62,535			19,177			—		81,712
	Acquired loans and REOs	139,360				36,678				256			176,294			366,290			26,959			959		394,208
	Other, net	12,189				4,967				97			17,253			30,768			9,709			97		40,574
	Total gross deferred tax assets	345,800				100,108				1,762			447,670			566,644			82,916			1,056		650,616
	Valuation allowance	—				(316		)		—			(316		)	—			(337		)	—		(337		)
	Net deferred tax assets	$	292,539			$	90,066			$	1,762		$	384,367		$	194,086		$	60,388		$	1,056	$	255,530
Summary of the activity related to unrecognized tax benefits
		Year Ended December 31,
		2014				2013
		(In thousands)
	Beginning Balance	$	4,677			$	3,457
	Additions for tax positions of prior years	343				232
	Reductions for tax positions of prior years	—				—
	Additions for tax positions of current year					988
	Settlements	—				—
	Ending Balance	$	5,020			$	4,677

COMMITMENTS_AND_CONTINGENCIES_

COMMITMENTS AND CONTINGENCIES (Tables)	12 Months Ended
	Dec. 31, 2014
COMMITMENTS AND CONTINGENCIES.
Estimated future minimum rental payments under non-cancelable operating leases
	Estimates For The Years Ending December 31,	Amount
		(In thousands)
	2015	$	24,076
	2016	19,239
	2017	14,957
	2018	11,389
	2019	9,950
	Thereafter	30,910
	Total	$	110,521

STOCK_COMPENSATION_PLANS_Table

STOCK COMPENSATION PLANS (Tables)	12 Months Ended
	Dec. 31, 2014
STOCK COMPENSATION PLANS
Summary of stock options activity
		Shares		Weighted			Weighted		Aggregate
				Average			Average		Intrinsic
				Exercise			Remaining		Value
				Price			Contractual		(In thousands)
							Term
	Outstanding at beginning of year	406,731		$	26.72
	Granted	—		—
	Exercised	(234,101	)	21.09
	Forfeited	(130,514	)	38.76
	Outstanding at end of year	42,116		$	20.75		0.19 years		$	757
	Vested or expected to vest at year-end	42,116		$	20.75		0.19 years		$	757
	Exercisable at year-end	42,116		$	20.75		0.19 years		$	757
Schedule summarizing information about stock options outstanding
		Options Outstanding							Options Exercisable
	Range of	Number of		Weighted			Weighted		Number of			Weighted
	Exercise Prices	Outstanding		Average			Average		Exercisable			Average
		Options		Exercise			Remaining		Options			Exercise
				Price			Contractual Life					Price
	$10.00 to $14.99	2,365		$	14.95		1.02 years		2,365			$	14.95
	$20.00 to $24.99	39,751		$	21.09		0.14 years		39,751			$	21.09
	$10.00 to $24.99	42,116		$	20.75		0.19 years		42,116			$	20.75
Schedule of stock option grants, intrinsic value of options exercised, and total fair value of shares vested
		Year Ended December 31,
		2014			2013			2012
	Total intrinsic value of options exercised (in thousands)	$	3,546		$	926		$	978
	Total fair value of options vested (in thousands)	$	—		$	363		$	3,717
Schedule of share-based compensation, time-based and performance-based restricted stock awards activity
		2014
		Restricted Stock Awards
		Time-Based					Performance-Based
		Shares		Weighted			Shares			Weighted
				Average						Average
				Price						Price
	Outstanding at beginning of year	438,508		$	17.79		956,707			$	23.74
	Granted	43,210		33.19			603,697			36.85
	Vested	(343,722	)	15.91			(340,866	)		23.52
	Forfeited	(30,733	)	21.21			(57,228	)		29.71
	Outstanding at end of year	107,263		$	29.01		1,162,310			$	30.32

STOCKHOLDERS_EQUITY_AND_EARNIN1

STOCKHOLDERS' EQUITY AND EARNINGS PER SHARE (Tables)	12 Months Ended
	Dec. 31, 2014
STOCKHOLDERS' EQUITY AND EARNINGS PER SHARE
Earnings per share calculations
			Year Ended December 31, 2014
			Net Income				Number of Shares			Per Share Amounts
			(In thousands, except per share data)
	Net income		$	342,483
	Less:
	Preferred stock dividends		—
	Earnings allocated to participating securities		(502		)
	Basic EPS — income allocated to common stockholders		$	341,981			142,952			$	2.39
	Effect of dilutive securities:
	Stock options		—				67
	Restricted stock units		287				398
	Convertible preferred stock		—				—
	Warrants		—				146
	Diluted EPS — income allocated to common stockholders		$	342,268			143,563			$	2.38
			Year Ended December 31, 2013
			Net Income				Number of Shares			Per Share Amounts
			(In thousands, except per share data)
	Net income		$	295,045
	Less:
	Preferred stock dividends		(3,428		)
	Earnings allocated to participating securities		(1,692		)
	Basic EPS — income allocated to common stockholders		$	289,925			137,342			$	2.11
	Effect of dilutive securities:
	Stock options		—				71
	Restricted stock units		196				327
	Convertible preferred stock		3,428				1,834
	Diluted EPS — income allocated to common stockholders		$	293,549			139,574			$	2.1
			Year Ended December 31, 2012
			Net Income				Number of Shares			Per Share Amounts
			(In thousands, except per share data)
	Net income		$	281,650
	Less:
	Preferred stock dividends		(6,857		)
	Earnings allocated to participating securities		(3,279		)
	Basic EPS — income allocated to common stockholders		$	271,514			141,457			$	1.92
	Effect of dilutive securities:
	Stock options		—				29
	Restricted stock units		47				118
	Convertible preferred stock		6,857				5,571
	Diluted EPS — income allocated to common stockholders		$	278,418			147,175			$	1.89
Shares excluded from the calculation of diluted EPS:
			Year Ended December 31,
			2014			2013			2012
			(In thousands)
	Stock options		20			177			340
	Restricted stock units		7			10			5
Schedule of accumulated other comprehensive (loss) income balances
			2014											2013									2012
	Year Ended December 31,		Investment				Other				Accumulative			Investment			Other			Accumulative			Investment			Other			Foreign Currency Translation Adjustments			Accumulative
			Securities				Investments				Other			Securities			Investments			Other			Securities			Investments						Other
			Available-for-Sale								Comprehensive			Available-for-Sale						Comprehensive			Available-for-Sale									Comprehensive
											(Loss) Income									Income (Loss)												(Loss) Income
														(In thousands)
	Balance, beginning of the period		$	(30,538	)		$	79			$	(30,459	)	$	4,643		$	26		$	4,669		$	(34,848	)	$	8		$	900		$	(33,940	)
	Net unrealized gains (losses) arising during period		41,008				(97		)		40,911			(28,169		)	336			(27,833		)	42,868			31			—			42,899
	Less: reclassification adjustment for (gains) losses included in net income		(6,294		)		79				(6,215		)	(7,012		)	(283		)	(7,295		)	(439		)	(13		)	—			(452		)
	Net unrealized gains (losses)		34,714				(18		)		34,696			(35,181		)	53			(35,128		)	42,429			18			—			42,447
	Noncredit-related impairment loss on securities		—				—				—			—			—			—			(2,938		)	—			—			(2,938		)
	Foreign currency translation adjustments		—				—				—			—			—			—			—			—			(900		)	(900		)
	Balance, end of the period		$	4,176			$	61			$	4,237		$	(30,538	)	$	79		$	(30,459	)	$	4,643		$	26		$	—		$	4,669
Schedule of components of other comprehensive income (loss), reclassifications to net income by income statement line item and the related tax effects
			2014											2013									2012
	Year Ended December 31,		Before-Tax				Tax				Net-of-Tax			Before-Tax			Tax			Net-of-Tax			Before-Tax			Tax			Net-of-Tax
			Amount				Expense				Amount			Amount			Expense			Amount			Amount			Expense			Amount
							or Benefit										or Benefit									or Benefit
														(In thousands)
	Unrealized gains (losses) on investment securities available-for-sale:
	Net unrealized gains (losses) arising during period		$	70,704			$	(29,696	)		$	41,008		$	(48,567	)	$	20,398		$	(28,169	)	$	73,910		$	(31,042	)	$	42,868
	Less: reclassification adjustment for gains included in net income (1)		(10,851		)		4,557				(6,294		)	(12,089		)	5,077			(7,012		)	(757		)	318			(439		)
	Net unrealized gains (losses)		59,853				(25,139		)		34,714			(60,656		)	25,475			(35,181		)	73,153			(30,724		)	42,429
	Noncredit-related impairment loss on securities		—				—				—			—			—			—			(5,066		)	2,128			(2,938		)
	Foreign currency translation adjustments		—				—				—			—			—			—			(1,552		)	652			(900		)
	Unrealized (losses) gains on other investments:
	Net unrealized (losses) gains arising during period		(167		)		70				(97		)	579			(243		)	336			53			(22		)	31
	Less: reclassification adjustment for losses (gains) included in income (2)		136				(57		)		79			(488		)	205			(283		)	(23		)	10			(13		)
	Net unrealized (losses) gains		(31		)		13				(18		)	91			(38		)	53			30			(12		)	18
	Other comprehensive income (loss)		$	59,822			$	(25,126	)		$	34,696		$	(60,565	)	$	25,437		$	(35,128	)	$	66,565		$	(27,956	)	$	38,609
	-1	The pretax amount is reported in net gains on sales of investment securities in the consolidated statements of income.
	-2	The pretax income is reported in dividend and other investment income in the consolidated statements of income.

REGULATORY_REQUIREMENTS_Tables

REGULATORY REQUIREMENTS (Tables)	12 Months Ended
	Dec. 31, 2014
REGULATORY REQUIREMENTS
Schedule of actual and required capital amounts and ratios
		Actual				For Capital				To Be Well Capitalized
						Adequacy Purposes				Under Prompt Corrective
										Action Provisions
		Amount		Ratio		Amount		Ratio		Amount		Ratio
						($ in thousands)
	As of December 31, 2014
	Total Capital (to Risk-Weighted Assets)
	Company	$	2,753,598	12.6	%	$	1,754,519	8	%	N/A		N/A
	East West Bank	$	2,590,174	11.8	%	$	1,750,006	8	%	$	2,187,508	10	%
	Tier I Capital (to Risk-Weighted Assets)
	Company	$	2,405,452	11	%	$	877,259	4	%	N/A		N/A
	East West Bank	$	2,316,615	10.6	%	$	875,003	4	%	$	1,312,505	6	%
	Tier I Capital (to Average Assets)
	Company	$	2,405,452	8.4	%	$	1,140,045	4	%	N/A		N/A
	East West Bank	$	2,316,615	8.2	%	$	1,136,734	4	%	$	1,420,917	5	%
	As of December 31, 2013
	Total Capital (to Risk-Weighted Assets)
	Company	$	2,395,109	13.5	%	$	1,416,203	8	%	N/A		N/A
	East West Bank	$	2,262,494	12.9	%	$	1,407,944	8	%	$	1,759,931	10	%
	Tier I Capital (to Risk-Weighted Assets)
	Company	$	2,102,476	11.9	%	$	708,102	4	%	N/A		N/A
	East West Bank	$	2,041,894	11.6	%	$	703,972	4	%	$	1,055,958	6	%
	Tier I Capital (to Average Assets)
	Company	$	2,102,476	8.6	%	$	976,596	4	%	N/A		N/A
	East West Bank	$	2,041,894	8.4	%	$	973,958	4	%	$	1,217,448	5	%

SEGMENT_INFORMATION_Tables

SEGMENT INFORMATION (Tables)	12 Months Ended
	Dec. 31, 2014
SEGMENT INFORMATION
Operating results and key financial measures for operating segments
			Year Ended December 31, 2014
			Retail			Commercial			Other			Total
			Banking			Banking
			(In thousands)
	Interest and dividend income		$	378,445		$	715,075		$	60,178		$	1,153,698
	Charge for funds used		(94,162		)	(141,652		)	(47,570		)	(283,384		)
	Interest spread on funds used		284,283			573,423			12,608			870,314
	Interest expense		(48,020		)	(15,650		)	(49,150		)	(112,820		)
	Credit on funds provided		225,873			38,592			18,919			283,384
	Interest spread on funds provided		177,853			22,942			(30,231		)	170,564
	Net interest income (loss) before provision for loan losses		$	462,136		$	596,365		$	(17,623	)	$	1,040,878
	Provision for loan losses		$	14,979		$	34,179		$	—		$	49,158
	Depreciation, amortization and accretion (1)		$	14,376		$	(8,372	)	$	108,117		$	114,121
	Goodwill		$	357,207		$	112,226		$	—		$	469,433
	Income before provision for income taxes		$	166,637		$	276,601		$	(27,783	)	$	415,455
	Assets		$	7,621,808		$	15,595,862		$	5,520,379		$	28,738,049
			Year Ended December 31, 2013
			Retail			Commercial			Other			Total
			Banking			Banking
			(In thousands)
	Interest and dividend income		$	374,818		$	627,118		$	66,749		$	1,068,685
	Charge for funds used		(86,552		)	(116,161		)	(18,244		)	(220,957		)
	Interest spread on funds used		288,266			510,957			48,505			847,728
	Interest expense		(47,287		)	(15,185		)	(50,020		)	(112,492		)
	Credit on funds provided		173,194			29,262			18,501			220,957
	Interest spread on funds provided		125,907			14,077			(31,519		)	108,465
	Net interest income before provision for loan losses		$	414,173		$	525,034		$	16,986		$	956,193
	Provision for loan losses		$	10,911		$	11,453		$	—		$	22,364
	Depreciation, amortization and accretion (1)		$	19,865		$	8,120		$	69,125		$	97,110
	Goodwill		$	320,566		$	16,872		$	—		$	337,438
	Income before provision for income taxes		$	123,876		$	272,369		$	29,605		$	425,850
	Assets		$	7,820,191		$	11,545,405		$	5,364,472		$	24,730,068
			Year Ended December 31, 2012
			Retail			Commercial			Other			Total
			Banking			Banking
			(In thousands)
	Interest and dividend income		$	356,244		$	617,041		$	77,810		$	1,051,095
	Charge for funds used		(85,811		)	(118,688		)	44,407			(160,092		)
	Interest spread on funds used		270,433			498,353			122,217			891,003
	Interest expense		(57,401		)	(23,226		)	(51,541		)	(132,168		)
	Credit on funds provided		130,713			13,138			16,241			160,092
	Interest spread on funds provided		73,312			(10,088		)	(35,300		)	27,924
	Net interest income before provision for loan losses		$	343,745		$	488,265		$	86,917		$	918,927
	Provision for loan losses		$	28,729		$	36,455		$	—		$	65,184
	Depreciation, amortization and accretion (1)		$	12,869		$	(13,277	)	$	44,159		$	43,751
	Goodwill		$	320,566		$	16,872		$	—		$	337,438
	Income before provision for income taxes		$	74,836		$	266,168		$	84,588		$	425,592
	Assets		$	6,552,217		$	10,421,160		$	5,562,733		$	22,536,110
	-1	Includes amortization and accretion related to the FDIC indemnification asset.

PARENT_COMPANY_CONDENSED_FINAN1

PARENT COMPANY CONDENSED FINANCIAL STATEMENTS (Tables)	12 Months Ended
	Dec. 31, 2014
PARENT COMPANY CONDENSED FINANCIAL STATEMENTS
Condensed Balance Sheets
		December 31,
		2014			2013
		(In thousands)
	ASSETS
	Cash and cash equivalents	$	211,053		$	79,934
	Investment securities available-for-sale, at fair value	8,370			69,796
	Investment in subsidiaries	2,841,684			2,400,937
	Other investments	41,054			21,371
	Other assets	22,474			37,037
	TOTAL	$	3,124,635		$	2,609,075
	LIABILITIES AND STOCKHOLDERS’ EQUITY
	Long-term debt	$	225,848		$	226,868
	Other liabilities	48,219			17,982
	Total liabilities	274,067			244,850
	STOCKHOLDERS’ EQUITY
	Common stock, $0.001 par value, 200,000,000 shares authorized; 163,772,218 and 163,098,008 shares issued in 2014 and 2013, respectively; 143,582,229 and 137,630,896 shares outstanding in 2014 and 2013, respectively.	164			163
	Additional paid in capital	1,677,767			1,571,670
	Retained earnings	1,598,598			1,360,130
	Treasury stock, at cost — 20,189,989 shares in 2014 and 25,467,112 shares in 2013	(430,198		)	(537,279		)
	Accumulated other comprehensive income (loss), net of tax	4,237			(30,459		)
	Total stockholders’ equity	2,850,568			2,364,225
	TOTAL	$	3,124,635		$	2,609,075
Condensed Statements of Income
		Year Ended December 31,
		2014			2013			2012
		(In thousands)
	Dividends from subsidiaries	$	111,701		$	319,085		$	324,094
	Other income	7,414			821			2
	Total income	119,115			319,906			324,096
	Interest expense	4,823			3,436			3,092
	Compensation and net occupancy reimbursement to subsidiary	4,039			3,662			2,573
	Other expense	50,280			12,677			1,309
	Total expense	59,142			19,775			6,974
	Income before income taxes and equity in undistributed income of subsidiaries	59,973			300,131			317,122
	Income tax benefit	80,674			22,885			2,892
	Equity in undistributed income (loss) of subsidiaries	201,836			(27,971		)	(38,364		)
	Net income	$	342,483		$	295,045		$	281,650
Condensed Statements of Cash Flows
		Year Ended December 31,
		2014			2013			2012
		(In thousands)
	CASH FLOWS FROM OPERATING ACTIVITIES
	Net income	$	342,483		$	295,045		$	281,650
	Adjustments to reconcile net income to net cash provided by operating activities:
	Equity in undistributed income of subsidiaries	(314,225		)	(291,659		)	(285,636		)
	Depreciation and amortization	46,365			8,806			445
	Gains on sales of investment securities and other investments	(4,357		)	(161		)	—
	Tax benefit from stock compensation plans, net	(6,513		)	(5,522		)	(462		)
	Net change in other assets	186,232			293,153			322,361
	Net change in other liabilities	150			(41		)	(25		)
	Net cash provided by operating activities	250,135			299,621			318,333
	CASH FLOWS FROM INVESTING ACTIVITIES
	Purchases of:
	Investment securities available-for-sale	(9,000		)	(69,986		)	—
	Equity investments	(53,071		)	(12,970		)	(234		)
	Proceeds from sale of:
	Investment securities available-for-sale	74,002			—			—
	Net cash provided by (used in) investing activities	11,931			(82,956		)	(234		)
	CASH FLOWS FROM FINANCING ACTIVITIES
	Payments for:
	Repayment of long-term debt	(30,310		)	(10,310		)	—
	Repurchase of vested shares due to employee tax liability	(10,326		)	(13,833		)	(3,012		)
	Cash dividends on preferred stock	—			(3,428		)	(6,857		)
	Cash dividends on common stock	(103,618		)	(82,862		)	(57,361		)
	Repurchase of shares of treasury stock pursuant to the Stock Repurchase Plan	—			(199,992		)	(199,950		)
	Proceeds from:
	Increase in long-term borrowings	—			100,000			—
	Issuance of common stock pursuant to various stock plans and agreements	6,794			3,683			3,821
	Tax benefit from stock compensation plans, net	6,513			5,522			462
	Net cash used in financing activities	(130,947		)	(201,220		)	(262,897		)
	Net increase in cash and cash equivalents	131,119			15,445			55,202
	Cash and cash equivalents, beginning of year	79,934			64,489			9,287
	Cash and cash equivalents, end of year	$	211,053		$	79,934		$	64,489
	Supplemental Cash Flow Information:
	Cash paid during the year for:
	Interest	$	4,462		$	3,292		$	3,112
	Noncash financing activities:
	Conversion of preferred stock to common stock	$	—		$	83,027		$	—
	Issuance of common stock related to acquisition	$	190,830		$	—		$	—

QUARTERLY_FINANCIAL_INFORMATIO1

QUARTERLY FINANCIAL INFORMATION (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2014
QUARTERLY FINANCIAL INFORMATION (unaudited)
Schedule of quarterly financial information (unaudited)
		Quarters Ended
		December 31,			September 30,			June 30,			March 31,
		(In thousands, except per share data)
	2014
	Interest and dividend income	$	287,135		$	285,948		$	294,442		$	286,173
	Interest expense	27,647			28,974			27,992			28,207
	Net interest income before provision for loan losses	259,488			256,974			266,450			257,966
	Provision for loan losses on non-covered loans	19,671			7,556			8,944			7,954
	(Reversal of) provision for loan losses on covered loans	(671		)	7,669			(944		)	(1,021		)
	Net interest income after provision for loan losses	240,488			241,749			258,450			251,033
	Noninterest income (loss)	7,805			10,342			(14,945		)	(14,916		)
	Noninterest expense	135,246			176,979			127,899			124,427
	Income before taxes	113,047			75,112			115,606			111,690
	Income tax provision (benefit)	20,049			(13,644		)	31,618			34,949
	Net income	$	92,998		$	88,756		$	83,988		$	76,741
	Basic earnings per share	$	0.65		$	0.62		$	0.59		$	0.54
	Diluted earnings per share	$	0.65		$	0.62		$	0.58		$	0.54
	2013
	Interest and dividend income	$	293,203		$	281,706		$	255,353		$	238,423
	Interest expense	28,195			27,456			27,709			29,132
	Net interest income before provision for loan losses	265,008			254,250			227,644			209,291
	Provision for (reversal of) loan losses on non-covered loans	6,286			4,535			8,277			(762		)
	(Reversal of) provision for loan losses on covered loans	(820		)	(964		)	723			5,089
	Net interest income after provision for loan losses	259,542			250,679			218,644			204,964
	Noninterest loss	(36,594		)	(41,421		)	(12,354		)	(2,099		)
	Noninterest expense	124,384			100,352			94,420			96,355
	Income before taxes	98,564			108,906			111,870			106,510
	Income tax provision	22,782			35,749			37,855			34,419
	Net income	75,782			73,157			74,015			72,091
	Preferred stock dividends	—			—			1,714			1,714
	Net income available to common stockholders	$	75,782		$	73,157		$	72,301		$	70,377
	Basic earnings per share	$	0.55		$	0.53		$	0.52		$	0.51
	Diluted earnings per share	$	0.55		$	0.53		$	0.52		$	0.5

