Pacwest Bancorp (PACW) 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	Feb. 09, 2015	Jun. 30, 2014
Document and Entity Information [Abstract]
Entity Registrant Name	PACWEST BANCORP
Entity Central Index Key	1102112
Document Period End Date	31-Dec-14
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Current Fiscal Year End Date	-19
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Amendment Flag	FALSE
Entity Common Stock, Shares Outstanding		101,913,512
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$4,308,404,322

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
ASSETS
Cash and due from banks	$164,757		$96,424
Interest-earning deposits in financial institutions	148,469		50,998
Total cash and cash equivalents	313,226		147,422
Securities available-for-sale, at fair value	1,567,177		1,494,745
Federal Home Loan Bank stock, at cost	40,609		27,939
Total investment securities	1,607,786		1,522,684
Gross loans and leases	11,904,684		4,313,335
Deferred fees and costs	22,252		983
Allowance for loan and lease losses	-84,455		-82,034
Total loans and leases, net	11,797,977		4,230,318
Equipment leased to others under operating leases	122,506		0
Premises and equipment, net	36,551		32,435
Foreclosed assets, net	43,721	[1]	55,891	[1]
Goodwill	1,720,479	[2]	208,743	[2]
Core deposit and customer relationship intangibles, net	17,204		17,248
FDIC loss sharing asset	18,734		45,524
Deferred tax asset, net	284,411		79,636
Other assets	272,205		193,462
Total assets	16,234,800		6,533,363
LIABILITIES:
Noninterest-bearing deposits	2,931,352		2,318,446
Interest-bearing deposits	8,823,776		2,962,541
Total deposits	11,755,128	[3]	5,280,987	[3]
Borrowings	383,402		113,726
Subordinated debentures	433,583		132,645
Accrued interest payable and other liabilities	156,262		196,912
Total liabilities	12,728,375		5,724,270
Commitments and contingencies	0		0
STOCKHOLDERS' EQUITY:
Preferred stock ($0.01 par value; 5,000,000 shares authorized; none issued and outstanding)	0		0
Common stock ($0.01 par value, 200,000,000 and 75,000,000 shares authorized at December 31, 2014 and 2013; 104,219,197 and 46,526,124 shares issued, respectively, includes 1,108,505 and 1,216,524 shares of unvested restricted stock, respectively)	1,042		465
Additional paid-in capital	3,807,167		1,286,737
Accumulated deficit	-285,517		-454,422
Treasury stock, at cost (1,197,180 and 703,290 shares at December 31, 2014 and 2013)	-42,647		-20,340
Accumulated other comprehensive income, net	26,380		-3,347
Total stockholders' equity	3,506,425		809,093
Total liabilities and stockholders' equity	$16,234,800		$6,533,363
[1]	(1)As of December 31, 2014 and 2013, the amounts of covered foreclosed assets were $9.3 million and $9.0 million.
[2]	(1)The increase in the goodwill for the Community Banking segment and National Lending segment during 2014 was due primarily to $1.5 billion from the CapitalSource merger.
[3]	(2)The negative balance for total deposits in the “Other” segment represents the elimination of holding company cash held in deposit accounts at the Bank.

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Preferred Stock, Shares Authorized	$0.01	$0.01
Preferred Stock, Value, Outstanding	5,000,000	5,000,000
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	200,000,000	75,000,000
Common Stock, Shares, Issued, Acquisitions	104,219,197	46,526,124
Equity Instruments Other than Options, Nonvested, Number	1,108,505	1,216,524
Common Stock, Shares Held in Employee Trust, Shares		1,216,524
Treasury Stock, Shares	1,197,180	703,290