SUMMARY_OF_OPERATIONS_AND_SIGN3

SUMMARY OF OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
	item
	trust
Operations summary
Number of banking locations	130
Principles of Consolidation
Number of wholly owned subsidiaries that are statutory business trusts ("the Trusts")	6
Cash and Cash Equivalents
Minimum term of cash and cash equivalients investments	1 day
Maximum term of cash and cash equivalients investments	90 days
Short-term investments
Minimum term of maturities of other short-term investments	90 days
Maximum term of maturities of other short-term investments	1 year
Securities purchased under resale agreements ("Resale Agreements")
Minimum term of resale agreement to be classified as cash and cash equivalents	1 day
Maximum term of resale agreement to be classified as cash and cash equivalents	90 days
Loans receivable
Number of past due days for the loans receivable to be placed on nonaccrual status	90 days
Troubled debt restructurings
Period for which restructured loans remains on nonaccrual status, to demonstrate that the borrower can perform under the restructured terms	6 months
Other real estate owned
Maximum period of foreclosure within which sale of real estate owned will be recorded at fair value less cost of sales	3 months
FDIC percentage of reimbursement under shared loss agreements
FDIC percentage of reimbursement under shared loss agreements	80.00%	80.00%	80.00%
Percentage of company's liability for losses under shared loss agreements.	20.00%	20.00%	20.00%
Greater China
Operations summary
Number of full-service branches	5
Number of representative offices	5
Shanghai
Operations summary
Number of full-service branches	2
Shanghai Pilot Free Trade Zone
Operations summary
Number of full-service branches	1

SUMMARY_OF_OPERATIONS_AND_SIGN4

SUMMARY OF OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES (Details 2) (Customer Relationships)	12 Months Ended
	Dec. 31, 2014
Minimum
Goodwill and other intangible assets
Projected useful life	7 years
Maximum
Goodwill and other intangible assets
Projected useful life	15 years

SUMMARY_OF_OPERATIONS_AND_SIGN5

SUMMARY OF OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES (Details 3)	12 Months Ended
	Dec. 31, 2014
Long-Term Debt
Number of statutory business trusts	6
Building and Building Improvements
Premises and equipment
Estimated useful life	25 years
Furniture, fixtures and equipment | Minimum
Premises and equipment
Estimated useful life	3 years
Furniture, fixtures and equipment | Maximum
Premises and equipment
Estimated useful life	7 years

BUSINESS_COMBINATION_Details

BUSINESS COMBINATION (Details) (USD $)	12 Months Ended	0 Months Ended		3 Months Ended	12 Months Ended
	Dec. 31, 2014	Jan. 17, 2014	Jan. 17, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
		item
Business combination
Consideration transferred in the acquisition (in shares)	5,583,093
Issuance of 5,583,093 shares pursuant to MetroCorp acquisition	$190,830,000
Goodwill recorded as a result of the business combination	469,433,000			469,433,000	337,438,000	337,438,000
MetroCorp
Business combination
Number of branches		19
Number of subsidiaries		2
Percentage of purchase consideration satisfied in stock			66.67%
Percentage of purchase consideration satisfied in cash			33.33%
Fair value of the consideration transferred			291,400,000
Consideration transferred in the acquisition (in shares)			5,583,093
Issuance of 5,583,093 shares pursuant to MetroCorp acquisition			190,800,000
Consideration transferred in cash			89,400,000
Additional cash given to acquiree's stock option holders as part of consideration transferred			2,400,000
Amount given for warrant's assumed as part of consideration transferred			8,800,000
Goodwill recorded as a result of the business combination	132,000,000	121,000,000	121,000,000	132,000,000
Fair value of assets acquired		1,700,000,000	1,700,000,000
Cash and due from banks		230,300,000	230,300,000
Investment securities available for sale		64,300,000	64,300,000
FHLB stock		2,700,000	2,700,000
Loans receivable		1,190,000,000	1,190,000,000
Fixed assets		8,600,000	8,600,000
Premiums on deposits acquired		8,600,000	8,600,000
OREO		9,400,000	9,400,000
Bank owned life insurance		30,000,000	30,000,000
Deferred tax assets		13,000,000	13,000,000
Other assets		16,700,000	16,700,000
Fair value of liabilities acquired		1,410,000,000	1,410,000,000
Deposits		1,320,000,000	1,320,000,000
FHLB advances		10,000,000	10,000,000
Repurchase agreements		25,900,000	25,900,000
Junior subordinated debts		29,100,000	29,100,000
Other liabilities		22,700,000	22,700,000
Information relating to the acquisition of MetroCorp	11,000,000			11,000,000
Pro forma information
Net interest income and noninterest loss	1,028,796,000				934,207,000
Net income after tax	338,730,000				299,625,000
MetroCorp | Bank Owned Life Insurance
Business combination
Information relating to the acquisition of MetroCorp	700,000			700,000
MetroCorp | Additional Tax Adjustments
Business combination
Information relating to the acquisition of MetroCorp	$10,300,000			$10,300,000

FAIR_VALUE_MEASUREMENT_AND_FAI2

FAIR VALUE MEASUREMENT AND FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Investment securities available-for-sale
Total investment securities available-for-sale	$2,626,365		$2,733,797
U.S. Treasury securities
Investment securities available-for-sale
Total investment securities available-for-sale	873,435		491,632
U.S. government agency and U.S. government sponsored enterprise debt securities
Investment securities available-for-sale
Total investment securities available-for-sale	311,024		394,323
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities
Investment securities available-for-sale
Total investment securities available-for-sale	141,420		178,870
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities
Investment securities available-for-sale
Total investment securities available-for-sale	791,088		885,237
Municipal securities
Investment securities available-for-sale
Total investment securities available-for-sale	250,448		280,979
Other residential mortgage-backed securities | Investment grade
Investment securities available-for-sale
Total investment securities available-for-sale	53,918	[1]	46,327	[1]
Other commercial mortgage-backed securities | Investment grade
Investment securities available-for-sale
Total investment securities available-for-sale	34,053	[1]	51,617	[1]
Corporate debt securities | Investment grade
Investment securities available-for-sale
Total investment securities available-for-sale	115,182	[1]	309,995	[1]
Corporate debt securities | Non-investment grade
Investment securities available-for-sale
Total investment securities available-for-sale	14,681	[1]	15,101	[1]
Other securities
Investment securities available-for-sale
Total investment securities available-for-sale	41,116		79,716
Fair Value, Measurements, Recurring | Fair Value Measurements
Investment securities available-for-sale
Total investment securities available-for-sale	2,626,365		2,733,797
Fair Value, Measurements, Recurring | Fair Value Measurements | Foreign exchange options
Derivative
Derivative assets	6,136		6,290
Fair Value, Measurements, Recurring | Fair Value Measurements | Interest rate swaps and caps
Derivative
Derivative assets	41,534		28,078
Derivative liabilities	-41,779		-26,352
Fair Value, Measurements, Recurring | Fair Value Measurements | Foreign exchange contracts
Derivative
Derivative assets	8,123		6,181
Derivative liabilities	-9,171		-3,349
Fair Value, Measurements, Recurring | Fair Value Measurements | Interest rate swaps on certificates of deposits
Derivative
Derivative liabilities	-9,922		-16,906
Fair Value, Measurements, Recurring | Fair Value Measurements | Embedded derivatives liabilities
Derivative
Derivative liabilities	-3,392		-3,655
Fair Value, Measurements, Recurring | Fair Value Measurements | U.S. Treasury securities
Investment securities available-for-sale
Total investment securities available-for-sale	873,435		491,632
Fair Value, Measurements, Recurring | Fair Value Measurements | U.S. government agency and U.S. government sponsored enterprise debt securities
Investment securities available-for-sale
Total investment securities available-for-sale	311,024		394,323
Fair Value, Measurements, Recurring | Fair Value Measurements | U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities
Investment securities available-for-sale
Total investment securities available-for-sale	141,420		178,870
Fair Value, Measurements, Recurring | Fair Value Measurements | U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities
Investment securities available-for-sale
Total investment securities available-for-sale	791,088		885,237
Fair Value, Measurements, Recurring | Fair Value Measurements | Municipal securities
Investment securities available-for-sale
Total investment securities available-for-sale	250,448		280,979
Fair Value, Measurements, Recurring | Fair Value Measurements | Other residential mortgage-backed securities | Investment grade
Investment securities available-for-sale
Total investment securities available-for-sale	53,918		46,327
Fair Value, Measurements, Recurring | Fair Value Measurements | Other commercial mortgage-backed securities | Investment grade
Investment securities available-for-sale
Total investment securities available-for-sale	34,053		51,617
Fair Value, Measurements, Recurring | Fair Value Measurements | Corporate debt securities | Investment grade
Investment securities available-for-sale
Total investment securities available-for-sale	115,182		309,995
Fair Value, Measurements, Recurring | Fair Value Measurements | Corporate debt securities | Non-investment grade
Investment securities available-for-sale
Total investment securities available-for-sale	14,681		15,101
Fair Value, Measurements, Recurring | Fair Value Measurements | Other securities
Investment securities available-for-sale
Total investment securities available-for-sale	41,116		79,716
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Investment securities available-for-sale
Total investment securities available-for-sale	905,540		491,632
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Treasury securities
Investment securities available-for-sale
Total investment securities available-for-sale	873,435		491,632
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other securities
Investment securities available-for-sale
Total investment securities available-for-sale	32,105
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Investment securities available-for-sale
Total investment securities available-for-sale	1,714,297		2,235,794
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Foreign exchange options
Derivative
Derivative assets	6,136		6,290
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Interest rate swaps and caps
Derivative
Derivative assets	41,534		28,078
Derivative liabilities	-41,779		-26,352
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Foreign exchange contracts
Derivative
Derivative assets	8,123		6,181
Derivative liabilities	-9,171		-3,349
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Interest rate swaps on certificates of deposits
Derivative
Derivative liabilities	-9,922		-16,906
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S. government agency and U.S. government sponsored enterprise debt securities
Investment securities available-for-sale
Total investment securities available-for-sale	311,024		394,323
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities
Investment securities available-for-sale
Total investment securities available-for-sale	141,420		178,870
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities
Investment securities available-for-sale
Total investment securities available-for-sale	791,088		885,237
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Municipal securities
Investment securities available-for-sale
Total investment securities available-for-sale	250,448		280,979
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Other residential mortgage-backed securities | Investment grade
Investment securities available-for-sale
Total investment securities available-for-sale	53,918		46,327
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Other commercial mortgage-backed securities | Investment grade
Investment securities available-for-sale
Total investment securities available-for-sale	34,053		51,617
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Corporate debt securities | Investment grade
Investment securities available-for-sale
Total investment securities available-for-sale	115,182		309,995
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Corporate debt securities | Non-investment grade
Investment securities available-for-sale
Total investment securities available-for-sale	8,153		8,730
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Other securities
Investment securities available-for-sale
Total investment securities available-for-sale	9,011		79,716
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Investment securities available-for-sale
Total investment securities available-for-sale	6,528		6,371
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Embedded derivatives liabilities
Derivative
Derivative liabilities	-3,392		-3,655
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Corporate debt securities | Non-investment grade
Investment securities available-for-sale
Total investment securities available-for-sale	$6,528		$6,371
[1]	Investment securities rated BBB- or higher by S&P, or Baa3 or higher by Moody are considered investment grade. Conversely, investment securities rated below BBB- by S&P, or below Baa3 by Moody are considered non-investment grade.

FAIR_VALUE_MEASUREMENT_AND_FAI3

FAIR VALUE MEASUREMENT AND FAIR VALUE OF FINANCIAL INSTRUMENTS (Details 2) (Fair Value, Measurements, Recurring, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Embedded Derivative Liabilities
Reconciliation of the beginning and ending balances for major liability categories measured at fair value on a recurring basis using significant unobservable inputs (Level 3)
Beginning balance	($3,655)		($3,052)		($2,634)
Total gains or (losses) for the period:
Included in earnings	263	[1]	-603	[1]	-418	[1]
Purchases, issues, sales, settlements
Closing balance	-3,392		-3,655		-3,052
Changes in unrealized gains (losses) included in earnings relating to assets and liabilities held at period-end	-263		603		418
Corporate debt securities | Non-investment grade
Reconciliation of the beginning and ending balances for major asset categories measured at fair value on a recurring basis using significant unobservable inputs (Level 3)
Beginning balance	6,371		4,800		2,235
Total gains or (losses) for the period:
Included in earnings	802	[1]			-99	[1]
Included in other comprehensive income (unrealized)	2,326	[2]	1,653	[2]	2,711	[2]
Purchases, issues, sales, settlements
Sales	-2,595
Settlements	-376		-82		-47
Closing balance	6,528		6,371		4,800
Purchases, issues, sales, settlements
Changes in unrealized gains (losses) included in earnings relating to assets and liabilities held at period-end					$99
[1]	Realized gains or losses of corporate debt securities and embedded derivative liabilities are included in net gains on sales of investment securities and other operating expense, respectively, in the consolidated statements of income.
[2]	Unrealized gains or losses on investment securities are reported in other comprehensive income (loss), net of tax, in the consolidated statements of comprehensive income.

FAIR_VALUE_MEASUREMENT_AND_FAI4

FAIR VALUE MEASUREMENT AND FAIR VALUE OF FINANCIAL INSTRUMENTS (Details 3) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Quantitative information
Investment securities available-for-sale	2,626,365		2,733,797
Corporate debt securities | Non-investment grade
Quantitative information
Investment securities available-for-sale	14,681	[1]	15,101	[1]
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Quantitative information
Investment securities available-for-sale	6,528		6,371
Fair Value, Measurements, Recurring | Embedded Derivative Liabilities | Discounted cash flow | Significant Unobservable Inputs (Level 3)
Quantitative information
Derivative liabilities	-3,392		-3,655
Fair Value, Measurements, Recurring | Embedded Derivative Liabilities | Discounted cash flow | Significant Unobservable Inputs (Level 3) | Minimum
Quantitative information
Credit risk	0.12%		0.18%
Fair Value, Measurements, Recurring | Embedded Derivative Liabilities | Discounted cash flow | Significant Unobservable Inputs (Level 3) | Maximum
Quantitative information
Credit risk	0.14%		0.21%
Fair Value, Measurements, Recurring | Embedded Derivative Liabilities | Discounted cash flow | Significant Unobservable Inputs (Level 3) | Weighted Average
Quantitative information
Credit risk	0.13%		0.20%
Fair Value, Measurements, Recurring | Corporate debt securities | Non-investment grade | Significant Unobservable Inputs (Level 3)
Quantitative information
Investment securities available-for-sale	6,528		6,371
Fair Value, Measurements, Recurring | Corporate debt securities | Non-investment grade | Discounted cash flow | Significant Unobservable Inputs (Level 3)
Quantitative information
Investment securities available-for-sale	6,528		6,371
Loss severity	85.00%		85.00%
Fair Value, Measurements, Recurring | Corporate debt securities | Non-investment grade | Discounted cash flow | Significant Unobservable Inputs (Level 3) | Minimum
Quantitative information
Constant prepayment rate	0.00%		0.00%
Constant default rate	0.75%		0.75%
Discount margin	4.50%		6.50%
Fair Value, Measurements, Recurring | Corporate debt securities | Non-investment grade | Discounted cash flow | Significant Unobservable Inputs (Level 3) | Maximum
Quantitative information
Constant prepayment rate	1.00%		1.00%
Constant default rate	1.20%		1.20%
Discount margin	7.50%		11.50%
Fair Value, Measurements, Recurring | Corporate debt securities | Non-investment grade | Discounted cash flow | Significant Unobservable Inputs (Level 3) | Weighted Average
Quantitative information
Constant prepayment rate	0.73%		0.74%
Constant default rate	0.87%		0.87%
Loss severity	85.00%		85.00%
Discount margin	6.94%		9.97%
[1]	Investment securities rated BBB- or higher by S&P, or Baa3 or higher by Moody are considered investment grade. Conversely, investment securities rated below BBB- by S&P, or below Baa3 by Moody are considered non-investment grade.

FAIR_VALUE_MEASUREMENT_AND_FAI5

FAIR VALUE MEASUREMENT AND FAIR VALUE OF FINANCIAL INSTRUMENTS (Details 4) (Fair Value, Measurements, Nonrecurring, USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value Measurements
Fair Value, Assets Measured on a Nonrecurring Basis
Non-covered loans	$67,811	$57,751
Fair Value Measurements | Non-covered OREO
Fair Value, Assets Measured on a Nonrecurring Basis
Non-covered OREO	15,735	13,031
Fair Value Measurements | Covered OREO
Fair Value, Assets Measured on a Nonrecurring Basis
Covered OREO	1,786	17,284
Fair Value Measurements | CRE
Fair Value, Assets Measured on a Nonrecurring Basis
Non-covered loans	26,089	29,559
Fair Value Measurements | C&I
Fair Value, Assets Measured on a Nonrecurring Basis
Non-covered loans	16,581	15,120
Fair Value Measurements | Residential
Fair Value, Assets Measured on a Nonrecurring Basis
Non-covered loans	25,034	12,791
Fair Value Measurements | Consumer
Fair Value, Assets Measured on a Nonrecurring Basis
Non-covered loans	107	281
Significant Unobservable Inputs (Level 3)
Fair Value, Assets Measured on a Nonrecurring Basis
Non-covered loans	67,811	57,751
Significant Unobservable Inputs (Level 3) | Non-covered OREO
Fair Value, Assets Measured on a Nonrecurring Basis
Non-covered OREO	15,735	13,031
Significant Unobservable Inputs (Level 3) | Covered OREO
Fair Value, Assets Measured on a Nonrecurring Basis
Covered OREO	1,786	17,284
Significant Unobservable Inputs (Level 3) | CRE
Fair Value, Assets Measured on a Nonrecurring Basis
Non-covered loans	26,089	29,559
Significant Unobservable Inputs (Level 3) | C&I
Fair Value, Assets Measured on a Nonrecurring Basis
Non-covered loans	16,581	15,120
Significant Unobservable Inputs (Level 3) | Residential
Fair Value, Assets Measured on a Nonrecurring Basis
Non-covered loans	25,034	12,791
Significant Unobservable Inputs (Level 3) | Consumer
Fair Value, Assets Measured on a Nonrecurring Basis
Non-covered loans	$107	$281

FAIR_VALUE_MEASUREMENT_AND_FAI6

FAIR VALUE MEASUREMENT AND FAIR VALUE OF FINANCIAL INSTRUMENTS (Details 5) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Covered OREO
Percentage of company's liability for losses under shared loss agreements	20.00%		20.00%		20.00%
Percentage of eligible losses for which the FDIC is obligated to reimburse the Company	80.00%		80.00%		80.00%
Fair Value, Measurements, Nonrecurring
Fair Value, Assets Measured on a Nonrecurring Basis
Increase (decrease) in value of assets	-7,035		-18,875		-28,012
Company's liability for losses under shared loss agreements	205		675		2,200
Fair Value, Measurements, Nonrecurring | Non-covered OREO
Fair Value, Assets Measured on a Nonrecurring Basis
Increase (decrease) in value of assets	-1,573		-1,438		-5,122
Fair Value, Measurements, Nonrecurring | Covered OREO
Fair Value, Assets Measured on a Nonrecurring Basis
Increase (decrease) in value of assets	-1,027	[1]	-3,376	[1]	-11,183	[1]
Fair Value, Measurements, Nonrecurring | CRE
Fair Value, Assets Measured on a Nonrecurring Basis
Increase (decrease) in value of assets	2,196		-4,250		-8,405
Fair Value, Measurements, Nonrecurring | C&I
Fair Value, Assets Measured on a Nonrecurring Basis
Increase (decrease) in value of assets	-9,169		-13,135		-14,540
Fair Value, Measurements, Nonrecurring | Residential
Fair Value, Assets Measured on a Nonrecurring Basis
Increase (decrease) in value of assets	-61		-1,378		-4,803
Fair Value, Measurements, Nonrecurring | Consumer
Fair Value, Assets Measured on a Nonrecurring Basis
Increase (decrease) in value of assets	-1		-112		-264
[1]	Covered OREO results from the WFIB and UCB FDIC-assisted acquisitions for which the Company entered into shared-loss agreements with the FDIC whereby the FDIC will reimburse the Company for 80% of eligible losses. As such, the Company's liability for losses is 20% of the $1.0 million in losses, or $205 thousand, and 20% of the $3.4 million in losses, or $675 thousand, and 20% of the $11.2 million in losses, or $2.2 million for the years ended December 31, 2014, 2013, and 2012, respectively.

FAIR_VALUE_MEASUREMENT_AND_FAI7

FAIR VALUE MEASUREMENT AND FAIR VALUE OF FINANCIAL INSTRUMENTS (Details 6) (Fair Value, Measurements, Nonrecurring, Significant Unobservable Inputs (Level 3), USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Quantitative information
Non-covered impaired loans	67,811		57,751
Non-covered impaired loans | Discounted cash flow
Quantitative information
Non-covered impaired loans	11,499
Non-covered impaired loans | Discounted cash flow | Minimum
Quantitative information
Discount rate (as a percent)	0.00%
Non-covered impaired loans | Discounted cash flow | Maximum
Quantitative information
Discount rate (as a percent)	81.00%
Non-covered impaired loans | Discounted cash flow | Weighted Average
Quantitative information
Discount rate (as a percent)	49.00%
Non-covered impaired loans | Market comparables
Quantitative information
Non-covered impaired loans	56,312		57,751
Non-covered impaired loans | Market comparables | Minimum
Quantitative information
Discount rate (as a percent)	0.00%	[1]	0.00%	[1]
Non-covered impaired loans | Market comparables | Maximum
Quantitative information
Discount rate (as a percent)	100.00%	[1]	100.00%	[1]
Non-covered impaired loans | Market comparables | Weighted Average
Quantitative information
Discount rate (as a percent)	4.00%	[1]	13.00%	[1]
Non-covered OREO
Quantitative information
Non-covered OREO	15,735		13,031
Non-covered OREO | Appraisal
Quantitative information
Non-covered OREO	15,735		13,031
Selling cost (as a percent)	8.00%		8.00%
Non-covered OREO | Appraisal | Weighted Average
Quantitative information
Selling cost (as a percent)	8.00%		8.00%
Covered OREO
Quantitative information
Covered OREO	1,786		17,284
[1]	Discount rate is adjusted for factors such as liquidation cost of collateral and selling cost.

FAIR_VALUE_MEASUREMENT_AND_FAI8

FAIR VALUE MEASUREMENT AND FAIR VALUE OF FINANCIAL INSTRUMENTS (Details 7) (USD $)	Dec. 31, 2014	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Financial Assets:
Cash and cash equivalents	$1,039,885	$895,820		$1,323,106	$1,431,185
Short-term Investments	338,714	257,473
Securities purchased under resale agreements	1,225,000	1,300,000	[1]
Loans held for sale	45,950	204,970
Loans receivable, net	21,468,270	17,600,613
Investment in Federal Home Loan Bank stock	31,239	62,330
Investment in Federal Reserve Bank stock	54,451	48,333
Financial Liabilities:
Demand, savings and money market deposits	17,896,035	14,588,570
Time Deposits	6,112,739	5,824,348
Federal Home Loan Bank advances	317,241	315,092
Securities sold under repurchase agreements	795,000	995,000
Long-term debt	225,848	226,868
Quoted Prices in Active Markets for Identical Assets (Level 1)
Financial Assets:
Cash and cash equivalents	1,039,885	895,820
Significant Other Observable Inputs (Level 2)
Financial Assets:
Short-term Investments	338,714	257,473
Securities purchased under resale agreements	1,191,060	1,279,406
Loans held for sale	45,950	212,469
Investment in Federal Home Loan Bank stock	31,239	62,330
Investment in Federal Reserve Bank stock	54,451	48,333
Accrued interest receivable	88,303	116,314
Financial Liabilities:
Demand, savings and money market deposits	17,896,035	14,588,570
Federal Home Loan Bank advances	336,302	308,521
Securities sold under repurchase agreements	870,434	1,134,774
Accrued interest payable	11,303	11,178
Long-term debt	205,777	184,415
Significant Unobservable Inputs (Level 3)
Financial Assets:
Loans receivable, net	20,997,379	16,741,674
Financial Liabilities:
Time Deposits	6,095,217	5,791,659
Carrying Amount
Financial Assets:
Cash and cash equivalents	1,039,885	895,820
Short-term Investments	338,714	257,473
Securities purchased under resale agreements	1,225,000	1,300,000
Loans held for sale	45,950	204,970
Loans receivable, net	21,468,270	17,600,613
Investment in Federal Home Loan Bank stock	31,239	62,330
Investment in Federal Reserve Bank stock	54,451	48,333
Accrued interest receivable	88,303	116,314
Financial Liabilities:
Demand, savings and money market deposits	17,896,035	14,588,570
Time Deposits	6,112,739	5,824,348
Federal Home Loan Bank advances	317,241	315,092
Securities sold under repurchase agreements	795,000	995,000
Accrued interest payable	11,303	11,178
Long-term debt	225,848	226,868
Fair Value Measurements
Financial Assets:
Cash and cash equivalents	1,039,885	895,820
Short-term Investments	338,714	257,473
Securities purchased under resale agreements	1,191,060	1,279,406
Loans held for sale	45,950	212,469
Loans receivable, net	20,997,379	16,741,674
Investment in Federal Home Loan Bank stock	31,239	62,330
Investment in Federal Reserve Bank stock	54,451	48,333
Accrued interest receivable	88,303	116,314
Financial Liabilities:
Demand, savings and money market deposits	17,896,035	14,588,570
Time Deposits	6,095,217	5,791,659
Federal Home Loan Bank advances	336,302	308,521
Securities sold under repurchase agreements	870,434	1,134,774
Accrued interest payable	11,303	11,178
Long-term debt	$205,777	$184,415
[1]	Of the $1.40 billion resale agreements as of December 31, 2013, $100.0 million was recorded in cash and cash equivalents and $1.3 billion was recorded in securities under resale agreements in the consolidated balance sheet.

FAIR_VALUE_MEASUREMENT_AND_FAI9

FAIR VALUE MEASUREMENT AND FAIR VALUE OF FINANCIAL INSTRUMENTS (Details 8)	12 Months Ended
	Dec. 31, 2014
	item
Valuation Methodologies
Maximum Term of Maturity for Securities Purchased under Resale Agreements to be Included in Cash and Cash Equivalents	90 days
Term of Maturity that Securities Purchased under Resale Agreements Must Exceed to be Included in Certain Fair Value Calculations	90 days
Percentage of total available-for-sale securities represented by Level 3 available-for-sale securities, maximum	1.00%
Minimum number of quoted market prices traditionally used in determining fair value of level 3 available-for-sale securities	2
Foreign exchange options
Valuation Methodologies
Term of contracts	5 years

CASH_AND_CASH_EQUIVALENTS_AND_2

CASH AND CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Composition of cash and cash equivalents
Cash and amounts due from banks	$944,118,000	$693,387,000
Cash equivalents:
Money market funds		605,000
Other short-term investments	95,767,000	201,828,000
Total cash and cash equivalents	1,039,885,000	895,820,000	1,323,106,000	1,431,185,000
Short-term investments
Short-term investments	338,714,000	257,473,000
Interest-bearing deposits in other institutions	$50,200,000	$60,300,000

SECURITIES_PURCHASED_UNDER_RES1

SECURITIES PURCHASED UNDER RESALE AGREEMENTS AND SOLD UNDER REPURCHASE AGREEMENTS (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Resale agreements
Total	$1,425,000,000	$1,400,000,000
Maturities in 2015	875,000,000
Maturities in 2016	0
Maturities in 2017	0
Maturities in 2018	50,000,000
Maturities in 2019	0
Maturities in 2020 and thereafter	$500,000,000
Weighted average interest rates	1.55%	1.44%

SECURITIES_PURCHASED_UNDER_RES2

SECURITIES PURCHASED UNDER RESALE AGREEMENTS AND SOLD UNDER REPURCHASE AGREEMENTS (Details 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Amount of securities sold under repurchase agreements
Total	$995,000	$995,000
Interest rate on securities sold under repurchase agreements
Total (as a percent)	3.70%	4.06%
Maturities in 2015
Amount of securities sold under repurchase agreements
Total	245,000
Maturities in 2016
Amount of securities sold under repurchase agreements
Total	250,000
Maturities in 2017
Amount of securities sold under repurchase agreements
Total	50,000
Maturities in 2018
Amount of securities sold under repurchase agreements
Total	0
Maturities in 2019
Amount of securities sold under repurchase agreements
Total	0
Maturities in 2020 and thereafter
Amount of securities sold under repurchase agreements
Total	$450,000

SECURITIES_PURCHASED_UNDER_RES3

SECURITIES PURCHASED UNDER RESALE AGREEMENTS AND SOLD UNDER REPURCHASE AGREEMENTS (Details 3) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Assets, Resale Agreements
Gross Amounts of Recognized Assets	$1,425,000,000	$1,400,000,000
Gross Amounts Offset on the Consolidated Balance Sheet	-200,000,000
Net Amounts of Assets Presented	1,225,000,000	1,300,000,000	[1]
Gross Amounts Not Offset in the Consolidated Balance Sheets
Financial Instruments	-425,000,000	-495,000,000
Collateral Received	-797,172,000	-905,000,000
Net Amount	2,828,000
Liabilities, Repurchase Agreements
Gross Amounts of Recognized Liabilities	995,000,000	995,000,000
Gross Amounts Offset on the Consolidated Balance Sheets	-200,000,000
Net Amounts of Liabilities Presented	795,000,000	995,000,000
Gross Amounts Not Offset in the Consolidated Balance Sheets
Financial Instruments	-425,000,000	-495,000,000
Collateral Posted	-370,000,000	-500,000,000
Amount recorded in cash and cash equivalents		$100,000,000
[1]	Of the $1.40 billion resale agreements as of December 31, 2013, $100.0 million was recorded in cash and cash equivalents and $1.3 billion was recorded in securities under resale agreements in the consolidated balance sheet.

INVESTMENT_SECURITIES_Details

INVESTMENT SECURITIES (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities
Amortized Cost	$2,619,205		$2,786,490
Gross Unrealized Gains	21,128		12,203
Gross Unrealized Losses	-13,968		-64,896
Fair Value	2,626,365		2,733,797
U.S. Treasury securities
Schedule of Available-for-sale Securities
Amortized Cost	873,101		495,053
Gross Unrealized Gains	1,971		201
Gross Unrealized Losses	-1,637		-3,622
Fair Value	873,435		491,632
U.S. government agency and U.S. government sponsored enterprise debt securities
Schedule of Available-for-sale Securities
Amortized Cost	311,927		406,807
Gross Unrealized Gains	490		242
Gross Unrealized Losses	-1,393		-12,726
Fair Value	311,024		394,323
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities
Schedule of Available-for-sale Securities
Amortized Cost	140,957		182,257
Gross Unrealized Gains	1,056		1,062
Gross Unrealized Losses	-593		-4,449
Fair Value	141,420		178,870
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities
Schedule of Available-for-sale Securities
Amortized Cost	785,412		892,435
Gross Unrealized Gains	9,754		7,729
Gross Unrealized Losses	-4,078		-14,927
Fair Value	791,088		885,237
Municipal securities
Schedule of Available-for-sale Securities
Amortized Cost	245,408		297,390
Gross Unrealized Gains	6,202		1,122
Gross Unrealized Losses	-1,162		-17,533
Fair Value	250,448		280,979
Other residential mortgage-backed securities | Investment grade
Schedule of Available-for-sale Securities
Amortized Cost	52,694	[1]	48,129	[1]
Gross Unrealized Gains	1,359	[1]
Gross Unrealized Losses	-135	[1]	-1,802	[1]
Fair Value	53,918	[1]	46,327	[1]
Other commercial mortgage-backed securities | Investment grade
Schedule of Available-for-sale Securities
Amortized Cost	34,000	[1]	51,000	[1]
Gross Unrealized Gains	53	[1]	617	[1]
Fair Value	34,053	[1]	51,617	[1]
Corporate debt securities | Investment grade
Schedule of Available-for-sale Securities
Amortized Cost	116,236	[1]	312,726	[1]
Gross Unrealized Gains			613	[1]
Gross Unrealized Losses	-1,054	[1]	-3,344	[1]
Fair Value	115,182	[1]	309,995	[1]
Corporate debt securities | Non-investment grade
Schedule of Available-for-sale Securities
Amortized Cost	17,881	[1]	20,668	[1]
Gross Unrealized Gains			62	[1]
Gross Unrealized Losses	-3,200	[1]	-5,629	[1]
Fair Value	14,681	[1]	15,101	[1]
Other securities
Schedule of Available-for-sale Securities
Amortized Cost	41,589		80,025
Gross Unrealized Gains	243		555
Gross Unrealized Losses	-716		-864
Fair Value	$41,116		$79,716
[1]	Investment securities rated BBB- or higher by S&P, or Baa3 or higher by Moody are considered investment grade. Conversely, investment securities rated below BBB- by S&P, or below Baa3 by Moody are considered non-investment grade.

INVESTMENT_SECURITIES_Details_

INVESTMENT SECURITIES (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities
Proceeds from sales	$623,689		$663,569	$1,230,134
Gross realized gains	10,978		13,904	28,211
Gross realized losses	127	[1]	1,815	27,454
Related tax expense	4,557		5,077	318
MetroCorp
Schedule of Available-for-sale Securities
Gross realized losses	$127
[1]	The gross $127 thousand of losses resulted from the investment securities acquired from MetroCorp which were sold immediately after the acquisition closed.

INVESTMENT_SECURITIES_Details_1

INVESTMENT SECURITIES (Details 3) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other than Temporary Impairment, Credit Losses Recognized in Earnings
Other than Temporary Impairment Losses, Investments			$5,165
Other than temporary impairment, pre-tax basis, credit portion recognized in earnings			99
Other than temporary impairment, pre-tax basis, non-credit portion recognized in other comprehensive income			-5,066
Gross realized gains
Gross realized gains	10,978	13,904	28,211
Corporate debt securities | Non-investment grade
Gross realized gains
Gross realized gains	802
Investment securities available for sale
Other than Temporary Impairment, Credit Losses Recognized in Earnings
Beginning balance	115,511		115,412
Additional increases to the amount related to the credit loss for which an OTTI was previously recognized			99
Reduction for securities sold	-3,173
Ending balance	$112,338		$115,511

INVESTMENT_SECURITIES_Details_2

INVESTMENT SECURITIES (Details 4) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Continuous unrealized loss position, fair values of investment securities available-for-sale
Continuous unrealized loss position less than 12 months, fair value	$414,390	$1,803,073
Continuous unrealized loss position less than 12 months, unrealized losses	-2,051	-45,167
Continuous unrealized loss position 12 months or more, fair value	718,223	250,361
Continuous unrealized loss position 12 months or more, unrealized losses	-11,917	-19,729
Continuous unrealized loss position total, fair value	1,132,613	2,053,434
Continuous unrealized loss position total, unrealized losses	-13,968	-64,896
U.S. Treasury securities
Continuous unrealized loss position, fair values of investment securities available-for-sale
Continuous unrealized loss position less than 12 months, fair value	170,260	337,248
Continuous unrealized loss position less than 12 months, unrealized losses	-266	-3,622
Continuous unrealized loss position 12 months or more, fair value	163,800
Continuous unrealized loss position 12 months or more, unrealized losses	-1,371
Continuous unrealized loss position total, fair value	334,060	337,248
Continuous unrealized loss position total, unrealized losses	-1,637	-3,622
Total investment securities available-for-sale portfolio (as a percent)	33.00%	18.00%
U.S. government agency and U.S. government sponsored enterprise debt securities
Continuous unrealized loss position, fair values of investment securities available-for-sale
Continuous unrealized loss position less than 12 months, fair value	69,438	387,097
Continuous unrealized loss position less than 12 months, unrealized losses	-504	-12,726
Continuous unrealized loss position 12 months or more, fair value	124,104
Continuous unrealized loss position 12 months or more, unrealized losses	-889
Continuous unrealized loss position total, fair value	193,542	387,097
Continuous unrealized loss position total, unrealized losses	-1,393	-12,726
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities
Continuous unrealized loss position, fair values of investment securities available-for-sale
Continuous unrealized loss position less than 12 months, fair value	45,405	114,754
Continuous unrealized loss position less than 12 months, unrealized losses	-257	-3,280
Continuous unrealized loss position 12 months or more, fair value	16,169	16,065
Continuous unrealized loss position 12 months or more, unrealized losses	-336	-1,169
Continuous unrealized loss position total, fair value	61,574	130,819
Continuous unrealized loss position total, unrealized losses	-593	-4,449
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities
Continuous unrealized loss position, fair values of investment securities available-for-sale
Continuous unrealized loss position less than 12 months, fair value	81,927	502,285
Continuous unrealized loss position less than 12 months, unrealized losses	-270	-10,570
Continuous unrealized loss position 12 months or more, fair value	241,047	92,540
Continuous unrealized loss position 12 months or more, unrealized losses	-3,808	-4,357
Continuous unrealized loss position total, fair value	322,974	594,825
Continuous unrealized loss position total, unrealized losses	-4,078	-14,927
Total investment securities available-for-sale portfolio (as a percent)	30.00%	32.00%
Municipal securities
Continuous unrealized loss position, fair values of investment securities available-for-sale
Continuous unrealized loss position less than 12 months, fair value	6,391	173,782
Continuous unrealized loss position less than 12 months, unrealized losses	-26	-10,765
Continuous unrealized loss position 12 months or more, fair value	61,107	47,892
Continuous unrealized loss position 12 months or more, unrealized losses	-1,136	-6,768
Continuous unrealized loss position total, fair value	67,498	221,674
Continuous unrealized loss position total, unrealized losses	-1,162	-17,533
Other residential mortgage-backed securities | Investment grade
Continuous unrealized loss position, fair values of investment securities available-for-sale
Continuous unrealized loss position less than 12 months, fair value		46,327
Continuous unrealized loss position less than 12 months, unrealized losses		-1,802
Continuous unrealized loss position 12 months or more, fair value	7,217
Continuous unrealized loss position 12 months or more, unrealized losses	-135
Continuous unrealized loss position total, fair value	7,217	46,327
Continuous unrealized loss position total, unrealized losses	-135	-1,802
Corporate debt securities | Investment grade
Continuous unrealized loss position, fair values of investment securities available-for-sale
Continuous unrealized loss position less than 12 months, fair value	25,084	193,482
Continuous unrealized loss position less than 12 months, unrealized losses	-12	-1,538
Continuous unrealized loss position 12 months or more, fair value	90,098	79,442
Continuous unrealized loss position 12 months or more, unrealized losses	-1,042	-1,806
Continuous unrealized loss position total, fair value	115,182	272,924
Continuous unrealized loss position total, unrealized losses	-1,054	-3,344
Corporate debt securities | Non-investment grade
Continuous unrealized loss position, fair values of investment securities available-for-sale
Continuous unrealized loss position 12 months or more, fair value	14,681	14,422
Continuous unrealized loss position 12 months or more, unrealized losses	-3,200	-5,629
Continuous unrealized loss position total, fair value	14,681	14,422
Continuous unrealized loss position total, unrealized losses	-3,200	-5,629
Total investment securities available-for-sale portfolio (as a percent)	1.00%	1.00%
Other securities
Continuous unrealized loss position, fair values of investment securities available-for-sale
Continuous unrealized loss position less than 12 months, fair value	15,885	48,098
Continuous unrealized loss position less than 12 months, unrealized losses	-716	-864
Continuous unrealized loss position total, fair value	15,885	48,098
Continuous unrealized loss position total, unrealized losses	($716)	($864)

INVESTMENT_SECURITIES_Details_3

INVESTMENT SECURITIES (Details 5) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Scheduled maturities of investment securities available-for sale, amortized cost basis
Due within one year	$343,193,000
Due after one year through five years	1,018,469,000
Due after five years through ten years	328,317,000
Due after ten years	929,226,000
Total investment securities available-for-sale	2,619,205,000
Scheduled maturities of investment securities available-for sale, estimated fair value
Due within one year	339,814,000
Due after one year through five years	1,022,566,000
Due after five years through ten years	329,172,000
Due after ten years	934,813,000
Fair Value	2,626,365,000	2,733,797,000
Par value of securities pledged to secure public deposits	$1,930,000,000	$1,970,000,000

DERIVATIVES_Details

DERIVATIVES (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Designated as Hedging Instrument
Fair Values of Derivative Instruments
Notional amount	$132,667		$135,000
Derivative liabilities	9,922	[1]	16,906	[1]
Designated as Hedging Instrument | Interest rate swaps on certificates of deposits
Fair Values of Derivative Instruments
Notional amount	132,667		135,000
Derivative liabilities	9,922	[1]	16,906	[1]
Derivative instruments not designated as hedging instruments
Fair Values of Derivative Instruments
Notional amount	5,672,472		4,606,619
Derivative assets	55,793		40,549	[1]
Derivative liabilities	54,342	[1]	33,356	[1]
Derivative instruments not designated as hedging instruments | Foreign exchange options
Fair Values of Derivative Instruments
Notional amount	85,614		85,614
Derivative assets	6,136		6,290
Derivative instruments not designated as hedging instruments | Embedded derivatives liabilities
Fair Values of Derivative Instruments
Notional amount	47,838		51,505
Derivative liabilities	3,392	[1]	3,655	[1]
Derivative instruments not designated as hedging instruments | Interest rate swaps and caps
Fair Values of Derivative Instruments
Notional amount	4,858,391		3,834,072
Derivative assets	41,534		28,078	[1]
Derivative liabilities	41,779	[1]	26,352	[1]
Derivative instruments not designated as hedging instruments | Foreign exchange contracts
Fair Values of Derivative Instruments
Notional amount	680,629		635,428
Derivative assets	8,123		6,181
Derivative liabilities	$9,171	[1]	$3,349	[1]
[1]	Derivative assets are included in other assets. Derivative liabilities are included in other liabilities and deposits.