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	3 Months Ended				12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Interest income:
Loans and leases	$83,856	$85,158	$71,631	$69,269	$657,097	$272,726	$260,230
Investment securities					47,345	36,923	35,657
Deposits in financial institutions					333	265	228
Total interest income					704,775	309,914	296,115
Interest expense:
Deposits					27,332	7,868	13,271
Borrowings					496	537	2,656
Subordinated debentures					14,570	3,796	3,721
Total interest expense	2,598	2,869	3,158	3,576	42,398	12,201	19,648
Net interest income	81,258	82,289	68,473	65,693	662,377	297,713	276,467
Provision (negative provision) for credit losses	-1,338	-4,167	-1,842	3,137	11,499	-4,210	-12,819
Net interest income after provision (negative provision) for credit losses					650,878	301,923	289,286
Noninterest income:
Service charges on deposit accounts					11,233	11,765	12,852
Other commissions and fees					18,602	8,416	8,126
Leased equipment income					16,669	0	0
Gain on sale of loans and leases					601	1,791	2,767
Gain on securities	-272	5,222	0	409	4,841	5,359	1,239
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net					0	0	-1,115
FDIC loss sharing expense, net	-10,593	-7,032	-5,410	-3,137	-31,730	-26,172	-10,070
Other income					21,971	3,085	2,073
Total noninterest income	-3,926	5,127	203	2,840	42,187	4,244	15,872
Noninterest expense:
Compensation and benefits					165,499	107,067	94,967
Occupancy					40,606	29,459	28,113
Data processing					14,618	9,494	9,120
Other professional services					11,234	6,754	5,903
Insurance and assessments					10,907	5,596	5,284
Intangible asset amortization	16,673	5,450	17,997	692	6,268	5,402	6,326
Leased equipment depreciation					9,159	0	0
Foreclosed assets expense (income), net	-569	-420	-14	-500	5,401	-1,503	10,931
Acquisition, integration and reorganization costs	49,984	51,170	46,233	43,991	101,016	40,812	4,089
Debt termination					0	0	22,598
Other expense					44,036	27,606	24,331
Total noninterest expense					408,744	230,687	211,662
Earnings from continuing operations before taxes	12,582	35,383	6,302	21,213	284,321	75,480	93,496
Income tax expense	-9,135	-11,243	-1,906	-7,719	-113,853	-30,003	-36,695
Net earnings from continuing operations					170,468	45,477	56,801
Loss from discontinued operations before taxes	-578	39	-81	0	-2,677	-620	0
Income tax benefit	240	-16	34	0	1,114	258	0
Net loss from discontinued operations	-338	23	-47	0	-1,563	-362	0
Net earnings	$3,109	$24,163	$4,349	$13,494	$168,905	$45,115	$56,801
Net earnings from continuing operations (usd per share)	$70	$530	$110	$370	$1.94	$1.09	$1.54
Basic income per share (usd per share)	$60	$530	$110	$370	$1.92	$1.08	$1.54
Net earnings from continuing operations (usd per share)	$70	$530	$110	$370	$1.94	$1.09	$1.54
Diluted income per share (usd per share)	$60	$530	$110	$370	$1.92	$1.08	$1.54
Dividends declared per share (usd per share)					$1.25	$1	$0.79

Consolidated_Statement_of_Comp

Consolidated Statement of Comprehensive Income (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net earnings	$168,905		$45,115		$56,801
Unrealized holding gains (losses) on securities available-for-sale	54,918		-57,136		17,532
Income tax (expense) benefit related to unrealized holding (losses) gains arising during the year	-22,317		26,190		-7,363
Unrealized holding gains (losses) on securities available-for-sale, net of tax	32,601		-30,946		10,169
Reclassification adjustment for gains included in net earnings (1)	-4,841	[1]	-5,359	[1]	-124	[1]
Income tax expense related to reclassification adjustment	1,967		58		52
Reclassification adjustment for gains included in net earnings, net of tax	-2,874		-5,301		-72
Other comprehensive income (loss), net of tax	29,727		-36,247		10,097
Comprehensive income	$198,632		$8,868		$66,898
[1]	For 2014 and 2013, entire amount recognized in "Gain on securities" on the Consolidated Statements of Earnings. For 2012, amount consists of: (1) $1.2 million recognized in "Gain on securities," offset by (2) $1.1 million recognized in "Other-than-temporary impairment loss on securities" on the Consolidated Statements of Earnings.

Consolidated_Statement_of_Comp1

Consolidated Statement of Comprehensive Income Statement of Comprehensive Income Footnote (Parenthetical) (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 Comprehensive Income [Abstract]
Gain on securities	$0	$0	$89	$4,752	($272)	$5,222	$0	$409	$4,841	$5,359	$1,239
Other than Temporary Impairment Losses, Investments, Portion in Other Comprehensive Loss, Tax, Portion Attributable to Parent									0	0	-1,115
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net									$0	$0	$1,115