DERIVATIVES_Details_2

DERIVATIVES (Details 2) (Interest rate swaps on certificates of deposits, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Values of Derivative Instruments
Gains (Losses) recognized on interest rate swaps	$6,885	($9,255)	($1,076)
Net amount recognized on fair value hedges (ineffective portion)	101	420	3,610
Net interest expense recognized on interest rate swaps	-6,703	-3,153	-3,793
Certificates of deposits
Fair Values of Derivative Instruments
Gains (Losses) recognized on interest rate swaps	($6,784)	$9,675	$4,686

DERIVATIVES_Details_3

DERIVATIVES (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2007	Dec. 31, 2013
		item
Foreign exchange options
Derivative
Term of contract	5 years
Interest rate swaps and caps
Derivative
Notional amount of derivative assets	2,450,000,000		$1,920,000,000
Notional amount of derivative liabilities	2,400,000,000		1,910,000,000
Short-term foreign exchange contracts
Derivative
Notional amount	680,600,000		607,900,000
Fair value of derivative asset	8,100,000		6,200,000
Fair value of derivative liability	9,200,000		3,300,000
Long-term foreign exchange contracts
Derivative
Notional amount			27,500,000
Fair value of derivative asset			200,000
Fair value of derivative liability			$183,000
Equity swap agreements
Derivative
Number of instruments entered into during the period		2
Term of contract		5 years

DERIVATIVES_Details_4

DERIVATIVES (Details 4) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Derivative Instruments, Gain (Loss)
Cash collateral received	$3,500,000
Cash collateral posted	12,800,000	187,000
Derivative instruments not designated as hedging instruments
Derivative Instruments, Gain (Loss)
Net (losses) gains on derivative instruments	-5,637,000	4,882,000	856,000
Derivative instruments not designated as hedging instruments | Equity swap agreements | Other operating income
Derivative Instruments, Gain (Loss)
Net (losses) gains on derivative instruments			2,000
Derivative instruments not designated as hedging instruments | Foreign exchange options | Foreign exchange income
Derivative Instruments, Gain (Loss)
Net (losses) gains on derivative instruments	103,000	653,000	389,000
Derivative instruments not designated as hedging instruments | Foreign exchange options with embedded derivatives | Other operating expense
Derivative Instruments, Gain (Loss)
Embedded Derivative Gain Loss on Embedded Derivative Net	5,000	23,000	101,000
Derivative instruments not designated as hedging instruments | Interest rate swaps | Other operating income
Derivative Instruments, Gain (Loss)
Net (losses) gains on derivative instruments	-1,865,000	1,582,000	592,000
Derivative instruments not designated as hedging instruments | Foreign exchange contracts | Foreign exchange income
Derivative Instruments, Gain (Loss)
Net (losses) gains on derivative instruments	($3,880,000)	$2,624,000	($228,000)

DERIVATIVES_Details_5

DERIVATIVES (Details 5) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Counterparties assets
Assets, Derivatives
Gross Amounts of Recognized Assets	$12,396		$16,043
Gross Amounts Offset On the Consolidated Balance Sheet	0		0
Net Amounts of Assets Presented	12,396		16,043
Gross Amounts Not Offset
Financial Instruments	-5,725	[1]	-11,363	[1]
Collateral Received	-3,463	[2]	-4,680	[2]
Net Amount	3,208
Counterparties liabilities
Liabilities, Derivatives
Gross Amounts of Recognized Liabilities	56,505		33,849
Gross Amounts Offset On the Consolidated Balance Sheet	0		0
Net Amounts of Liabilities Presented	56,505		33,849
Gross Amounts Not Offset
Financial Instruments	-5,725	[1]	-11,363	[1]
Collateral Posted	-49,951	[3]	-22,486	[3]
Net Amount	$829
[1]	Represents the netting of derivative receivable and payable balance for the same counterparty under enforceable master netting arrangements if the Company has elected to net.
[2]	Represents cash and securities received against derivative assets with the same counterparty that are subject to enforceable master netting arrangements. Includes approximately $3.5 million of cash collateral received as of December 31, 2014.
[3]	Represents cash and securities pledged against derivative liabilities with the same counterparty th tare subject to enforceable master netting arrangements. Includes approximately $12.8 million and $187 thousand of cash collateral posted as of December 31, 2014 and December 31, 2013, respectively.

COVERED_ASSETS_AND_FDIC_INDEMN2

COVERED ASSETS AND FDIC INDEMNIFICATION ASSET (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule Of Covered Assets - disclosures
Percentage of eligible losses for which the FDIC is obligated to reimburse the Company	80.00%	80.00%	80.00%
Covered loans (net of allowance for loan losses of $3,505 in 2014 and $7,745 in 2013)	$1,474,189,000	$2,187,898,000
Covered Loans
Schedule Of Covered Assets - disclosures
Covered loans (net of allowance for loan losses of $3,505 in 2014 and $7,745 in 2013)	1,474,189,000	2,187,898,000
Number of days following the 10th anniversary of the acquisition date upon which the Company will be required to pay a calculated amount to the FDIC	45 days
Percentage of excess resulting from the calculation of liability to the FDIC	50.00%
Percentage of the Intrinsic Loss Estimate used in the calculation of the liability to the FDIC	20.00%
Percentage of the asset discount used in the calculation of the liability to the FDIC	25.00%
Percentage of the Cumulative Shared-Loss Payments used in the calculation of the liability to the FDIC	25.00%
Estimated liability that will be due to the FDIC based on specific thresholds of losses not being reached	110,300,000	74,700,000
Covered Loans | C&I
Schedule Of Covered Assets - disclosures
Term of loan shared-loss agreement	5 years
Term of loss recovery provisions for loans	8 years
UCB Commercial loans and other assets, net of discount	1,100,000,000
Covered Loans | Single-family
Schedule Of Covered Assets - disclosures
Term of loan shared-loss agreement	10 years
Term of loss recovery provisions for loans	10 years
Effective period to term of loan shared-loss agreement and loss recovery provisions for loans	10 years
Covered Loans | United Commercial Bank (UCB)
Schedule Of Covered Assets - disclosures
Percentage of eligible losses for which the FDIC is obligated to reimburse the Company	80.00%
Percentage of eligible losses in excess of a specified amount for which the FDIC is obligated to reimburse the Company	95.00%
Amount of eligible losses over which the FDIC is obligated to reimburse a higher percentage	$2,050,000,000
Percentage obligation to reimburse the FDIC for eligible recoveries related to covered assets	80.00%
Percentage obligation to reimburse the FDIC for eligible recoveries related to losses in excess of a specified amount on covered assets	95.00%
Covered Loans | United Commercial Bank (UCB) | C&I
Schedule Of Covered Assets - disclosures
The period of time for commercial loan shared-loss agreements are in effect	3 years
Covered Loans | United Commercial Bank (UCB) | Single-family
Schedule Of Covered Assets - disclosures
The period of time for commercial loan shared-loss agreements are in effect	10 years
Covered Loans | Washington First International Bank (WFIB)
Schedule Of Covered Assets - disclosures
Percentage of eligible losses for which the FDIC is obligated to reimburse the Company	80.00%
Percentage of eligible losses in excess of a specified amount for which the FDIC is obligated to reimburse the Company	95.00%
Percentage obligation to reimburse the FDIC for eligible recoveries related to covered assets	80.00%
Percentage obligation to reimburse the FDIC for eligible recoveries related to losses in excess of a specified amount on covered assets	95.00%
The period of time for commercial loan shared-loss agreements are in effect	3 years
Covered Loans | Washington First International Bank (WFIB) | Minimum
Schedule Of Covered Assets - disclosures
Percentage of loans receivable acquired covered by shared-loss agreements	99.00%
Covered Loans | Washington First International Bank (WFIB) | Single-family
Schedule Of Covered Assets - disclosures
The period of time for commercial loan shared-loss agreements are in effect	10 years

COVERED_ASSETS_AND_FDIC_INDEMN3

COVERED ASSETS AND FDIC INDEMNIFICATION ASSET (Details 2) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Carrying Amounts And Composition Of Covered Loans
Allowance for loan losses on covered loans	($3,505)		($7,745)
Total covered loans, net	1,474,189		2,187,898
Covered Loans
Carrying Amounts And Composition Of Covered Loans
Total covered loans	1,604,940	[1]	2,461,560	[2]
Covered discount	-127,246		-265,917
Net valuation of loans	1,477,694		2,195,643
Allowance for loan losses on covered loans	-3,505		-7,745
Total covered loans, net	1,474,189		2,187,898
Collectively evaluated for impairment	253,312	[1]	320,185	[2]
Acquired with deteriorated credit quality	1,224,382		1,875,458
Covered Loans | Covered Advances
Carrying Amounts And Composition Of Covered Loans
Total covered loans	253,300		320,200
Collectively evaluated for impairment	253,300		320,200
Covered Loans | CRE
Carrying Amounts And Composition Of Covered Loans
Total covered loans	751,719		1,267,363
Covered Loans | CRE | Covered Advances
Carrying Amounts And Composition Of Covered Loans
Total covered loans	59,400		46,700
Collectively evaluated for impairment	59,400		46,700
Covered Loans | CRE | CRE
Carrying Amounts And Composition Of Covered Loans
Total covered loans	705,665		1,103,530
Covered Loans | CRE | Construction and land
Carrying Amounts And Composition Of Covered Loans
Total covered loans	46,054		163,833
Covered Loans | C&I
Carrying Amounts And Composition Of Covered Loans
Total covered loans	252,986		426,621
Covered Loans | C&I | Covered Advances
Carrying Amounts And Composition Of Covered Loans
Total covered loans	154,800		230,600
Collectively evaluated for impairment	154,800		230,600
Covered Loans | Residential
Carrying Amounts And Composition Of Covered Loans
Total covered loans	537,249		693,603
Covered Loans | Residential | Covered Advances
Carrying Amounts And Composition Of Covered Loans
Total covered loans	11,800		12,000
Collectively evaluated for impairment	11,800		12,000
Covered Loans | Residential | Single-family
Carrying Amounts And Composition Of Covered Loans
Total covered loans	240,650		290,095
Covered Loans | Residential | Multifamily
Carrying Amounts And Composition Of Covered Loans
Total covered loans	296,599		403,508
Covered Loans | Consumer | Covered Advances
Carrying Amounts And Composition Of Covered Loans
Total covered loans	27,300		30,900
Collectively evaluated for impairment	27,300		30,900
Covered Loans | Consumer | Other Consumer
Carrying Amounts And Composition Of Covered Loans
Total covered loans	$62,986		$73,973
[1]	Includes $253.3 million of covered advances comprised of $154.8 million, $59.4 million, $27.3 million and $11.8 million of C&I, CRE, consumer and residential loans, respectively.
[2]	Includes $320.2 million of covered advances comprised of $230.6 million, $46.7 million, $30.9 million and $12.0 million of C&I, CRE, consumer and residential loans, respectively.

COVERED_ASSETS_AND_FDIC_INDEMN4

COVERED ASSETS AND FDIC INDEMNIFICATION ASSET (Details 4) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
	item
Allowance for loan losses disclosures
The number of grades used for the loan risk rating system	8
Financing Receivable Allowance for Credit Losses Roll Forward
Provision for (reversal of) loan losses	$49,158		$22,364		$65,184
Covered Loans
Allowance for loan losses disclosures
Principal Balance	1,604,940	[1]	2,461,560	[2]
Covered Loans | Total
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	7,745		5,153		6,647
Provision for (reversal of) loan losses	5,033		4,028		5,016
Charge-offs	-10,836		-1,436		-6,510
Recoveries	1,563
Ending balance	3,505		7,745		5,153
Ending balance allocated to:
Collectively evaluated for impairment	3,081	[3]	5,476	[4]	5,153	[5]
Acquired with deteriorated credit quality	424		2,269
Allowance on covered loans	3,505		7,745		5,153
Covered Loans | Covered Advances
Allowance for loan losses disclosures
Principal Balance	253,300		320,200
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	5,476	[4]	5,153		6,647
Provision for (reversal of) loan losses	6,878		1,759		5,016
Charge-offs	-10,836		-1,436		-6,510
Recoveries	1,563
Ending balance	3,081	[3]	5,476	[4]	5,153
Ending balance allocated to:
Collectively evaluated for impairment	3,081	[3]	5,476	[4]	5,153
Allowance on covered loans	3,081	[3]	5,476	[4]	5,153
Covered Loans | PCI Covered Loans
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	2,269
Provision for (reversal of) loan losses	-1,845		2,269
Ending balance	424		2,269
Ending balance allocated to:
Acquired with deteriorated credit quality	424		2,269
Allowance on covered loans	424		2,269
CRE | Covered Loans
Allowance for loan losses disclosures
Principal Balance	751,719		1,267,363
CRE | Covered Loans | Covered Advances
Allowance for loan losses disclosures
Principal Balance	59,400		46,700
Financing Receivable Allowance for Credit Losses Roll Forward
Ending balance	676		1,800		2,500
Ending balance allocated to:
Collectively evaluated for impairment	676		1,800
Allowance on covered loans	676		1,800		2,500
C&I | Covered Loans
Allowance for loan losses disclosures
Principal Balance	252,986		426,621
C&I | Covered Loans | Covered Advances
Allowance for loan losses disclosures
Principal Balance	154,800		230,600
Financing Receivable Allowance for Credit Losses Roll Forward
Ending balance	2,000		3,200		2,400
Ending balance allocated to:
Collectively evaluated for impairment	2,000		3,200
Allowance on covered loans	2,000		3,200		2,400
Residential | Covered Loans
Allowance for loan losses disclosures
Principal Balance	537,249		693,603
Residential | Covered Loans | Covered Advances
Allowance for loan losses disclosures
Principal Balance	11,800		12,000
Financing Receivable Allowance for Credit Losses Roll Forward
Ending balance	166		176		87
Ending balance allocated to:
Collectively evaluated for impairment	166		176
Allowance on covered loans	166		176		87
Consumer | Covered Loans | Covered Advances
Allowance for loan losses disclosures
Principal Balance	27,300		30,900
Financing Receivable Allowance for Credit Losses Roll Forward
Ending balance	223		341		194
Ending balance allocated to:
Collectively evaluated for impairment	223		341
Allowance on covered loans	$223		$341		$194
[1]	Includes $253.3 million of covered advances comprised of $154.8 million, $59.4 million, $27.3 million and $11.8 million of C&I, CRE, consumer and residential loans, respectively.
[2]	Includes $320.2 million of covered advances comprised of $230.6 million, $46.7 million, $30.9 million and $12.0 million of C&I, CRE, consumer and residential loans, respectively.
[3]	Allowance for loan losses of $2.0 million, $676 thousand, $223 thousand and $166 thousand are allocated to C&I, CRE, consumer and residential loans, respectively.
[4]	Allowance for loan losses of $3.2 million, $1.8 million, $341 thousand and $176 thousand are allocated to C&I, CRE, consumer and residential loans, respectively.
[5]	Allowance for loan losses of $2.4 million, $2.5 million and $194 thousand and $87 thousand are allocated to C&I, CRE, consumer and residential loans, respectively

COVERED_ASSETS_AND_FDIC_INDEMN5

COVERED ASSETS AND FDIC INDEMNIFICATION ASSET (Details 5) (Covered Loans, USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Carrying Amounts And Composition Of Covered Loans
Total principal balance	$1,604,940	[1]	$2,461,560	[2]
PCI Covered Loans
Carrying Amounts And Composition Of Covered Loans
Principal Balance	61,600		129,700
Pass/Watch
Carrying Amounts And Composition Of Covered Loans
Total principal balance	1,357,240		2,003,632
Special Mention
Carrying Amounts And Composition Of Covered Loans
Total principal balance	27,428		43,604
Substandard
Carrying Amounts And Composition Of Covered Loans
Total principal balance	220,272		406,855
Doubtful
Carrying Amounts And Composition Of Covered Loans
Total principal balance	0		7,469
CRE
Carrying Amounts And Composition Of Covered Loans
Total principal balance	751,719		1,267,363
CRE | Pass/Watch
Carrying Amounts And Composition Of Covered Loans
Total principal balance	597,223		899,223
CRE | Special Mention
Carrying Amounts And Composition Of Covered Loans
Total principal balance	21,090		37,323
CRE | Substandard
Carrying Amounts And Composition Of Covered Loans
Total principal balance	133,406		323,451
CRE | Doubtful
Carrying Amounts And Composition Of Covered Loans
Total principal balance	0		7,366
CRE | CRE
Carrying Amounts And Composition Of Covered Loans
Total principal balance	705,665		1,103,530
CRE | CRE | Pass/Watch
Carrying Amounts And Composition Of Covered Loans
Total principal balance	579,133		857,376
CRE | CRE | Special Mention
Carrying Amounts And Composition Of Covered Loans
Total principal balance	12,575		27,851
CRE | CRE | Substandard
Carrying Amounts And Composition Of Covered Loans
Total principal balance	113,957		211,835
CRE | CRE | Doubtful
Carrying Amounts And Composition Of Covered Loans
Total principal balance	0		6,468
CRE | Construction and land
Carrying Amounts And Composition Of Covered Loans
Total principal balance	46,054		163,833
CRE | Construction and land | Pass/Watch
Carrying Amounts And Composition Of Covered Loans
Total principal balance	18,090		41,847
CRE | Construction and land | Special Mention
Carrying Amounts And Composition Of Covered Loans
Total principal balance	8,515		9,472
CRE | Construction and land | Substandard
Carrying Amounts And Composition Of Covered Loans
Total principal balance	19,449		111,616
CRE | Construction and land | Doubtful
Carrying Amounts And Composition Of Covered Loans
Total principal balance	0		898
C&I
Carrying Amounts And Composition Of Covered Loans
Total principal balance	252,986		426,621
C&I | Pass/Watch
Carrying Amounts And Composition Of Covered Loans
Total principal balance	217,975		378,086
C&I | Special Mention
Carrying Amounts And Composition Of Covered Loans
Total principal balance	5,723		4,635
C&I | Doubtful
Carrying Amounts And Composition Of Covered Loans
Total principal balance	0		103
C&I | Commercial business | Substandard
Carrying Amounts And Composition Of Covered Loans
Total principal balance	29,288		43,797
Residential
Carrying Amounts And Composition Of Covered Loans
Total principal balance	537,249		693,603
Residential | Pass/Watch
Carrying Amounts And Composition Of Covered Loans
Total principal balance	480,032		654,270
Residential | Special Mention
Carrying Amounts And Composition Of Covered Loans
Total principal balance	474		1,518
Residential | Substandard
Carrying Amounts And Composition Of Covered Loans
Total principal balance	56,743		37,815
Residential | Single-family
Carrying Amounts And Composition Of Covered Loans
Total principal balance	240,650		290,095
Residential | Single-family | Pass/Watch
Carrying Amounts And Composition Of Covered Loans
Total principal balance	232,139		281,246
Residential | Single-family | Special Mention
Carrying Amounts And Composition Of Covered Loans
Total principal balance	474		733
Residential | Single-family | Substandard
Carrying Amounts And Composition Of Covered Loans
Total principal balance	8,037		8,116
Residential | Multifamily
Carrying Amounts And Composition Of Covered Loans
Total principal balance	296,599		403,508
Residential | Multifamily | Pass/Watch
Carrying Amounts And Composition Of Covered Loans
Total principal balance	247,893		373,024
Residential | Multifamily | Special Mention
Carrying Amounts And Composition Of Covered Loans
Total principal balance	0		785
Residential | Multifamily | Substandard
Carrying Amounts And Composition Of Covered Loans
Total principal balance	48,706		29,699
Consumer | Other Consumer
Carrying Amounts And Composition Of Covered Loans
Total principal balance	62,986		73,973
Consumer | Other Consumer | Pass/Watch
Carrying Amounts And Composition Of Covered Loans
Total principal balance	62,010		72,053
Consumer | Other Consumer | Special Mention
Carrying Amounts And Composition Of Covered Loans
Total principal balance	141		128
Consumer | Other Consumer | Substandard
Carrying Amounts And Composition Of Covered Loans
Total principal balance	$835		$1,792
[1]	Includes $253.3 million of covered advances comprised of $154.8 million, $59.4 million, $27.3 million and $11.8 million of C&I, CRE, consumer and residential loans, respectively.
[2]	Includes $320.2 million of covered advances comprised of $230.6 million, $46.7 million, $30.9 million and $12.0 million of C&I, CRE, consumer and residential loans, respectively.

COVERED_ASSETS_AND_FDIC_INDEMN6

COVERED ASSETS AND FDIC INDEMNIFICATION ASSET (Details 6) (USD $)	12 Months Ended					0 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012	Nov. 06, 2009
Covered Nonperforming Assets
Other real estate owned covered, net	$4,499,000		$21,373,000
Number of past due days for the loans receivable to be placed on nonaccrual status	90 days
Covered assets - other disclosures
Interest income related to loans removed	87,500,000		168,100,000
Covered Loans
Covered Nonperforming Assets
Covered nonaccrual loans	62,665,000	[1],[2],[3]	126,895,000	[1],[2],[3]
Other real estate owned covered, net	4,499,000		21,373,000
Total covered nonperforming assets	67,164,000		148,268,000
Percentage of any reimbursable expense recorded as interest income under ASC 310-30	80.00%
Covered loans past due 90 days or more but not on nonaccrual	0		0
Number of past due days for the loans receivable to be placed on nonaccrual status	90 days		90 days
Covered TDR activity
Beginning balance	116,007,000		157,736,000
Additions	1,264,000		35,865,000
Transfers to covered OREO	-1,230,000
Charge-offs	-1,504,000		-10,167,000
Paydowns/Reductions	-71,810,000		-67,427,000
Ending Balance	42,727,000		116,007,000		157,736,000
Changes in the accretable yield for the covered loans
Beginning balance	461,545,000		556,986,000		785,165,000
Accretion	-214,209,000		-347,010,000		-382,132,000
Changes in expected cash flows	59,188,000		251,569,000		153,953,000
Ending Balance	306,524,000		461,545,000		556,986,000
Covered assets - other disclosures
Amount reclassified from nonaccretable yield to accretable yield due to changes in loss rate assumptions	52,500,000		190,300,000
Amount of loans removed from the covered loans accounted for under ASC 310-30, excluding scheduled principal payments	647,000,000		739,300,000		924,700,000
Interest income related to loans removed	87,500,000		168,100,000		124,700,000
Covered Loans | Covered Advances
Covered Nonperforming Assets
Covered nonaccrual loans	10,100,000		17,700,000
Covered Loans | PCI Covered Loans
Covered Nonperforming Assets
Covered nonaccrual loans	52,600,000		109,200,000
Covered Loans | Covered OREO Properties
Covered Nonperforming Assets
Covered OREO balances	4,500,000
Number of covered OREO properties added during the period	17
Aggregate carrying value of covered OREO properties added during the period	28,000,000		21,400,000
Net valuation adjustments included in aggregate carrying value on covered OREO properties	1,300,000		2,400,000
Number of covered OREO properties sold during the period	29
Total proceeds value of covered OREO properties sold during the period	52,100,000
Total net gains (losses) on covered OREO properties sold during the period	$8,500,000
Covered Loans | United Commercial Bank (UCB)
Credit Risk and Concentrations
Percentage of the entity's total covered loans acquired from a specific counterparty	93.00%
Number of general geographic regions	3
Covered Loans | United Commercial Bank (UCB) | Covered loans acquired from specific acquiree | Geographic Concentration | California | PCI Covered Loans
Credit Risk and Concentrations
Percent of total						64.00%
Covered Loans | United Commercial Bank (UCB) | Covered loans acquired from specific acquiree | Geographic Concentration | New York | PCI Covered Loans
Credit Risk and Concentrations
Percent of total						11.00%
Covered Loans | United Commercial Bank (UCB) | Covered loans acquired from specific acquiree | Geographic Concentration | Hong Kong | PCI Covered Loans
Credit Risk and Concentrations
Percent of total						10.00%
[1]	Covered nonaccrual loans include loans that meet the criteria for nonaccrual but have a yield accreted through interest income under ASC 310-30.All losses on covered loans are 80% reimbursed by the FDIC.
[2]	Net of discount.
[3]	Includes $10.1 million and $17.7 million of covered advances as of December 31, 2014 and December 31, 2013, respectively; and $52.6 million and $109.2 million of PCI loans as of December 31, 2014 and December 31, 2013, respectively.