Consolidated_Statement_of_Shar

Consolidated Statement of Shareholders' Equity (USD $)	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	First California Financial Group, Inc. [Member]	Capitalsource, Inc. [Member]
	USD ($)	USD ($)	USD ($)	USD ($)	USD ($)	USD ($)
Total stockholders' equity at Dec. 31, 2011	$546,203,000	$375,000	$1,084,691,000	($556,338,000)	($5,328,000)	$22,803,000
Shares, Outstanding at Dec. 31, 2011	37,254,318
Net Income	56,801,000			56,801,000
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	10,097,000	0	0	0	0	10,097,000
Stock Granted, Value, Share-based Compensation, Net of Forfeitures	5,999,000	2,000	5,997,000	0	0	0
Restricted stock surrendered	-1,475,000	0	0	0	-1,475,000	0
Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net	283,000	0	283,000	0	0	0
Dividends, Common Stock, Cash	-28,787,000	0	-28,787,000	0	0	0
Restricted Stock Surrendered	-63,681
Restricted Stock Award, Common Stock Net of Forfeitures	230,272
Total stockholders' equity at Dec. 31, 2012	589,121,000	377,000	1,062,184,000	-499,537,000	-6,803,000	32,900,000
Shares, Outstanding at Dec. 31, 2012	37,420,909
Net Income	45,115,000			45,115,000
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	-36,247,000	0	0	0	0	-36,247,000
Common stock issued due to acquisition	242,268,000	84,000	242,184,000	0	0	0
Stock Granted, Value, Share-based Compensation, Net of Forfeitures	21,246,000	4,000	21,242,000	0	0	0
Restricted stock surrendered	-13,537,000	0	0	0	-13,537,000	0
Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net	2,133,000	0	2,133,000	0	0	0
Dividends, Common Stock, Cash	-41,006,000	0	-41,006,000	0	0	0
Common Stock, Shares, Issued, Acquisitions	46,526,124						8,403,119
Restricted Stock Surrendered	-351,640
Restricted Stock Award, Common Stock Net of Forfeitures	350,446
Total stockholders' equity at Dec. 31, 2013	809,093,000	465,000	1,286,737,000	-454,422,000	-20,340,000	-3,347,000
Shares, Outstanding at Dec. 31, 2013	45,822,834
Net Income	168,905,000			168,905,000
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	29,727,000	0	0	0	0	29,727,000
Common stock issued due to acquisition	2,594,070,000	566,000	2,593,504,000	0	0	0
Stock Granted, Value, Share-based Compensation, Net of Forfeitures	36,474,000	11,000	36,463,000	0	0	0
Restricted stock surrendered	-22,307,000	0		0	-22,307,000	0
Stock Issued During Period, Value, Dividend Reinvestment Plan	115,000	0	115,000	0	0	0
Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net	4,625,000	0	4,625,000	0	0	0
Dividends, Common Stock, Cash	-114,277,000	0	-114,277,000	0	0	0
Common Stock, Shares, Issued, Acquisitions	104,219,197							56,601,997
Restricted Stock Surrendered	-493,890
Stock Issued During Period, Shares, Dividend Reinvestment Plan	2,583
Restricted Stock Award, Common Stock Net of Forfeitures	1,088,493
Total stockholders' equity at Dec. 31, 2014	$3,506,425,000	$1,042,000	$3,807,167,000	($285,517,000)	($42,647,000)	$26,380,000
Shares, Outstanding at Dec. 31, 2014	103,022,017

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 earnings	$168,905	$45,115	$56,801
Depreciation and amortization	39,153	31,509	25,792
Provision (negative provision) for credit losses	11,499	-4,210	-12,819
Gain on sale of foreclosed assets,net	-3,413	-5,201	-5,786
Provision for losses on foreclosed assets	7,307	2,515	14,333
Gain on sale of loans and leases, net	-601	-1,791	-2,767
(Gain) loss on sale of premises and equipment	-1,520	-21	155
Gain on branch sale	0	0	-297
Gain on securities, net	-4,841	-5,359	-1,239
Other than Temporary Impairment Losses, Investments, Portion in Other Comprehensive Loss, Tax, Portion Attributable to Parent	0	0	1,115
Unrealized gain on derivatives and foreign currencies, net	-3,487	0	0
Earned stock compensation	36,474	21,246	5,999
Write-off of goodwill relating to the asset financing segment reorganization	6,645	0	0
Tax effect included in stockholders' equity of restricted stock vesting	-4,625	-2,133	-283
Decrease (increase) in deferred income taxes, net	92,257	2,198	-3,737
Decrease (increase) in other assets	26,790	29,192	37,712
Decrease (increase) in other assets	22,708	-9,403	18,754
Decrease in accrued interest payable and other liabilities	-61,141	-53,405	-15,753
Net cash provided by operating activities	332,110	50,252	117,980
Cash flows from investing activities:
Cash acquired in acquisitions, net of cash consideration paid	346,047	273,013	-87,098
Net cash used in branch sale	0	0	-119,756
Net (increase) decrease in loans and leases	-782,424	275,740	232,549
Proceeds from sale of loans and leases	66,596	33,824	58,691
Proceeds from maturities and paydowns	123,949	306,536	415,854
Proceeds from sales	465,608	22,415	90,745
Purchases	-236,739	-550,211	-485,860
Collection of securities sales proceeds	484,084	0	0
Net redemptions of Federal Home Loan Bank stock	33,390	18,705	10,392
Proceeds from sales of foreclosed assets	24,464	36,490	59,614
Purchases of premises and equipment, net	-2,669	-3,604	-4,914
Proceeds from sales of premises and equipment	3,759	31	704
Net decrease of equipment leased to others under operating leases	30,493
Net cash provided by investing activities	556,558	412,939	170,921
Cash flows from financing activities:
Noninterest-bearing	506,533	18,068	271,934
Interest-bearing	-375,185	-547,081	-234,608
Net increase (decrease) in borrowings	269,741	101,250	-228,107
Restricted stock surrendered	-22,307	-13,537	-1,475
Redemption of subordinated debentures	0	0	-18,558
Repayment of acquired debt	-992,109	0	-180,796
Tax effect included in stockholders' equity of restricted vesting stock	4,625	2,133	283
Cash dividends paid, net	-114,162	-41,006	-28,787
Net cash used in financing activities	-722,864	-480,173	-420,114
Net increase (decrease) in cash and cash equivalents	165,804	-16,982	-131,213
Cash and cash equivalents, beginning of year	147,422	164,404	295,617
Cash and cash equivalents, end of year	313,226	147,422	164,404
Supplemental disclosures of cash flow information:
Cash paid for interest	34,788	13,275	21,614
Cash (received) paid for income taxes	-1,198	27,665	40,772
Loans transferred to foreclosed assets	9,806	15,416	40,207
Common stock issued in acquisitions	$2,594,070	$242,268	$0