COVERED_ASSETS_AND_FDIC_INDEMN7

COVERED ASSETS AND FDIC INDEMNIFICATION ASSET (Details 7) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
FDIC indemnification asset/(Payable to FDIC, net)
Ending Balance	$96,106
FDIC receivable activity
Payments received from the FDIC	-1,343		55,826		76,094
Covered Loans
FDIC indemnification asset/(Payable to FDIC, net)
Beginning balance	74,708		316,313
(Amortization) Accretion	-101,638		-99,055
Reductions	-33,595	[1]	-95,536	[1]
Estimate of FDIC repayment	-35,581	[2]	-47,014	[2]
Ending Balance	-96,106		74,708
FDIC Receivable
Percentage of reimbursable expenses that are loan-related and OREO expenses that are recorded as non-interest expense	100.00%
Percentage of any reimbursable expense recorded as noninterest income	80.00%
Percentage of actual expense paid by the Company	20.00%
Percentage of Recoveries received	80.00%
FDIC receivable activity
Beginning balance	30,261		73,091
Net (reduction) addition due to recovery or eligible expense/loss	-30,601		12,996
Payments received from the FDIC	1,343		-55,826
Ending Balance	$1,003		$30,261
[1]	Reductions relate to charge-offs, partial prepayments, loan payoffs and loan sales which result in a corresponding reduction of the indemnification asset.
[2]	This represents the change in the calculated estimate the Company will be required to pay the FDIC at the end of the FDIC shared-loss agreements, due to lower thresholds of losses.

NONCOVERED_LOANS_AND_ALLOWANCE2

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Non-Covered loans receivable disclosures
Allowance for loan losses on non-covered loans	($258,174)		($241,930)
Non-covered loans receivable, excluding covered loans, net	19,994,081		15,412,715
Non-covered loans
Non-Covered loans receivable disclosures
Non-Covered Loans	20,249,451	[1]	15,678,317	[1]
Unearned fees, premiums and discounts, net	2,804		-23,672
Allowance for loan losses on non-covered loans	-258,174		-241,930
Non-covered loans receivable, excluding covered loans, net	19,994,081		15,412,715
CRE | Non-covered loans
Non-Covered loans receivable disclosures
Non-Covered Loans	6,134,046		4,585,077
CRE | Income producing | Non-covered loans
Non-Covered loans receivable disclosures
Non-Covered Loans	5,611,485		4,301,030
CRE | Construction | Non-covered loans
Non-Covered loans receivable disclosures
Non-Covered Loans	313,811		140,186
CRE | Land | Non-covered loans
Non-Covered loans receivable disclosures
Non-Covered Loans	208,750		143,861
C&I | Non-covered loans
Non-Covered loans receivable disclosures
Non-Covered Loans	7,838,094		5,360,193
C&I | Commercial business | Non-covered loans
Non-Covered loans receivable disclosures
Non-Covered Loans	7,031,350		4,637,056
C&I | Trade finance | Non-covered loans
Non-Covered loans receivable disclosures
Non-Covered Loans	806,744		723,137
Residential | Non-covered loans
Non-Covered loans receivable disclosures
Non-Covered Loans	4,820,668		4,185,309
Residential | Single-family | Non-covered loans
Non-Covered loans receivable disclosures
Non-Covered Loans	3,642,978		3,192,875
Residential | Multifamily | Non-covered loans
Non-Covered loans receivable disclosures
Non-Covered Loans	1,177,690		992,434
Consumer | Non-covered loans
Non-Covered loans receivable disclosures
Non-Covered Loans	1,456,643		1,547,738
Consumer | Student loans | Non-covered loans
Non-Covered loans receivable disclosures
Non-Covered Loans			679,220
Consumer | Other Consumer | Non-covered loans
Non-Covered loans receivable disclosures
Non-Covered Loans	$1,456,643		$868,518
[1]	Loans net of ASC 310-30 discount.

NONCOVERED_LOANS_AND_ALLOWANCE3

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 2) (USD $)	12 Months Ended
In Billions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
	item
Non-Covered loans receivable disclosures
Covered and non-covered loans receivable pledged to secure borrowings from the FHLB and the Federal Reserve Bank	14.66	$10.57
Residential | Single-family | Minimum | Non-covered loans
Non-Covered loans receivable disclosures
Number of units of residential property securing fixed and adjustable rate first mortgage loans	1
Adjustable rate mortgage, term of initial fixed interest rates	1 year
Residential | Single-family | Maximum | Non-covered loans
Non-Covered loans receivable disclosures
Number of units of residential property securing fixed and adjustable rate first mortgage loans	4
Adjustable rate mortgage, term of initial fixed interest rates	3 years
Residential | Multifamily | Minimum | Non-covered loans
Non-Covered loans receivable disclosures
Adjustable rate mortgage, term of initial fixed interest rates	6 months
Residential | Multifamily | Maximum | Non-covered loans
Non-Covered loans receivable disclosures
Adjustable rate mortgage, term of initial fixed interest rates	3 years

NONCOVERED_LOANS_AND_ALLOWANCE4

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 3) (USD $)	12 Months Ended					0 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012	Jan. 17, 2014
Loans Held for Sale
Total loans held for sale	$45,950,000		$204,970,000
Write-down of loans transferred from loans held for investment to loans held for sale recorded to allowance for loan losses	5,200,000		0
Loans receivable reclassified to loans held for sale	837,389,000		97,065,000		144,131,000
Non-covered loans
Credit Risk and Concentrations
Percentage of non-covered commercial real estate loans and non-covered residential loans secured by real properties located in California	80.00%
Non-Covered Loans	20,249,451,000	[1]	15,678,317,000	[1]
Purchased Loans
Loans purchased during the period	113,200,000		759,300,000
Percentage of purchased loans classified as student loans			63.00%
Loans Held for Sale
Total loans held for sale	46,000,000		205,000,000
Proceeds from the sales of Loans held for sale, including loans reclassified to loans held for sale	1,140,000,000		376,400,000		428,700,000
Net gain from sale of loans held for sale during the period	39,100,000		7,800,000		17,000,000
Loans receivable reclassified to loans held for sale	837,400,000		97,100,000
MetroCorp
Acquired Loans
Loans acquired during the period						1,190,000,000
MetroCorp | Non-covered loans
Acquired Loans
Loans acquired during the period						1,190,000,000
Acquired loans accounted (as a percent)						6.00%
PCI loans	50,600,000
Residential | Non-covered loans
Credit Risk and Concentrations
Non-Covered Loans	4,820,668,000		4,185,309,000
CRE | Non-covered loans
Credit Risk and Concentrations
Non-Covered Loans	$6,134,046,000		$4,585,077,000
[1]	Loans net of ASC 310-30 discount.

NONCOVERED_LOANS_AND_ALLOWANCE5

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 4) (Non-covered loans, USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified	item
Credit Quality Indicators
Number of grades in the risk rating system utilized by the company to rate credit risk of loans receivable	8
Total non-covered loans	$20,249,451	[1]	$15,678,317	[1]
Pass/Watch
Credit Quality Indicators
Total non-covered loans	19,453,512		14,991,479
Special Mention
Credit Quality Indicators
Total non-covered loans	208,175		197,284
Substandard
Credit Quality Indicators
Total non-covered loans	587,176		489,554
Doubtful
Credit Quality Indicators
Total non-covered loans	533
Loss
Credit Quality Indicators
Total non-covered loans	55
CRE
Credit Quality Indicators
Total non-covered loans	6,134,046		4,585,077
CRE | Construction
Credit Quality Indicators
Total non-covered loans	313,811		140,186
CRE | Construction | Pass/Watch
Credit Quality Indicators
Total non-covered loans	306,923		127,138
CRE | Construction | Special Mention
Credit Quality Indicators
Total non-covered loans			6,160
CRE | Construction | Substandard
Credit Quality Indicators
Total non-covered loans	6,888		6,888
CRE | Land
Credit Quality Indicators
Total non-covered loans	208,750		143,861
CRE | Land | Pass/Watch
Credit Quality Indicators
Total non-covered loans	179,319		116,000
CRE | Land | Special Mention
Credit Quality Indicators
Total non-covered loans	5,701		9,304
CRE | Land | Substandard
Credit Quality Indicators
Total non-covered loans	23,730		18,557
CRE | Income producing
Credit Quality Indicators
Total non-covered loans	5,611,485		4,301,030
CRE | Income producing | Pass/Watch
Credit Quality Indicators
Total non-covered loans	5,244,022		4,032,269
CRE | Income producing | Special Mention
Credit Quality Indicators
Total non-covered loans	54,431		56,752
CRE | Income producing | Substandard
Credit Quality Indicators
Total non-covered loans	313,032		212,009
C&I
Credit Quality Indicators
Total non-covered loans	7,838,094		5,360,193
C&I | Commercial business
Credit Quality Indicators
Total non-covered loans	7,031,350		4,637,056
C&I | Commercial business | Pass/Watch
Credit Quality Indicators
Total non-covered loans	6,783,051		4,400,847
C&I | Commercial business | Special Mention
Credit Quality Indicators
Total non-covered loans	128,578		92,315
C&I | Commercial business | Substandard
Credit Quality Indicators
Total non-covered loans	119,133		143,894
C&I | Commercial business | Doubtful
Credit Quality Indicators
Total non-covered loans	533
C&I | Commercial business | Loss
Credit Quality Indicators
Total non-covered loans	55
C&I | Trade finance
Credit Quality Indicators
Total non-covered loans	806,744		723,137
C&I | Trade finance | Pass/Watch
Credit Quality Indicators
Total non-covered loans	766,575		681,345
C&I | Trade finance | Special Mention
Credit Quality Indicators
Total non-covered loans	10,193		22,099
C&I | Trade finance | Substandard
Credit Quality Indicators
Total non-covered loans	29,976		19,693
Residential
Credit Quality Indicators
Total non-covered loans	4,820,668		4,185,309
Residential | Single-family
Credit Quality Indicators
Total non-covered loans	3,642,978		3,192,875
Residential | Single-family | Pass/Watch
Credit Quality Indicators
Total non-covered loans	3,624,097		3,167,337
Residential | Single-family | Special Mention
Credit Quality Indicators
Total non-covered loans	3,143		8,331
Residential | Single-family | Substandard
Credit Quality Indicators
Total non-covered loans	15,738		17,207
Residential | Multifamily
Credit Quality Indicators
Total non-covered loans	1,177,690		992,434
Residential | Multifamily | Pass/Watch
Credit Quality Indicators
Total non-covered loans	1,096,572		923,697
Residential | Multifamily | Special Mention
Credit Quality Indicators
Total non-covered loans	5,124		1,634
Residential | Multifamily | Substandard
Credit Quality Indicators
Total non-covered loans	75,994		67,103
Consumer
Credit Quality Indicators
Total non-covered loans	1,456,643		1,547,738
Consumer | Student loans
Credit Quality Indicators
Total non-covered loans			679,220
Consumer | Student loans | Pass/Watch
Credit Quality Indicators
Total non-covered loans			677,094
Consumer | Student loans | Special Mention
Credit Quality Indicators
Total non-covered loans			445
Consumer | Student loans | Substandard
Credit Quality Indicators
Total non-covered loans			1,681
Consumer | Other Consumer
Credit Quality Indicators
Total non-covered loans	1,456,643		868,518
Consumer | Other Consumer | Pass/Watch
Credit Quality Indicators
Total non-covered loans	1,452,953		865,752
Consumer | Other Consumer | Special Mention
Credit Quality Indicators
Total non-covered loans	1,005		244
Consumer | Other Consumer | Substandard
Credit Quality Indicators
Total non-covered loans	$2,685		$2,522
[1]	Loans net of ASC 310-30 discount.

NONCOVERED_LOANS_AND_ALLOWANCE6

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 5) (Non-covered loans, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Aging analysis of past Due non-covered loans and loans held for sale
Number of days a loan is past due and is placed on nonaccrual status	90 days
Accruing loans 30 - 59 days past due	$30,765	[1]	$30,282
Accruing loans 60 - 89 days past due	8,615	[1]	9,956
Total accruing past due loans	39,380	[1]	40,238
Nonaccrual loans less than 90 days past due	50,886	[1]	40,462
Nonaccrual loans 90 or more days past due	50,157	[1]	71,189
Total nonaccrual past due loans	101,043	[1]	111,651
Current Accruing loans	20,154,978	[1]	15,731,398
Total non-covered loans and loans held for sale, gross	20,295,401	[1]	15,883,287
Unearned fees, premiums and discounts, net	2,804		-23,672
Recorded investment in non-covered loans and loans held for sale	20,298,205		15,859,615
Loans Held for Sale
Aging analysis of past Due non-covered loans and loans held for sale
Accruing loans 30 - 59 days past due	642
Accruing loans 60 - 89 days past due	175
Total accruing past due loans	817
Nonaccrual loans less than 90 days past due	0
Nonaccrual loans 90 or more days past due	3,157
Total nonaccrual past due loans	3,157
Current Accruing loans	41,976		204,970
Total non-covered loans and loans held for sale, gross	45,950		204,970
CRE | Construction
Aging analysis of past Due non-covered loans and loans held for sale
Nonaccrual loans 90 or more days past due	6,888		6,888
Total nonaccrual past due loans	6,888		6,888
Current Accruing loans	306,923		133,298
Total non-covered loans and loans held for sale, gross	313,811		140,186
CRE | Land
Aging analysis of past Due non-covered loans and loans held for sale
Nonaccrual loans less than 90 days past due	254		265
Nonaccrual loans 90 or more days past due	2,502		3,223
Total nonaccrual past due loans	2,756		3,488
Current Accruing loans	205,994		140,373
Total non-covered loans and loans held for sale, gross	208,750		143,861
CRE | Income producing
Aging analysis of past Due non-covered loans and loans held for sale
Accruing loans 30 - 59 days past due	14,171		12,746
Accruing loans 60 - 89 days past due	3,593		1,798
Total accruing past due loans	17,764		14,544
Nonaccrual loans less than 90 days past due	29,576		13,924
Nonaccrual loans 90 or more days past due	9,109		22,549
Total nonaccrual past due loans	38,685		36,473
Current Accruing loans	5,555,036		4,250,013
Total non-covered loans and loans held for sale, gross	5,611,485		4,301,030
C&I | Commercial business
Aging analysis of past Due non-covered loans and loans held for sale
Accruing loans 30 - 59 days past due	3,073		3,428
Accruing loans 60 - 89 days past due	2,884		6,259
Total accruing past due loans	5,957		9,687
Nonaccrual loans less than 90 days past due	5,514		6,437
Nonaccrual loans 90 or more days past due	14,689		15,486
Total nonaccrual past due loans	20,203		21,923
Current Accruing loans	7,005,190		4,605,446
Total non-covered loans and loans held for sale, gross	7,031,350		4,637,056
C&I | Trade finance
Aging analysis of past Due non-covered loans and loans held for sale
Nonaccrual loans less than 90 days past due	73
Nonaccrual loans 90 or more days past due			909
Total nonaccrual past due loans	73		909
Current Accruing loans	806,671		722,228
Total non-covered loans and loans held for sale, gross	806,744		723,137
Residential | Single-family
Aging analysis of past Due non-covered loans and loans held for sale
Accruing loans 30 - 59 days past due	6,375		4,694
Accruing loans 60 - 89 days past due	1,294		922
Total accruing past due loans	7,669		5,616
Nonaccrual loans less than 90 days past due	2,894
Nonaccrual loans 90 or more days past due	4,936		11,218
Total nonaccrual past due loans	7,830		11,218
Current Accruing loans	3,627,479		3,176,041
Total non-covered loans and loans held for sale, gross	3,642,978		3,192,875
Residential | Multifamily
Aging analysis of past Due non-covered loans and loans held for sale
Accruing loans 30 - 59 days past due	4,350		8,580
Accruing loans 60 - 89 days past due	507		531
Total accruing past due loans	4,857		9,111
Nonaccrual loans less than 90 days past due	12,460		19,661
Nonaccrual loans 90 or more days past due	8,336		7,972
Total nonaccrual past due loans	20,796		27,633
Current Accruing loans	1,152,037		955,690
Total non-covered loans and loans held for sale, gross	1,177,690		992,434
Consumer | Student loans
Aging analysis of past Due non-covered loans and loans held for sale
Accruing loans 30 - 59 days past due			541
Accruing loans 60 - 89 days past due			445
Total accruing past due loans			986
Nonaccrual loans 90 or more days past due			1,681
Total nonaccrual past due loans			1,681
Current Accruing loans			676,553
Total non-covered loans and loans held for sale, gross			679,220
Consumer | Other Consumer
Aging analysis of past Due non-covered loans and loans held for sale
Accruing loans 30 - 59 days past due	2,154		293
Accruing loans 60 - 89 days past due	162		1
Total accruing past due loans	2,316		294
Nonaccrual loans less than 90 days past due	115		175
Nonaccrual loans 90 or more days past due	540		1,263
Total nonaccrual past due loans	655		1,438
Current Accruing loans	1,453,672		866,786
Total non-covered loans and loans held for sale, gross	$1,456,643		$868,518
[1]	Loans net of ASC 310-30 discount.

NONCOVERED_LOANS_AND_ALLOWANCE7

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 6) (Non-covered loans, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
	item
Troubled debt restructuring disclosures
Number of notes into which A/B notes are split	2
CRE
Troubled debt restructuring disclosures
Loan balance of restructured loans	8,600	$17,500	$9,200
C&I
Troubled debt restructuring disclosures
Loan balance of restructured loans	3,200	15,600	5,000
Residential
Troubled debt restructuring disclosures
Loan balance of restructured loans	12,000	1,100	33,700
Consumer
Troubled debt restructuring disclosures
Loan balance of restructured loans	504	$639	$108

NONCOVERED_LOANS_AND_ALLOWANCE8

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 7) (Non-covered loans, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
	contract		contract		contract
CRE | Land
Restructured loans disclosures
Number of contracts modified as TDRs					3
Pre-Modification Outstanding Recorded Balance					$1,610
Post-Modification Outstanding Recorded Balance					1,059	[1]
Financial Impact					395	[2]
CRE | Income producing
Restructured loans disclosures
Number of contracts modified as TDRs	6		6		8
Pre-Modification Outstanding Recorded Balance	8,829		26,021		10,118
Post-Modification Outstanding Recorded Balance	8,624	[1]	17,456	[1]	8,162	[1]
Financial Impact	43	[2]	219	[2]	1,169	[2]
C&I | Commercial business
Restructured loans disclosures
Number of contracts modified as TDRs	13		6		14
Pre-Modification Outstanding Recorded Balance	4,379		16,220		5,101
Post-Modification Outstanding Recorded Balance	3,089	[1]	15,624	[1]	4,374	[1]
Financial Impact	2,205	[2]	4,274	[2]	560	[2]
C&I | Trade finance
Restructured loans disclosures
Number of contracts modified as TDRs	1				2
Pre-Modification Outstanding Recorded Balance	190				2,510
Post-Modification Outstanding Recorded Balance	73	[1]			579	[1]
Financial Impact	14	[2]			1,506	[2]
Residential | Single-family
Restructured loans disclosures
Number of contracts modified as TDRs	9				12
Pre-Modification Outstanding Recorded Balance	11,454				6,227
Post-Modification Outstanding Recorded Balance	8,269	[1]			5,556	[1]
Financial Impact					938	[2]
Residential | Multifamily
Restructured loans disclosures
Number of contracts modified as TDRs	6		1		16
Pre-Modification Outstanding Recorded Balance	5,471		1,093		28,736
Post-Modification Outstanding Recorded Balance	3,705	[1]	1,071	[1]	28,153	[1]
Financial Impact	7	[2]			3,344	[2]
Consumer | Other Consumer
Restructured loans disclosures
Number of contracts modified as TDRs	1		1		1
Pre-Modification Outstanding Recorded Balance	509		651		108
Post-Modification Outstanding Recorded Balance	$504	[1]	$639	[1]	$108	[1]
[1]	Includes subsequent payments after modification.
[2]	The financial impact includes charge-offs and specific reserves recorded at modification date.