Organization

Organization	12 Months Ended
	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations and Summary of Significant Accounting Policies	NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
	PacWest Bancorp is a bank holding company registered under the Bank Holding Company Act of 1956, as amended. Our principal business is to serve as the holding company for our Los Angeles‑based wholly-owned banking subsidiary, Pacific Western Bank, which we refer to as “Pacific Western” or the “Bank.” When we say “we,” “our,” or the “Company,” we mean PacWest Bancorp together with its subsidiaries on a consolidated basis. When we refer to “PacWest” or to the holding company, we are referring to PacWest Bancorp, the parent company, on a stand‑alone basis. As of December 31, 2014, we had total assets of $16.2 billion, gross loans and leases of 11.9 billion, total deposits of $11.8 billion and total stockholders' equity of $3.5 billion.
	Pacific Western is a full-service commercial bank offering a broad range of banking products and services including accepting demand, money market, and time deposits and originating loans and leases, including an array of commercial real estate loans and commercial lending products. The Bank has a foundation of locally generated and relationship-based deposits, with 80 full-service branches located primarily in Southern California, extending from San Diego County to California’s Central Coast, and we operate three banking offices in the San Francisco Bay area and four offices in the Central Valley. Our targeted collateral for our real estate loan offerings includes healthcare properties, office properties, industrial properties, multifamily properties, hospitality properties, and retail properties. Our commercial loan products include equipment loans and leases, asset-based loans, loans to finance companies, and loans secured by borrower future cash flows.
	As a result of the CapitalSource Inc. merger, Pacific Western Bank established the CapitalSource Division, which we also refer to as the National Lending segment. The CapitalSource Division lends throughout the United States, providing middle-market businesses asset-secured loans, equipment-secured loans, and cash flow loans and providing real estate investment firms real estate loans secured by various property types. Pacific Western’s leasing operation, Pacific Western Equipment Finance, and its group specializing in asset-based lending, CapitalSource Business Finance Group (formerly BFI Business Finance and First Community Financial), also became part of the CapitalSource Division. The CapitalSource Division’s loan and lease origination efforts are conducted through offices located in Chevy Chase, Maryland; Los Angeles and San Jose, California; St. Louis, Missouri; Denver, Colorado; Chicago, Illinois; New York, New York; and Midvale, Utah. When we refer to "CapitalSource Inc." we are referring to the company acquired on April 7, 2014 and when we refer to the "CapitalSource Division" we are referring to a division of Pacific Western Bank that specializes in middle-market lending on a nationwide basis.
	We generate our revenue primarily from interest received on loans and leases and, to a lesser extent, from interest received on investment securities, and fees received in connection with deposit services, extending credit and other services offered, including foreign exchange services. Our major operating expenses are the interest paid by the Bank on deposits and borrowings, compensation and general operating expenses.
	We have completed 27 acquisitions from May 2000 through December 31, 2014, including the acquisition of CapitalSource Inc. on April 7, 2014. Since 2000, our acquisitions have been accounted for using the acquisition method of accounting and, accordingly, the operating results of the acquired entities have been included in the consolidated financial statements from their respective acquisition dates. See Note 4, Acquisitions, for more information about the CapitalSource Inc. merger, the acquisition of First California Financial Group, Inc. ("FCAL") on May 31, 2013 and our 2012 acquisitions.
	(a) Basis of Presentation
	The accounting and reporting policies of the Company are in accordance with U.S. generally accepted accounting principles, which we may refer to as U.S. GAAP. All significant intercompany balances and transactions have been eliminated.
	(b) Use of Estimates
	Management of the Company has made a number of estimates and assumptions relating to the reporting of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reporting period to prepare these consolidated financial statements in conformity with U.S. GAAP. Actual results could differ from those estimates. Material estimates subject to change in the near term include, among other items, the allowance for credit losses, the carrying value of intangible assets, the carrying value of the FDIC loss sharing asset, and the realization of deferred tax assets.
	As described in Note 4, Acquisitions, below, we completed the merger with CapitalSource Inc. on April 7, 2014, the acquisition of FCAL on May 31, 2013 and three other acquisitions in 2012. The acquired assets and liabilities in each of these acquisitions were measured at their estimated fair values. Management made significant estimates and exercised significant judgment in estimating such fair values and accounting for the acquired assets and assumed liabilities in each of these transactions.
	(c) Reclassifications
	Certain prior period amounts have been reclassified to conform to the current period’s presentation format. On the balance sheet, the "Foreclosed assets, net" category includes other foreclosed assets which were previously reported within the "Other assets" category. On the statement of earnings, the "Other expense" category includes loan-related legal expenses which were previously reported within the "Other professional services" category. In the loan portfolio segment disclosure, the "Equipment finance" class of the "Commercial" loan portfolio segment includes the "Leases" loan portfolio which was previously reported as a separate loan portfolio segment. These reclassifications did not affect previously reported net income.
	(d) Cash and Cash Equivalents
	For purposes of the consolidated statements of cash flows, cash and cash equivalents consist of cash, due from banks, and interest‑earning deposits in financial institutions. Interest‑earning assets in financial institutions represent mostly cash held at the Federal Reserve Bank of San Francisco (“FRBSF”), the majority of which is immediately available.
	(e) Investment Securities