NONCOVERED_LOANS_AND_ALLOWANCE9

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 8) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
	contract	contract	contract
Disclosures on loans modified as TDRs that subsequently defaulted
Period beyond which a TDR generally becomes delinquent	90 days
CRE | Income producing | Non-covered loans
Disclosures on loans modified as TDRs that subsequently defaulted
Number of contracts modified as TDRs that subsequently defaulted			1
Balance of loans modified as TDRs that subsequently defaulted			$271
C&I | Commercial business | Non-covered loans
Disclosures on loans modified as TDRs that subsequently defaulted
Number of contracts modified as TDRs that subsequently defaulted	1	1	2
Balance of loans modified as TDRs that subsequently defaulted	957	570	33
Residential | Single-family | Non-covered loans
Disclosures on loans modified as TDRs that subsequently defaulted
Number of contracts modified as TDRs that subsequently defaulted			2
Balance of loans modified as TDRs that subsequently defaulted			2,830
Residential | Multifamily | Non-covered loans
Disclosures on loans modified as TDRs that subsequently defaulted
Number of contracts modified as TDRs that subsequently defaulted			1
Balance of loans modified as TDRs that subsequently defaulted			378
Consumer | Other Consumer | Non-covered loans
Disclosures on loans modified as TDRs that subsequently defaulted
Number of contracts modified as TDRs that subsequently defaulted		1
Balance of loans modified as TDRs that subsequently defaulted		$639

Recovered_Sheet1

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 9) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restructured loans disclosures
Period for which restructured loans remains on nonaccrual status, to demonstrate that the borrower can perform under the restructured terms	6 months
Non-covered loans
Restructured loans disclosures
Period for which restructured loans remains on nonaccrual status, to demonstrate that the borrower can perform under the restructured terms	6 months
Performing loan | Non-covered loans
Restructured loans disclosures
Loan balance of restructured loans	68,300	$71,800
Performing loan | A/B Note Splits | Non-covered loans
Restructured loans disclosures
Loan balance of restructured loans	2,900	4,300
Nonperforming loan | Non-covered loans
Restructured loans disclosures
Loan balance of restructured loans	20,700	11,100
CRE | Non-covered loans
Restructured loans disclosures
Loan balance of restructured loans	8,600	17,500	9,200
CRE | Performing loan | Non-covered loans
Restructured loans disclosures
Loan balance of restructured loans	28,400	37,600
CRE | Nonperforming loan | Non-covered loans
Restructured loans disclosures
Loan balance of restructured loans	8,200	3,400
C&I | Non-covered loans
Restructured loans disclosures
Loan balance of restructured loans	3,200	15,600	5,000
C&I | Performing loan | Non-covered loans
Restructured loans disclosures
Loan balance of restructured loans	16,200	16,700
C&I | Nonperforming loan | Non-covered loans
Restructured loans disclosures
Loan balance of restructured loans	5,500	3,500
Residential | Non-covered loans
Restructured loans disclosures
Loan balance of restructured loans	12,000	1,100	33,700
Residential | Performing loan | Non-covered loans
Restructured loans disclosures
Loan balance of restructured loans	22,500	17,400
Residential | Nonperforming loan | Non-covered loans
Restructured loans disclosures
Loan balance of restructured loans	7,000	3,600
Consumer | Non-covered loans
Restructured loans disclosures
Loan balance of restructured loans	504	639	108
Consumer | Performing loan | Non-covered loans
Restructured loans disclosures
Loan balance of restructured loans	1,200	108
Consumer | Nonperforming loan | Non-covered loans
Restructured loans disclosures
Loan balance of restructured loans	0	$639

Recovered_Sheet2

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 10) (Non-covered loans, USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Performing loan
Restructured loans disclosures
Allowance for troubled debt restructurings loans receivable	$13,100	$13,000
Nonperforming loan
Restructured loans disclosures
Allowance for troubled debt restructurings loans receivable	$1,900	$836

Recovered_Sheet3

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 11) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Non-covered loans
Impaired loans disclosures
Unpaid principal balance	$177,381,000	$212,637,000
Recorded Investment With No Allowance	82,465,000	110,004,000
Recorded Investment With Allowance	71,655,000	73,473,000
Recorded investment	154,120,000	183,477,000	[1]
Related allowance	19,464,000	24,143,000
Average recorded investment	161,729,000	185,440,000
Interest income recognized (accrual basis)	3,614,000	4,730,000	[2]
Covered loans accounted for under ASC 310-10
Impaired loans disclosures
Covered nonaccrual loans	10,100,000	17,700,000
CRE | Income producing | Non-covered loans
Impaired loans disclosures
Unpaid principal balance	57,805,000	73,777,000
Recorded Investment With No Allowance	34,399,000	39,745,000
Recorded Investment With Allowance	15,646,000	25,523,000
Recorded investment	50,045,000	65,268,000	[1]
Related allowance	1,581,000	5,976,000
Average recorded investment	54,544,000	71,856,000
Interest income recognized (accrual basis)	1,249,000	2,480,000
CRE | Construction | Non-covered loans
Impaired loans disclosures
Unpaid principal balance	6,888,000	6,888,000
Recorded Investment With No Allowance	6,888,000	6,888,000
Recorded investment	6,888,000	6,888,000	[1]
Average recorded investment	6,888,000	6,888,000
CRE | Land | Non-covered loans
Impaired loans disclosures
Unpaid principal balance	13,291,000	17,390,000
Recorded Investment With No Allowance	2,838,000	4,372,000
Recorded Investment With Allowance	5,622,000	7,908,000
Recorded investment	8,460,000	12,280,000	[1]
Related allowance	1,906,000	2,082,000
Average recorded investment	8,633,000	12,453,000
Interest income recognized (accrual basis)	298,000	496,000	[2]
C&I | Commercial business | Non-covered loans
Impaired loans disclosures
Unpaid principal balance	42,396,000	48,482,000
Recorded Investment With No Allowance	10,552,000	10,850,000
Recorded Investment With Allowance	25,717,000	27,487,000
Recorded investment	36,269,000	38,337,000	[1]
Related allowance	15,174,000	13,787,000
Average recorded investment	36,528,000	38,294,000
Interest income recognized (accrual basis)	833,000	735,000	[2]
C&I | Trade finance | Non-covered loans
Impaired loans disclosures
Unpaid principal balance	280,000	2,771,000
Recorded Investment With No Allowance		438,000
Recorded Investment With Allowance	274,000	752,000
Recorded investment	274,000	1,190,000	[1]
Related allowance	28,000	752,000
Average recorded investment	336,000	1,603,000
Interest income recognized (accrual basis)	15,000	11,000	[2]
Residential | Single-family | Non-covered loans
Impaired loans disclosures
Unpaid principal balance	17,838,000	15,814,000
Recorded Investment With No Allowance	5,137,000	13,585,000
Recorded Investment With Allowance	11,398,000	1,588,000
Recorded investment	16,535,000	15,173,000	[1]
Related allowance	461,000	207,000
Average recorded investment	16,413,000	15,322,000
Interest income recognized (accrual basis)	342,000	154,000	[2]
Residential | Multifamily | Non-covered loans
Impaired loans disclosures
Unpaid principal balance	37,624,000	43,821,000
Recorded Investment With No Allowance	21,500,000	30,899,000
Recorded Investment With Allowance	12,890,000	10,215,000
Recorded investment	34,390,000	41,114,000	[1]
Related allowance	313,000	1,339,000
Average recorded investment	37,128,000	35,799,000
Interest income recognized (accrual basis)	830,000	850,000	[2]
Consumer | Student loans | Non-covered loans
Impaired loans disclosures
Unpaid principal balance		1,749,000
Recorded Investment With No Allowance		1,681,000
Recorded investment		1,681,000	[1]
Average recorded investment		1,664,000
Consumer | Other Consumer | Non-covered loans
Impaired loans disclosures
Unpaid principal balance	1,259,000	1,945,000
Recorded Investment With No Allowance	1,151,000	1,546,000
Recorded Investment With Allowance	108,000
Recorded investment	1,259,000	1,546,000	[1]
Related allowance	1,000
Average recorded investment	1,259,000	1,561,000
Interest income recognized (accrual basis)	$47,000	$4,000	[2]
[1]	Excludes $10.1 million and $17.7 million of covered non-accrual loans as of December 31, 2014 and December 31, 2013, respectively, accounted for under ASC 310-10, of which some loans have additional partial balances accounted for under ASC 310-30.
[2]	Includes interest recognized on accruing TDRs. Interest payments received on nonaccrual loans are reflected as a reduction of principal and not as interest income.

Recovered_Sheet4

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 12) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012
Financing Receivable Allowance for Credit Losses Roll Forward
Provision for (reversal of) loan losses	$49,158		$22,364	$65,184
Non-covered loans
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	241,930		229,382	209,876
Allowance for unfunded loan commitments and letters of credit	-1,575		-2,157	1,563
Provision for (reversal of) loan losses	44,125		18,336	60,168
Charge-offs	-39,782		-16,344	-58,402
Recoveries	13,476		12,713	16,177
Net (charge-offs) recoveries	-26,306		-3,631	-42,225
Ending balance	258,174		241,930	229,382
Ending balance allocated to:
Loans individually evaluated for impairment	19,464		24,143	11,527
Loans collectively evaluated for impairment	238,420		217,787	217,855
Acquired with deteriorated credit quality	290
Ending balance	258,174		241,930	229,382
Non-covered loans | MetroCorp
Financing Receivable Allowance for Credit Losses Roll Forward
Charge-offs	-523
CRE | Non-covered loans
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	64,677		69,856	66,457
Provision for (reversal of) loan losses	6,107		-6,615	20,977
Charge-offs	-3,294	[1]	-3,357	-27,060
Recoveries	1,982		4,793	9,482
Net (charge-offs) recoveries	-1,312		1,436	-17,578
Ending balance	69,472		64,677	69,856
Ending balance allocated to:
Loans individually evaluated for impairment	3,487		8,058	5,561
Loans collectively evaluated for impairment	65,695		56,619	64,295
Acquired with deteriorated credit quality	290
Ending balance	69,472		64,677	69,856
C&I | Non-covered loans
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	115,184		105,376	87,020
Provision for (reversal of) loan losses	40,371		12,821	35,204
Charge-offs	-29,592		-7,405	-21,818
Recoveries	8,635		4,392	4,970
Net (charge-offs) recoveries	-20,957		-3,013	-16,848
Ending balance	134,598		115,184	105,376
Ending balance allocated to:
Loans individually evaluated for impairment	15,202		14,539	2,835
Loans collectively evaluated for impairment	119,396		100,645	102,541
Ending balance	134,598		115,184	105,376
Residential | Non-covered loans
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	50,717		49,349	52,180
Provision for (reversal of) loan losses	-8,168		1,918	3,255
Charge-offs	-1,103		-3,197	-7,700
Recoveries	2,410		2,647	1,614
Net (charge-offs) recoveries	1,307		-550	-6,086
Ending balance	43,856		50,717	49,349
Ending balance allocated to:
Loans individually evaluated for impairment	774		1,546	3,131
Loans collectively evaluated for impairment	43,082		49,171	46,218
Ending balance	43,856		50,717	49,349
Consumer | Non-covered loans
Financing Receivable Allowance for Credit Losses Roll Forward
Beginning balance	11,352		4,801	4,219
Provision for (reversal of) loan losses	4,240		8,055	2,295
Charge-offs	-5,793		-2,385	-1,824
Recoveries	449		881	111
Net (charge-offs) recoveries	-5,344		-1,504	-1,713
Ending balance	10,248		11,352	4,801
Ending balance allocated to:
Loans individually evaluated for impairment	1
Loans collectively evaluated for impairment	10,247		11,352	4,801
Ending balance	10,248		11,352	4,801
Unallocated | Non-covered loans
Financing Receivable Allowance for Credit Losses Roll Forward
Allowance for unfunded loan commitments and letters of credit	-1,575		-2,157	1,563
Provision for (reversal of) loan losses	$1,575		$2,157	($1,563)
[1]	Includes a charge-off of $523 thousand related to PCI loans acquired from MetroCorp.

Recovered_Sheet5

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 13) (Non-covered loans, USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Recorded investment in total loans receivable related to each balance in the allowance for loan losses
Individually evaluated for impairment	$154,120	$183,477
Collectively evaluated for impairment	19,997,601	15,494,840
Acquired with deteriorated credit quality	97,730
Ending balance	20,249,451	15,678,317
CRE
Recorded investment in total loans receivable related to each balance in the allowance for loan losses
Individually evaluated for impairment	65,393	84,436
Collectively evaluated for impairment	5,977,437	4,500,641
Acquired with deteriorated credit quality	91,216
Ending balance	6,134,046	4,585,077
C&I
Recorded investment in total loans receivable related to each balance in the allowance for loan losses
Individually evaluated for impairment	36,543	39,527
Collectively evaluated for impairment	7,796,239	5,320,666
Acquired with deteriorated credit quality	5,312
Ending balance	7,838,094	5,360,193
Residential
Recorded investment in total loans receivable related to each balance in the allowance for loan losses
Individually evaluated for impairment	50,925	56,287
Collectively evaluated for impairment	4,768,541	4,129,022
Acquired with deteriorated credit quality	1,202
Ending balance	4,820,668	4,185,309
Consumer
Recorded investment in total loans receivable related to each balance in the allowance for loan losses
Individually evaluated for impairment	1,259	3,227
Collectively evaluated for impairment	1,455,384	1,544,511
Acquired with deteriorated credit quality	0
Ending balance	$1,456,643	$1,547,738

Recovered_Sheet6

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 14) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Allowance for Unfunded Loan Commitments, Off-Balance Sheet Credit Exposures and Recourse Provisions
Allowance for unfunded loan commitments, off-balance sheet credit exposures and recourse provision	$12,700,000	$11,300,000
Non-covered loans
Allowance for Unfunded Loan Commitments, Off-Balance Sheet Credit Exposures and Recourse Provisions
Allowance for unfunded loan commitments, off-balance sheet credit exposures and recourse provision	12,700,000	11,300,000
Off-balance sheet loans serviced for others	1,190,000,000	1,350,000,000
Portion of allowance for unfunded loan commitments, off-balance sheet credit exposures and recourse provisions related to off-balance sheet loans sold and securitized	$2,200,000	$3,200,000

Recovered_Sheet7

NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 15) (Non-covered loans, MetroCorp, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014
Non-covered loans | MetroCorp
Changes in the accretable yield for the PCI loans
Additions	$6,745
Accretion	-4,960
Changes in expected cash flows	3,379
Ending Balance	$5,164

AFFORDABLE_HOUSING_PARTNERSHIP1

AFFORDABLE HOUSING PARTNERSHIPS AND OTHER TAX CREDIT INVESTMENTS (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
AFFORDABLE HOUSING PARTNERSHIPS AND OTHER TAX CREDIT INVESTMENTS
Minimum compliance period to fully utilize the tax credits	15 years
Investment in affordable housing partnerships, net	$178,652,000	$164,776,000
CRA and other tax credit investments	110,100,000	70,200,000
Total unfunded commitments for investments	114,700,000	73,100,000
Affordable housing partnerships and other tax credits	84,800,000	34,200,000	18,700,000
Amortization of investments in affordable housing partnerships and other tax credit investments	75,660,000	27,268,000	18,058,000
Remaining tax credits	$193,800,000

GOODWILL_AND_OTHER_INTANGIBLE_2

GOODWILL AND OTHER INTANGIBLE ASSETS (Details) (USD $)	0 Months Ended	12 Months Ended				3 Months Ended
	Jan. 17, 2014	Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014
		item
Premiums on Acquired Deposits
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		8 years
Amortization of premiums on deposits acquired		$10,204,000		$9,365,000	$10,906,000
Goodwill		469,433,000		337,438,000	337,438,000	469,433,000
Increase in goodwill	132,000,000
Number of business divisions		3
Number of operating segments		3
Period for which the company provided a net income projection under the income approach to determine the fair value of the reporting units		3 years
Goodwill impairment		0
Changes in carrying amount of goodwill
Beginning balance		337,438,000		337,438,000
Additions from the MetroCorp acquisition		131,995,000	[1]
Ending Balance		469,433,000		337,438,000	337,438,000	469,433,000
Estimated Future Amortization Expense of Premiums on Acquired Deposits
2015		9,234,000				9,234,000
2016		8,086,000				8,086,000
2017		6,935,000				6,935,000
2018		5,883,000				5,883,000
2019		4,864,000				4,864,000
Thereafter		10,307,000				10,307,000
Total		45,309,000				45,309,000
MetroCorp
Premiums on Acquired Deposits
Intangible recorded due to the acquisition of MetroCorp	8,600,000
Additional tax adjustment in connection with a business combination		11,000,000				11,000,000
Goodwill	121,000,000	132,000,000				132,000,000
Changes in carrying amount of goodwill
Beginning balance	121,000,000
Ending Balance	121,000,000	132,000,000				132,000,000
Premiums on acquired deposits
Premiums on Acquired Deposits
Gross carrying amount of premiums on acquired deposits		108,800,000		100,200,000		108,800,000
Accumulated amortization for premiums on acquired deposits		63,500,000		53,300,000		63,500,000
Amortization of premiums on deposits acquired		10,200,000		9,400,000	10,900,000
Premiums on acquired deposits | MetroCorp
Premiums on Acquired Deposits
Intangible recorded due to the acquisition of MetroCorp	$8,600,000
[1]	Includes $11.0 million of deferred tax adjustments recorded in the fourth quarter of 2014.

CUSTOMER_DEPOSIT_ACCOUNTS_Deta

CUSTOMER DEPOSIT ACCOUNTS (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Customer deposit account balances
Noninterest-bearing demand	$7,381,030,000	$5,821,899,000
Interest-bearing checking	2,545,618,000	1,749,479,000
Money market accounts	6,318,120,000	5,653,412,000
Savings deposits	1,651,267,000	1,363,780,000
Total core deposits	17,896,035,000	14,588,570,000
Time deposits:
Less than $100,000	1,662,046,000	1,678,850,000
$100,000 or greater	4,450,693,000	4,145,498,000
Total time deposits	6,112,739,000	5,824,348,000
Total deposits	24,008,774,000	20,412,918,000
Time deposits $100 thousand or greater held by the Company's foreign branch located in Hong Kong	$133,300,000	$169,700,000

CUSTOMER_DEPOSIT_ACCOUNTS_Deta1

CUSTOMER DEPOSIT ACCOUNTS (Details 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Scheduled maturities of time deposits, $100,000 or Greater
2015	$3,513,958
2016	318,791
2017	189,195
2018	168,252
2019	142,492
Thereafter	118,005
Total	4,450,693	4,145,498
Scheduled maturities of time deposits, Less than $100,000
2015	1,397,648
2016	164,061
2017	44,944
2018	34,579
2019	20,782
Thereafter	32
Total	1,662,046	1,678,850
Total
2015	4,911,606
2016	482,852
2017	234,139
2018	202,831
2019	163,274
Thereafter	118,037
Total time deposits	$6,112,739	$5,824,348

CUSTOMER_DEPOSIT_ACCOUNTS_Deta2

CUSTOMER DEPOSIT ACCOUNTS (Details 3) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Time deposits:
Time deposits within the Certificate of Deposit Account Registry Service (CDARS) program	$180	$203.30

FEDERAL_HOME_LOAN_BANK_ADVANCE2

FEDERAL HOME LOAN BANK ADVANCES AND LONG-TERM DEBT (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Advances from FHLB
Total outstanding FHLB advances	$317,241,000	$315,092,000
Weighted average interest rates (as a percent)	0.58%	0.61%
Maturities in 2015	0
Maturities in 2016	0
Maturities in 2017	0
Maturities in 2018	0
Maturities in 2019	79,400,000
Maturities in 2020 and after	237,800,000
Interest rate, low end of range (as a percent)	0.40%
Interest rate, high end of range (as a percent)	0.64%
Outstanding overnight FHLB borrowings	$0	$0

FEDERAL_HOME_LOAN_BANK_ADVANCE3

FEDERAL HOME LOAN BANK ADVANCES AND LONG-TERM DEBT (Details 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Billions, unless otherwise specified
FEDERAL HOME LOAN BANK ADVANCES AND LONG-TERM DEBT
Available borrowing capacity from unused FHLB advances	$5.54	$3.70
Additional available borrowing capacity from the Federal Reserve Bank's discount window	$3.03	$1.42

FEDERAL_HOME_LOAN_BANK_ADVANCE4

FEDERAL HOME LOAN BANK ADVANCES AND LONG-TERM DEBT (Details 3) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Capital Resources
Long-term Debt	$225,848	$226,868
Junior Subordinated Debt
Capital Resources
Long-term Debt	145,848	126,868
Term loan
Capital Resources
Long-term Debt	$80,000	$100,000

FEDERAL_HOME_LOAN_BANK_ADVANCE5

FEDERAL HOME LOAN BANK ADVANCES AND LONG-TERM DEBT (Details 4) (USD $)	12 Months Ended			0 Months Ended	3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2014	Sep. 30, 2013
Capital Resources
Minimum total consolidated assets for exclusion of trust preferred securities as Tier I regulatory capital	$15,000,000,000
Debt redeemed	30,310,000	10,310,000	75,000,000
Long-term debt	225,848,000	226,868,000
Junior Subordinated Debt
Capital Resources
Number of statutory business trusts formed for the purpose of issuing junior subordinated debt to third party investors	6
Number of junior subordinated debts called	1
Common stock issued by the Trusts to the Company	4,600,000	3,900,000
Minimum total consolidated assets for exclusion of trust preferred securities as Tier I regulatory capital	15,000,000,000
Debt instrument, phased out (as a percent)		25.00%
Debt instrument, phased out period		4 years
Stated Interest Rate, base	three-month LIBOR
Balance at the end of the period	148,000,000	123,000,000
Long-term debt	145,848,000	126,868,000
Term loan
Capital Resources
Stated Interest Rate, base	three-month LIBOR
Stated Interest Rate, basis spread (as a percent)	1.50%
Interest rate as of reporting date (as a percent)	1.81%
Issue of debt					100,000,000
Maturity period of debt					3 years
Quarterly installment				5,000,000
Final, lump sum repayment at maturity of debt instrument	50,000,000
Long-term debt	80,000,000	100,000,000
East West Capital Trust IV | Junior Subordinated Debt
Capital Resources
Stated Interest Rate, base	3-month Libor +
Stated Interest Rate, basis spread (as a percent)	2.55%
Balance at the end of the period		10,000,000
Debt redeemed	10,000,000
Stock redeemed	310,000
East West Capital Trust V | Junior Subordinated Debt
Capital Resources
Stated Interest Rate, base	3-month Libor +
Stated Interest Rate, basis spread (as a percent)	1.80%
Interest rate as of reporting date (as a percent)	2.03%
Balance at the end of the period	15,000,000	15,000,000
East West Capital Trust VI | Junior Subordinated Debt
Capital Resources
Stated Interest Rate, base	3-month Libor +
Stated Interest Rate, basis spread (as a percent)	1.50%
Interest rate as of reporting date (as a percent)	1.74%
Balance at the end of the period	20,000,000	20,000,000
East West Capital Trust VII | Junior Subordinated Debt
Capital Resources
Stated Interest Rate, base	3-month Libor +
Stated Interest Rate, basis spread (as a percent)	1.35%
Interest rate as of reporting date (as a percent)	1.59%
Balance at the end of the period	30,000,000	30,000,000
East West Capital Trust VIII | Junior Subordinated Debt
Capital Resources
Stated Interest Rate, base	3-month Libor +
Stated Interest Rate, basis spread (as a percent)	1.40%
Interest rate as of reporting date (as a percent)	1.64%
Balance at the end of the period	18,000,000	18,000,000
East West Capital Trust IX | Junior Subordinated Debt
Capital Resources
Stated Interest Rate, base	3-month Libor +
Stated Interest Rate, basis spread (as a percent)	1.90%
Interest rate as of reporting date (as a percent)	2.14%
Balance at the end of the period	30,000,000	30,000,000
Metro Bank Trust | Junior Subordinated Debt
Capital Resources
Reduction of a purchase accounting adjustment	6,800,000
Common stock issued by the Trusts to the Company	1,100,000
Stated Interest Rate, base	3-month Libor +
Stated Interest Rate, basis spread (as a percent)	1.55%
Interest rate as of reporting date (as a percent)	1.79%
Balance at the end of the period	$35,000,000

INCOME_TAXES_Details

INCOME TAXES (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
INCOME TAXES
Tax credits generated from investments in affordable housing partnerships and other investments									$85,700,000	$35,000,000	$18,700,000
Net deferred tax assets	384,367,000				255,530,000				384,367,000	255,530,000
Current income tax expense (benefit):
Federal									153,211,000	131,236,000	148,572,000
State									70,527,000	44,389,000	2,316,000
Foreign									3,846,000	208,000	5,704,000
Total current income tax expense (benefit)									227,584,000	175,833,000	156,592,000
Deferred income tax (benefit) expense:
Federal									-116,241,000	-32,963,000	-38,749,000
State									-37,665,000	-13,677,000	26,099,000
Foreign									-706,000	1,612,000
Total deferred income tax (benefit) expense									-154,612,000	-45,028,000	-12,650,000
Provision for income taxes	$20,049,000	($13,644,000)	$31,618,000	$34,949,000	$22,782,000	$35,749,000	$37,855,000	$34,419,000	$72,972,000	$130,805,000	$143,942,000
Difference between the effective tax rate implicit in the consolidated financial statements and the statutory federal income tax rate
Federal income tax provision at statutory rate (as a percent)									35.00%	35.00%	35.00%
State franchise taxes, net of federal tax effect (as a percent)									5.10%	4.70%	4.30%
Tax credits (as a percent)									-21.50%	-8.40%	-5.30%
Other, net (as a percent)									-1.00%	-0.60%	-0.20%
Effective income tax rate (as a percent)									17.60%	30.70%	33.80%

INCOME_TAXES_Details_2

INCOME TAXES (Details 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Deferred tax liabilities:
Core deposit intangibles	($20,261)	($21,064)
Affordable housing partnership and other investments		-15,888
Fixed assets	-20,716	-19,473
Federal Housing Loan Bank stock	-6,539	-14,561
Deferred loan fees	-2,041	-2,533
Purchased loan discounts	-66	-126
State taxes	-8,244	-1,079
Section 597 gain	-2,127	-49,687
FDIC receivable		-252,602
Acquired debt	-868	-11,854
Other, net	-2,125	-5,882
Total gross deferred tax (liabilities)	-62,987	-394,749
Deferred tax assets:
Affordable housing partnerships and other investments	6,638
Allowance for loan losses and REO reserves	118,773	116,064
FDIC receivable and clawback	48,366
Deferred compensation	21,290	17,146
Mortgage servicing assets	3,305	368
Purchased loan premium	376	544
Unrealized loss on securities	55,375	81,712
Acquired loans and REOs	176,294	394,208
Other, net	17,253	40,574
Total gross deferred tax assets	447,670	650,616
Valuation allowance	-316	-337
Net deferred tax assets	384,367	255,530
Federal
Deferred tax liabilities:
Core deposit intangibles	-15,748	-16,422
Affordable housing partnership and other investments		-14,158
Fixed assets	-16,615	-15,594
Federal Housing Loan Bank stock	-5,064	-11,337
Deferred loan fees	-1,587	-1,976
Purchased loan discounts	-51	-98
State taxes	-8,244	-1,079
Section 597 gain	-2,063	-48,370
FDIC receivable		-245,907
Acquired debt	-2,237	-10,812
Other, net	-1,652	-6,805
Total gross deferred tax (liabilities)	-53,261	-372,558
Deferred tax assets:
Affordable housing partnerships and other investments	1,768
Allowance for loan losses and REO reserves	93,749	93,018
FDIC receivable and clawback	36,630
Deferred compensation	16,505	13,322
Mortgage servicing assets	2,570	287
Purchased loan premium	292	424
Unrealized loss on securities	42,737	62,535
Acquired loans and REOs	139,360	366,290
Other, net	12,189	30,768
Total gross deferred tax assets	345,800	566,644
Net deferred tax assets	292,539	194,086
State
Deferred tax liabilities:
Core deposit intangibles	-4,513	-4,642
Affordable housing partnership and other investments		-1,730
Fixed assets	-4,101	-3,879
Federal Housing Loan Bank stock	-1,475	-3,224
Deferred loan fees	-454	-557
Purchased loan discounts	-15	-28
Section 597 gain	-64	-1,317
FDIC receivable		-6,695
Acquired debt	1,369	-1,042
Other, net	-473	923
Total gross deferred tax (liabilities)	-9,726	-22,191
Deferred tax assets:
Affordable housing partnerships and other investments	4,870
Allowance for loan losses and REO reserves	23,615	23,046
FDIC receivable and clawback	11,736
Deferred compensation	4,785	3,824
Mortgage servicing assets	735	81
Purchased loan premium	84	120
Unrealized loss on securities	12,638	19,177
Acquired loans and REOs	36,678	26,959
Other, net	4,967	9,709
Total gross deferred tax assets	100,108	82,916
Valuation allowance	-316	-337
Net deferred tax assets	90,066	60,388
Foreign
Deferred tax assets:
Allowance for loan losses and REO reserves	1,409
Acquired loans and REOs	256	959
Other, net	97	97
Total gross deferred tax assets	1,762	1,056
Net deferred tax assets	$1,762	$1,056

INCOME_TAXES_Details_3

INCOME TAXES (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
INCOME TAXES
Net operating loss carryforwards	$4,000,000
Activity related to unrecognized tax benefits
Ending Balance	4,677,000	3,457,000
Additions for tax positions of prior years	343,000	232,000
Additions for tax positions of current year		988,000
Beginning Balance	5,020,000	4,677,000
Increase in unrecognized tax benefits reserve for the California enterprise zone net interest deduction	343,000	1,200,000
Reduction in unrecognized tax benefits reserve for California enterprise zone, net interest deduction	0
ASC 740-10 liability	7,200,000	6,300,000
Total amount of unrecognized tax benefits that, if recognized, would impact the effective tax rate	3,300,000	3,000,000
Accrued interest and penalties expense for unrecognized tax positions	597,000	-744,000	1,200,000
Total interest and penalties accrued	$2,200,000	$1,600,000

COMMITMENTS_AND_CONTINGENCIES_1

COMMITMENTS AND CONTINGENCIES (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Credit Extensions
Allowance for unfunded loan commitments, off-balance sheet credit exposures and recourse provision	$12,700,000	$11,300,000
Undisbursed Loan Commitments
Credit Extensions
Loan	3,870,000,000	4,020,000,000
Commercial and Standby Letters of Credit
Credit Extensions
Commercial and standby letters of credit issued	$1,250,000,000	$1,160,000,000

COMMITMENTS_AND_CONTINGENCIES_2

COMMITMENTS AND CONTINGENCIES (Details 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 18, 2014
In Millions, unless otherwise specified
Other Commitments
Other Commitments	$114.70	$73.10
Loans Sold or Securitized with Recourse
Guarantees
Principal amount of single-family loans with full recourse sold or securitized	35.5	42.2
Principal amount of multifamily loans with limited recourse sold or securitized	214.3	296.6
Principal amount of loans sold or securitized	249.8	338.8
Recourse provision limitation, maximum percentage of the top loss on the multifamily loans	4.00%
Recourse reserve related to loan sales and securitizations totaled	2.2	3.2
Commitment to repurchase the loan	0
Loans Sold without Recourse
Guarantees
Principal amount of loans sold or securitized	781.4	818.2
Loans Securitized without Recourse
Guarantees
Principal amount of loans sold or securitized	162.8	193.8
F&F, LLC and 618 Investment, Inc. v. East West Bank
Litigation
Interim adjusted amount of the verdict			36.6
East West Bank | F&F, LLC and 618 Investment, Inc. v. East West Bank
Litigation
Litigation accrual	$31.60

COMMITMENTS_AND_CONTINGENCIES_3

COMMITMENTS AND CONTINGENCIES (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Lease Commitments
Rental expense	$26,200,000	$26,200,000	$22,800,000
Estimated future minimum rental payments under non-cancelable operating leases
2015	24,076,000
2016	19,239,000
2017	14,957,000
2018	11,389,000
2019	9,950,000
Thereafter	30,910,000
Total	$110,521,000

STOCK_COMPENSATION_PLANS_Detai

STOCK COMPENSATION PLANS (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Summary of Stock-based Compensation Plans
Total compensation expense, before taxes	$13,900,000	$13,500,000	$12,700,000
Net tax benefit recognized in equity for stock compensation plans	6,513,000	5,522,000	462,000
Incentive shares available to be issued	3,715,327
Stock Options
Summary of Stock-based Compensation Plans
Cash proceeds from stock option exercises	4,900,000	1,700,000
Net tax benefit recognized in equity for stock compensation plans	$1,400,000	$48,000

STOCK_COMPENSATION_PLANS_Detai1

STOCK COMPENSATION PLANS (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stock purchase plan
Compensation expense recognized	$13,900,000	$13,500,000	$12,700,000
Shares available under the Purchase Plan	3,715,327
Stock Options
Summary of stock option activity
Outstanding at beginning of year (in shares)	406,731
Exercised (in shares)	-234,101
Forfeited (in shares)	-130,514
Outstanding at end of year (in shares)	42,116	406,731
Vested or expected to vest at year-end (in shares)	42,116
Exercisable at year-end	42,116
Outstanding at beginning of year, weighted average exercise price (in dollars per share)	$26.72
Exercised, weighted average exercise price (in dollars per share)	$21.09
Forfeited, weighted average exercise price (in dollars per share)	$38.76
Outstanding at end of year, weighted average exercise price (in dollars per share)	$20.75	$26.72
Vested or expected to vest at year-end, weighted average exercise price (in dollars per share)	$20.75
Exercisable at end year-end, weighted average exercise price (in dollars per share)	$20.75
Outstanding at end of year, weighted average remaining term	2 months 8 days
Vested or expected to vest at end of year, weighted average remaining term	2 months 8 days
Exercisable at end of year, weighted average remaining term	2 months 8 days
Outstanding at end of year, aggregate intrinsic value	757,000
Vested or expected to vest at year-end, aggregate intrinsic value	757,000
Exercisable at year-end, aggregate intrinsic value	757,000
Share based compensation plan, additional disclosures
Total intrinsic value of options exercised (in thousands)	3,546,000	926,000	978,000
Total fair value of options vested (in thousands)		363,000	3,717,000
Stock Options | Minimum
Stock Options
Vesting period	3 years
Contractual term of stock option grants	7 years
Stock Options | Maximum
Stock Options
Vesting period	4 years
Contractual term of stock option grants	10 years
Stock Purchase Plan
Stock purchase plan
Purchase price of shares in terms compared to market price per share (as a percent)	90.00%
Value of shares sold to employees under purchase plan	25,000
Compensation expense recognized	0
Common stock, shares authorized (in shares)	2,000,000
Shares sold to employees under purchase plan (in shares)	58,587	53,015
Stock Issued During Period, Value, Employee Stock Purchase Plan	$1,900,000	$1,400,000
Shares available under the Purchase Plan	694,713

Recovered_Sheet8

STOCK COMPENSATION Plans (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2014
Range of exercise price per share from $10.00 to $14.99
Stock options outstanding
Range of exercise prices, low end of the range (in dollars per share)	$10
Range of exercise prices, high end of the range (in dollars per share)	$14.99
Options Outstanding
Number of Outstanding Options (in shares)	2,365
Weighted Average Exercise Price (in dollars per share)	$14.95
Weighted Average Remaining Contractual Life	1 year 7 days
Options Exercisable
Number of Exercisable Options (in shares)	2,365
Weighted Average Exercise Price (in dollars per share)	$14.95
Range of exercise price per share from $20.00 to $24.99
Stock options outstanding
Range of exercise prices, low end of the range (in dollars per share)	$20
Range of exercise prices, high end of the range (in dollars per share)	$24.99
Options Outstanding
Number of Outstanding Options (in shares)	39,751
Weighted Average Exercise Price (in dollars per share)	$21.09
Weighted Average Remaining Contractual Life	1 month 21 days
Options Exercisable
Number of Exercisable Options (in shares)	39,751
Weighted Average Exercise Price (in dollars per share)	$21.09
Range of exercise price per share from $10.00 to $24.99
Stock options outstanding
Range of exercise prices, low end of the range (in dollars per share)	$10
Range of exercise prices, high end of the range (in dollars per share)	$24.99
Options Outstanding
Number of Outstanding Options (in shares)	42,116
Weighted Average Exercise Price (in dollars per share)	$20.75
Weighted Average Remaining Contractual Life	2 months 9 days
Options Exercisable
Number of Exercisable Options (in shares)	42,116
Weighted Average Exercise Price (in dollars per share)	$20.75

STOCK_COMPENSATION_PLANS_Detai2

STOCK COMPENSATION PLANS (Details 4) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restricted stock units | Outside Director
Summary of restricted stock awards activity
Granted (in shares)	0
Restricted stock units | Minimum
Summary of Stock-based Compensation Plans
Vesting period	3 years
Restricted stock units | Maximum
Summary of Stock-based Compensation Plans
Vesting period	5 years
Time-based restricted stock awards
Summary of restricted stock awards activity
Outstanding unvested at beginning of year (in shares)	438,508
Granted (in shares)	43,210
Vested (in shares)	-343,722
Forfeited (in shares)	-30,733
Outstanding unvested at end of year (in shares)	107,263	438,508
Outstanding unvested at beginning of year, weighted average price (in dollars per share)	$17.79
Granted, weighted average price (in dollars per share)	$33.19	$28.55	$21.66
Vested, weighted average price (in dollars per share)	$15.91
Forfeited, weighted average price (in dollars per share)	$21.21
Outstanding unvested at end of year, weighted average price (in dollars per share)	$29.01	$17.79
Total fair value of restricted stock awards vested	$12.20	$29.40	$3.50
Total unrecognized stock compensation expense	2.3
Weighted average period to recognize unrecognized compensation cost	2 years 6 months 18 days
Performance-based restricted stock awards
Summary of restricted stock awards activity
Outstanding unvested at beginning of year (in shares)	956,707
Granted (in shares)	603,697
Vested (in shares)	-340,866
Forfeited (in shares)	-57,228
Outstanding unvested at end of year (in shares)	1,162,310	956,707
Outstanding unvested at beginning of year, weighted average price (in dollars per share)	$23.74
Granted, weighted average price (in dollars per share)	$36.85	$25.25	$22.05
Vested, weighted average price (in dollars per share)	$23.52
Forfeited, weighted average price (in dollars per share)	$29.71
Outstanding unvested at end of year, weighted average price (in dollars per share)	$30.32	$23.74
Total fair value of restricted stock awards vested	12.6	4.4	4.7
Total unrecognized stock compensation expense	$21.70
Weighted average period to recognize unrecognized compensation cost	1 year 11 months 5 days

EMPLOYEE_BENEFIT_PLANS_Details

EMPLOYEE BENEFIT PLANS (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plans
Employer's contribution	$5,900,000	$4,300,000	$3,500,000
Supplemental Executive Retirement Plan (SERP)
Defined Benefit Plans
Benefits accrued	583,000	644,000	787,000
Surrender value related to life insurance contracts	$31,400,000	$45,500,000

STOCKHOLDERS_EQUITY_AND_EARNIN2

STOCKHOLDERS' EQUITY AND EARNINGS PER SHARE (Details) (USD $)	12 Months Ended			0 Months Ended		1 Months Ended	3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 17, 2014	1-May-13	Apr. 30, 2008	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Jan. 16, 2014	Jul. 17, 2013	Jan. 23, 2013	Jan. 19, 2012
Class of Stock
Common stock issued on conversion of convertible preferred stock		5,594,080
Final consideration (in shares)	5,583,093
Purchase of treasury stock pursuant to the Stock Repurchase Program, shares		8,026,807	9,068,105
Weighted average price of shares repurchased (in dollars per share)		$24.89	$22.02
Total cost of repurchase of treasury shares		$199,992,000	$199,950,000
Quarterly Dividends
Dividend per share (in dollars per share)	$0.72	$0.60	$0.40
MetroCorp
Class of Stock
Final consideration (in shares)				5,583,093
Final consideration in cash				89,400,000
Fair value of warrants				8,800,000
Cash paid to option holders				2,400,000
Warrants converted into the right to acquire shares																			771,429
Common stock equivalent to assumed obligation of holder's rights unexercised warrant (in shares)				230,282
Number of warrants exercised	0						0
Series A Non-Cumulative Perpetual Convertible Preferred Stock
Class of Stock
Number of shares issued during the period						200,000
Preferred stock dividend rate (as a percent)						8.00%
Preferred stock liquidation preference (in dollars per share)						$1,000
Proceeds from issuance of convertible preferred stock						194,100,000
Preferred shares converted					85,710
Common stock issued on conversion of convertible preferred stock					5,594,080
Quarterly Dividends
Dividend per share (in dollars per share)		$20	$20
Preferred stock cash dividends paid		3,400,000	6,900,000
Common Stock
Class of Stock
Amount of stock repurchase approved by the Board of Directors																				100,000,000	200,000,000	200,000,000
Quarterly Dividends
Dividend per share (in dollars per share)							$0.18	$0.18	$0.18	$0.18	$0.15	$0.15	$0.15	$0.15	$0.10	$0.10	$0.10	$0.10
Common stock cash dividends paid	$104,000,000	$83,300,000	$57,600,000
Common Stock | MetroCorp
Class of Stock
Final consideration (in shares)				5,583,093

STOCKHOLDERS_EQUITY_AND_EARNIN3

STOCKHOLDERS' EQUITY AND EARNINGS PER SHARE (Details 2) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
STOCKHOLDERS' EQUITY AND EARNINGS PER SHARE
Common stock, shares outstanding	143,582,229				137,630,896				143,582,229	137,630,896
Earnings per share calculations
Net income	$92,998	$88,756	$83,988	$76,741	$75,782	$73,157	$74,015	$72,091	$342,483	$295,045	$281,650
Less: Preferred stock dividends							-1,714	-1,714		-3,428	-6,857
Less: Earnings allocated to participating securities									-502	-1,692	-3,279
Basic EPS - income allocated to common stockholders									341,981	289,925	271,514
Effect of dilutive securities:
Restricted stock units									287	196	47
Convertible preferred stock										3,428	6,857
Diluted EPS - income allocated to common stockholders									$342,268	$293,549	$278,418
Number of Shares
Weighted average shares outstanding									142,952,000	137,342,000	141,457,000
Effect of dilutive securities on weighted average shares outstanding
Stock options (in shares)									67,000	71,000	29,000
Restricted stock units (in shares)									398,000	327,000	118,000
Convertible preferred stock (in shares)										1,834,000	5,571,000
Warrants (in shares)									146,000
Total weighted average diluted shares outstanding									143,563,000	139,574,000	147,175,000
Per Share Amounts
Basic EPS - income allocated to common stockholders (in dollars per share)	$0.65	$0.62	$0.59	$0.54	$0.55	$0.53	$0.52	$0.51	$2.39	$2.11	$1.92
Diluted EPS - Income available to common stockholders (in dollars per share)	$0.65	$0.62	$0.58	$0.54	$0.55	$0.53	$0.52	$0.50	$2.38	$2.10	$1.89

STOCKHOLDERS_EQUITY_AND_EARNIN4

STOCKHOLDERS' EQUITY AND EARNINGS PER SHARE (Details 3)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share
Excluded from the computation of diluted EPS (in shares)	20	177	340
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share
Excluded from the computation of diluted EPS (in shares)	7	10	5

STOCKHOLDERS_EQUITY_AND_EARNIN5

STOCKHOLDERS' EQUITY AND EARNINGS PER SHARE (Details 4) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement
Balance, beginning of the period	($30,459)	$4,669	($33,940)
Net unrealized gains (losses) arising during period	40,911	-27,833	42,899
Less: reclassification adjustment for losses included in net income	-6,215	-7,295	-452
Net unrealized gains (losses)	34,696	-35,128	42,447
Noncredit-related impairment loss on securities			-2,938
Foreign exchange translation adjustment			-900
Balance, end of the period	4,237	-30,459	4,669
Investment Securities Available-for-Sale
Statement
Balance, beginning of the period	-30,538	4,643	-34,848
Net unrealized gains (losses) arising during period	41,008	-28,169	42,868
Less: reclassification adjustment for losses included in net income	-6,294	-7,012	-439
Net unrealized gains (losses)	34,714	-35,181	42,429
Noncredit-related impairment loss on securities			-2,938
Balance, end of the period	4,176	-30,538	4,643
Other Investments
Statement
Balance, beginning of the period	79	26	8
Net unrealized gains (losses) arising during period	-97	336	31
Less: reclassification adjustment for losses included in net income	79	-283	-13
Net unrealized gains (losses)	-18	53	18
Balance, end of the period	61	79	26
Foreign Currency Translation Adjustment
Statement
Balance, beginning of the period				900
Foreign exchange translation adjustment			-900
Balance, end of the period			$0	$900

STOCKHOLDERS_EQUITY_AND_EARNIN6

STOCKHOLDERS' EQUITY AND EARNINGS PER SHARE (Details 5) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Unrealized gains (losses) on investment securities available-for-sale:
Net unrealized gains (losses) arising during period, before-tax amount	$70,704		($48,567)		$73,910
Less: reclassification adjustment for gains included in net income, before-tax amount	-10,851	[1]	-12,089	[1]	-757	[1]
Net unrealized gains (losses), before-tax amount	59,853		-60,656		73,153
Noncredit-related impairment loss on securities					-5,066
Foreign currency translation adjustments, before-tax amount					-1,552
Unrealized gains (losses) on other investment securities:
Net unrealized (losses) gains arising during period, before-tax amount	-167		579		53
Less: reclassification adjustment for (gains) losses included in income, before-tax amount	136	[2]	-488	[2]	-23	[2]
Net unrealized gains (losses), before-tax amount	-31		91		30
Other comprehensive income (loss), before-tax amount	59,822		-60,565		66,565
Unrealized gains (losses) on investment securities available-for-sale:
Net unrealized gains (losses) arising during period, tax expense or benefit	-29,696		20,398		-31,042
Less: reclassification adjustment for gains included in net income, tax expense or benefit	4,557	[1]	5,077	[1]	318	[1]
Net unrealized gains (losses), tax expense or benefit	-25,139		25,475		-30,724
Non credit-related impairment loss on securities, tax effect					2,128
Foreign currency translation adjustments, tax (expense) or benefit					652
Unrealized gains (losses) on other investment securities:
Net unrealized gains (losses) arising during period, tax expense or benefit	70		-243		-22
Less: reclassification adjustment for gains included in net income, tax expense or benefit	-57	[2]	205	[2]	10	[2]
Net unrealized gains (losses), tax expense or benefit	13		-38		-12
Other comprehensive income (loss), tax expense or benefit	-25,126		25,437		-27,956
Unrealized gains (losses) on investment securities available-for-sale:
Net unrealized gains (losses) arising during period, net-of-tax amount	41,008		-28,169		42,868
Less: reclassification adjustment for gains included in net income, net-of-tax amount	-6,294	[1]	-7,012	[1]	-439	[1]
Net unrealized gains (losses), net-of-tax amount	34,714		-35,181		42,429
Non credit-related impairment loss on securities, net of tax amount					-2,938
Foreign currency translation adjustments					-900
Unrealized gains (losses) on other investment securities
Net unrealized gains (losses) arising during period, net-of-tax amount	-97		336		31
Less: reclassification adjustment for gains included in net income, net-of-tax amount	79	[2]	-283	[2]	-13	[2]
Net unrealized gains (losses), net-of-tax amount	-18		53		18
Other comprehensive income (loss)	$34,696		($35,128)		$38,609
[1]	The pretax amount is reported in net gains on sales of investment securities in the consolidated statements of income.
[2]	The pretax income is reported in dividend and other investment income in the consolidated statements of income.

REGULATORY_REQUIREMENTS_Detail

REGULATORY REQUIREMENTS (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Actual
Total Capital (to Risk-Weighted Assets), Amount	$2,753,598,000	$2,395,109,000
Tier I Capital (to Risk-Weighted Assets), Amount	2,405,452,000	2,102,476,000
Tier I Capital (to Average Assets), Amount	2,405,452,000	2,102,476,000
Total Capital (to Risk-Weighted Assets), Ratio (as a percent)	12.60%	13.50%
Tier I Capital (to Risk-Weighted Assets), Ratio (as a percent)	11.00%	11.90%
Tier I Capital (to Average Assets), Ratio (as a percent)	8.40%	8.60%
For Capital Adequacy Purposes
Total Capital (to Risk-Weighted Assets), Amount	1,754,519,000	1,416,203,000
Tier I Capital (to Risk-Weighted Assets), Amount	877,259,000	708,102,000
Tier I Capital (to Average Assets), Amount	1,140,045,000	976,596,000
Total Capital (to Risk-Weighted Assets), Ratio (as a percent)	8.00%	8.00%
Tier I Capital (to Risk-Weighted Assets), Ratio (as a percent)	4.00%	4.00%
Tier I Capital (to Average Assets), Ratio (as a percent)	4.00%	4.00%
Regulatory Requirements - Additional Disclosure
Minimum total consolidated assets for exclusion of trust preferred securities as Tier I regulatory capital	15,000,000,000
Trust preferred securities as a percentage of the Company's Tier I capital	3.10%	4.40%
Minimum value of assets held by depository institutions and top-tier bank holding companies to be in compliance with the Basel III Capital Rules	500,000,000
East West Bank
Actual
Total Capital (to Risk-Weighted Assets), Amount	2,590,174,000	2,262,494,000
Tier I Capital (to Risk-Weighted Assets), Amount	2,316,615,000	2,041,894,000
Tier I Capital (to Average Assets), Amount	2,316,615,000	2,041,894,000
Total Capital (to Risk-Weighted Assets), Ratio (as a percent)	11.80%	12.90%
Tier I Capital (to Risk-Weighted Assets), Ratio (as a percent)	10.60%	11.60%
Tier I Capital (to Average Assets), Ratio (as a percent)	8.20%	8.40%
For Capital Adequacy Purposes
Total Capital (to Risk-Weighted Assets), Amount	1,750,006,000	1,407,944,000
Tier I Capital (to Risk-Weighted Assets), Amount	875,003,000	703,972,000
Tier I Capital (to Average Assets), Amount	1,136,734,000	973,958,000
Total Capital (to Risk-Weighted Assets), Ratio (as a percent)	8.00%	8.00%
Tier I Capital (to Risk-Weighted Assets), Ratio (as a percent)	4.00%	4.00%
Tier I Capital (to Average Assets), Ratio (as a percent)	4.00%	4.00%
To Be Well Capitalized Under Prompt Corrective Action Provisions
Total Capital (to Risk-Weighted Assets), Amount	2,187,508,000	1,759,931,000
Tier I Capital (to Risk-Weighted Assets), Amount	1,312,505,000	1,055,958,000
Tier I Capital (to Average Assets), Amount	1,420,917,000	1,217,448,000
Total Capital (to Risk-Weighted Assets), Ratio (as a percent)	10.00%	10.00%
Tier I Capital (to Risk-Weighted Assets), Ratio (as a percent)	6.00%	6.00%
Tier I Capital (to Average Assets), Ratio (as a percent)	5.00%	5.00%
Reserve Requirement
Daily average reserve requirement	$325,700,000	$218,500,000

SEGMENT_INFORMATION_Details

SEGMENT INFORMATION (Details)	12 Months Ended
	Dec. 31, 2014
	item
SEGMENT INFORMATION
Number of operating segments	3
Number of business divisions	3
Number of segment whom broad administrative support are provided	2

SEGMENT_INFORMATION_Details_2

SEGMENT INFORMATION (Details 2) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Segment Reporting Information
Interest income	$287,135	$285,948	$294,442	$286,173	$293,203	$281,706	$255,353	$238,423	$1,153,698		$1,068,685		$1,051,095
Charge for funds used									-283,384		-220,957		-160,092
Interest spread on funds used									870,314		847,728		891,003
Interest expense	-27,647	-28,974	-27,992	-28,207	-28,195	-27,456	-27,709	-29,132	-112,820		-112,492		-132,168
Credit on funds provided									283,384		220,957		160,092
Interest spread on funds provided									170,564		108,465		27,924
Net interest income (loss)	259,488	256,974	266,450	257,966	265,008	254,250	227,644	209,291	1,040,878		956,193		918,927
Provision for loan losses									49,158		22,364		65,184
Depreciation, amortization and accretion									114,121	[1]	97,110	[1]	43,751	[1]
Goodwill	469,433				337,438				469,433		337,438		337,438
Segment pre-tax profit	113,047	75,112	115,606	111,690	98,564	108,906	111,870	106,510	415,455		425,850		425,592
Segment assets	28,738,049				24,730,068				28,738,049		24,730,068		22,536,110
Retail Banking
Segment Reporting Information
Interest income									378,445		374,818		356,244
Charge for funds used									-94,162		-86,552		-85,811
Interest spread on funds used									284,283		288,266		270,433
Interest expense									-48,020		-47,287		-57,401
Credit on funds provided									225,873		173,194		130,713
Interest spread on funds provided									177,853		125,907		73,312
Net interest income (loss)									462,136		414,173		343,745
Provision for loan losses									14,979		10,911		28,729
Depreciation, amortization and accretion									14,376	[1]	19,865	[1]	12,869	[1]
Goodwill	357,207				320,566				357,207		320,566		320,566
Segment pre-tax profit									166,637		123,876		74,836
Segment assets	7,621,808				7,820,191				7,621,808		7,820,191		6,552,217
Commercial Banking
Segment Reporting Information
Interest income									715,075		627,118		617,041
Charge for funds used									-141,652		-116,161		-118,688
Interest spread on funds used									573,423		510,957		498,353
Interest expense									-15,650		-15,185		-23,226
Credit on funds provided									38,592		29,262		13,138
Interest spread on funds provided									22,942		14,077		-10,088
Net interest income (loss)									596,365		525,034		488,265
Provision for loan losses									34,179		11,453		36,455
Depreciation, amortization and accretion									-8,372	[1]	8,120	[1]	-13,277	[1]
Goodwill	112,226				16,872				112,226		16,872		16,872
Segment pre-tax profit									276,601		272,369		266,168
Segment assets	15,595,862				11,545,405				15,595,862		11,545,405		10,421,160
Other
Segment Reporting Information
Interest income									60,178		66,749		77,810
Charge for funds used									-47,570		-18,244		44,407
Interest spread on funds used									12,608		48,505		122,217
Interest expense									-49,150		-50,020		-51,541
Credit on funds provided									18,919		18,501		16,241
Interest spread on funds provided									-30,231		-31,519		-35,300
Net interest income (loss)									-17,623		16,986		86,917
Depreciation, amortization and accretion									108,117	[1]	69,125	[1]	44,159	[1]
Segment pre-tax profit									-27,783		29,605		84,588
Segment assets	$5,520,379				$5,364,472				$5,520,379		$5,364,472		$5,562,733
[1]	Includes amortization and accretion related to the FDIC indemnification asset.

PARENT_COMPANY_CONDENSED_FINAN2

PARENT COMPANY CONDENSED FINANCIAL STATEMENTS (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, except Share data, unless otherwise specified
ASSETS
Cash and cash equivalents	$1,039,885	$895,820	$1,323,106	$1,431,185
Investment securities available-for-sale	2,626,365	2,733,797
Other assets	1,001,770	784,907
TOTAL	28,738,049	24,730,068	22,536,110
LIABILITIES AND STOCKHOLDERS' EQUITY
Long-term debt	225,848	226,868
Total liabilities	25,887,481	22,365,843
STOCKHOLDERS' EQUITY
Common stock, $0.001 par value, 200,000,000 shares authorized; 163,772,218 and 163,098,008 shares issued in 2014 and 2013, respectively; 143,582,229 and 137,630,896 shares outstanding in 2014 and 2013, respectively.	164	163
Common stock, par value (in dollars per share)	$0.00	$0.00
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	163,772,218	163,098,008
Common stock, shares outstanding	143,582,229	137,630,896
Additional paid in capital	1,677,767	1,571,670
Retained earnings	1,598,598	1,360,130
Treasury stock, at cost-20,189,989 shares in 2014 and 25,467,112 shares in 2013	-430,198	-537,279
Treasury stock, shares	20,189,989	25,467,112
Accumulated other comprehensive income (loss), net of tax	4,237	-30,459	4,669	-33,940
Total stockholders' equity	2,850,568	2,364,225	2,382,122	2,311,743
TOTAL	28,738,049	24,730,068
Parent Company
ASSETS
Cash and cash equivalents	211,053	79,934	64,489	9,287
Investment securities available-for-sale	8,370	69,796
Investment in subsidiaries	2,841,684	2,400,937
Other investments	41,054	21,371
Other assets	22,474	37,037
TOTAL	3,124,635	2,609,075
LIABILITIES AND STOCKHOLDERS' EQUITY
Long-term debt	225,848	226,868
Other liabilities	48,219	17,982
Total liabilities	274,067	244,850
STOCKHOLDERS' EQUITY
Common stock, $0.001 par value, 200,000,000 shares authorized; 163,772,218 and 163,098,008 shares issued in 2014 and 2013, respectively; 143,582,229 and 137,630,896 shares outstanding in 2014 and 2013, respectively.	164	163
Common stock, par value (in dollars per share)	$0.00	$0.00
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	163,772,218	163,098,008
Common stock, shares outstanding	143,582,229	137,630,896
Additional paid in capital	1,677,767	1,571,670
Retained earnings	1,598,598	1,360,130
Treasury stock, at cost-20,189,989 shares in 2014 and 25,467,112 shares in 2013	-430,198	-537,279
Treasury stock, shares	20,189,989	25,467,112
Accumulated other comprehensive income (loss), net of tax	4,237	-30,459
Total stockholders' equity	2,850,568	2,364,225
TOTAL	$3,124,635	$2,609,075

PARENT_COMPANY_CONDENSED_FINAN3

PARENT COMPANY CONDENSED FINANCIAL STATEMENTS (Details 2) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of income
Interest expense	$27,647	$28,974	$27,992	$28,207	$28,195	$27,456	$27,709	$29,132	$112,820	$112,492	$132,168
Compensation and net occupancy reimbursement to subsidiary									63,815	56,641	55,475
Other expense									92,359	77,576	80,582
Income before income taxes and equity in undistributed income of subsidiaries	113,047	75,112	115,606	111,690	98,564	108,906	111,870	106,510	415,455	425,850	425,592
Income tax benefit	-20,049	13,644	-31,618	-34,949	-22,782	-35,749	-37,855	-34,419	-72,972	-130,805	-143,942
NET INCOME	92,998	88,756	83,988	76,741	75,782	73,157	74,015	72,091	342,483	295,045	281,650
Parent Company
Statement of income
Dividends from subsidiaries									111,701	319,085	324,094
Other income									7,414	821	2
Total income									119,115	319,906	324,096
Interest expense									4,823	3,436	3,092
Compensation and net occupancy reimbursement to subsidiary									4,039	3,662	2,573
Other expense									50,280	12,677	1,309
Total expense									59,142	19,775	6,974
Income before income taxes and equity in undistributed income of subsidiaries									59,973	300,131	317,122
Income tax benefit									80,674	22,885	2,892
Equity in undistributed income (loss) of subsidiaries									201,836	-27,971	-38,364
NET INCOME									$342,483	$295,045	$281,650

PARENT_COMPANY_CONDENSED_FINAN4

PARENT COMPANY CONDENSED FINANCIAL STATEMENTS (Details 3) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$92,998	$88,756	$83,988	$76,741	$75,782	$73,157	$74,015	$72,091	$342,483	$295,045	$281,650
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization									127,625	101,169	82,536
Stock compensation costs									13,883	13,548	12,668
Tax benefit from stock compensation plans, net									-6,513	-5,522	-462
Net cash provided by operating activities									392,898	425,845	287,526
Purchases of:
Investment securities available-for-sale									-960,135	-1,316,764	-1,835,823
Proceeds from sale of:
Investment securities available-for-sale									623,689	663,569	1,230,134
Net cash used in investing activities									-2,359,893	-2,734,846	-758,905
Payment for:
Repayment of long-term debt									-30,310	-10,310	-75,000
Repurchase of vested shares due to employee tax liability									-10,326	-13,833	-3,012
Repurchase of shares of treasury stock pursuant to the Stock Repurchase Plan										-199,992	-199,950
Proceeds from:
Issuance of common stock pursuant to various stock plans and agreements									6,794	3,054	3,821
Tax benefit from stock compensation plans, net									6,513	5,522	462
Net cash provided by financing activities									2,111,060	1,881,715	364,200
NET INCREASE IN CASH AND CASH EQUIVALENTS									144,065	-427,286	-108,079
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR				895,820				1,323,106	895,820	1,323,106	1,431,185
CASH AND CASH EQUIVALENTS, END OF YEAR	1,039,885				895,820				1,039,885	895,820	1,323,106
Cash paid during the year for:
Interest									112,695	112,169	136,760
Noncash investing and financing activities:
Conversion of preferred stock to common stock										83,027
Issuance of common stock related to acquisition									190,830
Parent Company
CASH FLOWS FROM OPERATING ACTIVITIES
Net income									342,483	295,045	281,650
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed (income) of subsidiaries									-314,225	-291,659	-285,636
Depreciation and amortization									46,365	8,806	445
Gains on sales of investment securities and other investments									-4,357	-161
Tax benefit from stock compensation plans, net									-6,513	-5,522	-462
Net change in other assets									186,232	293,153	322,361
Net change in other liabilities									150	-41	-25
Net cash provided by operating activities									250,135	299,621	318,333
Purchases of:
Investment securities available-for-sale									-9,000	-69,986
Equity investments									-53,071	-12,970	-234
Proceeds from sale of:
Investment securities available-for-sale									74,002
Net cash used in investing activities									11,931	-82,956	-234
Payment for:
Repayment of long-term debt									-30,310	-10,310
Repurchase of vested shares due to employee tax liability									-10,326	-13,833	-3,012
Cash dividends on preferred stock										-3,428	-6,857
Cash dividends on common stock									-103,618	-82,862	-57,361
Repurchase of shares of treasury stock pursuant to the Stock Repurchase Plan										-199,992	-199,950
Proceeds from:
Increase in long-term borrowings										100,000
Issuance of common stock pursuant to various stock plans and agreements									6,794	3,683	3,821
Tax benefit from stock compensation plans, net									6,513	5,522	462
Net cash provided by financing activities									-130,947	-201,220	-262,897
NET INCREASE IN CASH AND CASH EQUIVALENTS									131,119	15,445	55,202
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR				79,934				64,489	79,934	64,489	9,287
CASH AND CASH EQUIVALENTS, END OF YEAR	211,053				79,934				211,053	79,934	64,489
Cash paid during the year for:
Interest									4,462	3,292	3,112
Noncash investing and financing activities:
Conversion of preferred stock to common stock										83,027
Issuance of common stock related to acquisition									$190,830

QUARTERLY_FINANCIAL_INFORMATIO2

QUARTERLY FINANCIAL INFORMATION (unaudited) (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
QUARTERLY FINANCIAL INFORMATION (unaudited)
Interest and dividend income	$287,135	$285,948	$294,442	$286,173	$293,203	$281,706	$255,353	$238,423	$1,153,698	$1,068,685	$1,051,095
Interest expense	27,647	28,974	27,992	28,207	28,195	27,456	27,709	29,132	112,820	112,492	132,168
Net interest income	259,488	256,974	266,450	257,966	265,008	254,250	227,644	209,291	1,040,878	956,193	918,927
Provision for loan losses on non-covered loans	19,671	7,556	8,944	7,954	6,286	4,535	8,277	-762	44,125	18,336	60,168
(Reversal of) provision for loan losses on covered loans	-671	7,669	-944	-1,021	-820	-964	723	5,089	5,033	4,028	5,016
Net interest income after provision for loan losses	240,488	241,749	258,450	251,033	259,542	250,679	218,644	204,964	991,720	933,829	853,743
Noninterest (loss) income	7,805	10,342	-14,945	-14,916	-36,594	-41,421	-12,354	-2,099	-11,714	-92,468	-5,618
Noninterest expense	135,246	176,979	127,899	124,427	124,384	100,352	94,420	96,355	564,551	415,511	422,533
Income before provision of income taxes	113,047	75,112	115,606	111,690	98,564	108,906	111,870	106,510	415,455	425,850	425,592
Provision (benefit) for income taxes	20,049	-13,644	31,618	34,949	22,782	35,749	37,855	34,419	72,972	130,805	143,942
Net income	92,998	88,756	83,988	76,741	75,782	73,157	74,015	72,091	342,483	295,045	281,650
Preferred stock dividends							1,714	1,714		3,428	6,857
Net income available to common stockholders					$75,782	$73,157	$72,301	$70,377	$342,483	$291,617	$274,793
Basic earnings per share	$0.65	$0.62	$0.59	$0.54	$0.55	$0.53	$0.52	$0.51	$2.39	$2.11	$1.92
Diluted earnings per share	$0.65	$0.62	$0.58	$0.54	$0.55	$0.53	$0.52	$0.50	$2.38	$2.10	$1.89

SUBSEQUENT_EVENTS_Details

SUBSEQUENT EVENTS (Details) (Subsequent event, Dividend declared, Common Stock, USD $)	Jan. 21, 2015
Subsequent event | Dividend declared | Common Stock
Subsequent events
Dividend payable (in dollars per share)	$0.20