	We determine the classification of securities at the time of purchase. If we have the intent and the ability at the time of purchase to hold securities until maturity, they are classified as held‑to‑maturity. Investment securities held‑to‑maturity are stated at amortized cost. Securities to be held for indefinite periods of time, but not necessarily to be held‑to‑maturity or on a long‑term basis, are classified as available‑for‑sale and carried at estimated fair value, with unrealized gains or losses reported as a separate component of stockholders’ equity in accumulated other comprehensive income, net of applicable income taxes. Securities available‑for‑sale include securities that management intends to use as part of its asset/liability management strategy and that may be sold in response to changes in interest rates, prepayment risk, and other related factors. Securities are individually evaluated for appropriate classification when acquired; consequently, similar types of securities may be classified differently depending on factors existing at the time of purchase.
	The carrying values of all securities are adjusted for amortization of premiums and accretion of discounts over the period to maturity of the related security using the interest method. Realized gains or losses on the sale of securities, if any, are determined using the amortized cost of the specific securities sold. Declines in the fair value of debt securities classified as available-for-sale are reviewed to determine whether the impairment is other-than-temporary. This review considers a number of factors, including the severity of the decline in fair value, current market conditions, historical performance of the security, risk ratings and the length of time the security has been in an unrealized loss position. If we do not expect to recover the entire amortized cost basis of the security, then an other-than-temporary impairment is considered to have occurred. The cost basis of the security is written down to its fair value and the amount of the write‑down is recognized through a charge to earnings.
	Investments in Federal Home Loan Bank of San Francisco, or "FHLB," stock are carried at cost and evaluated regularly for impairment. FHLB stock is expected to be redeemed at par and is a required investment based on measurements of the Bank’s assets and/or borrowing levels.
	(f) Loans and Leases
	Originated loans. Loans are originated by the Company with the intent to hold them for investment and are stated at the principal amount outstanding, net of unearned income. Unearned income includes deferred unamortized nonrefundable loan fees and direct loan origination costs. Net deferred fees or costs are recognized as an adjustment to interest income over the contractual life of the loans using the effective interest method or taken into income when the related loans are paid off or sold. The amortization of loan fees or costs is discontinued when a loan is placed on nonaccrual status. Interest income is recorded on an accrual basis in accordance with the terms of the respective loan.
	Purchased loans. Purchased loans are stated at the principal amount outstanding, net of unearned discounts or unamortized premiums. All loans acquired in our acquisitions are initially measured and recorded at their fair value on the acquisition date. A component of the initial fair value measurement is an estimate of the credit losses over the life of the purchased loans. Purchased loans are also evaluated for impairment as of the acquisition date and are accounted for as “acquired non‑impaired” or “purchased credit impaired” loans.
	Acquired non‑impaired loans. Acquired non‑impaired loans are those loans for which there was no evidence of credit deterioration at their acquisition date and it was probable that we would be able to collect all contractually required payments. Acquired non‑impaired loans, together with originated loans, are referred to as non‑purchased credit impaired (“Non‑PCI”) loans. Purchase discount or premium on acquired non‑impaired loans is recognized as an adjustment to interest income over the contractual life of such loans using the effective interest method or taken into income when the related loans are paid off or sold.
	Purchased credit impaired loans. Purchased credit impaired (“PCI”) loans are accounted for in accordance with ASC Subtopic 310‑30, “Loans and Debt Securities Acquired with Deteriorated Credit Quality.” A purchased loan is deemed to be credit impaired when there is evidence of credit deterioration since its origination and it is probable at the acquisition date that we would be unable to collect all contractually required payments. We apply PCI loan accounting when we acquire loans deemed to be impaired, and as a general policy election when we acquire a portfolio of loans in a distressed bank acquisition.
	For PCI loans, at the time of acquisition we (i) calculated the contractual amount and timing of undiscounted principal and interest payments (the “undiscounted contractual cash flows”) and (ii) estimated the amount and timing of undiscounted expected principal and interest payments (the “undiscounted expected cash flows”). The difference between the undiscounted contractual cash flows and the undiscounted expected cash flows is the nonaccretable difference. The nonaccretable difference represents an estimate of the loss exposure of principal and interest related to the PCI loan portfolios; such amount is subject to change over time based on the performance of such loans. The carrying value of PCI loans is reduced by payments received, both principal and interest, and increased by the portion of the accretable yield recognized as interest income.
	The excess of the undiscounted expected cash flows at acquisition over the initial fair value of acquired impaired loans is referred to as the “accretable yield” and is recorded as interest income over the estimated life of the loans using the effective yield method if the timing and amount of the future cash flows is reasonably estimable. PCI loans that are contractually past due are still considered to be accruing and performing as long as there is an expectation that the estimated cash flows will be received. If the timing and amount of cash flows is uncertain, then cash payments received will be recognized as a reduction of the recorded investment.
	As part of the fair value process and the subsequent accounting, the Company aggregates PCI loans into pools having common credit risk characteristics such as type and risk rating. Increases in expected cash flows over those previously estimated increase the accretable yield and are recognized as interest income prospectively. Decreases in the amount and changes in the timing of expected cash flows compared to those previously estimated decrease the accretable yield and usually result in a provision for loan losses and the establishment of an allowance for loan losses. As the accretable yield increases or decreases from changes in cash flow expectations, the offset is a decrease or increase to the nonaccretable difference. The accretable yield is measured at each financial reporting date based on information then currently available and represents the difference between the remaining undiscounted expected cash flows and the current carrying value of the loans.
	Covered loans. We refer to loans that are covered by loss sharing agreements with the Federal Deposit Insurance Corporation (“FDIC”) as covered loans. Our covered loans include loans that we acquired in the Los Padres and Affinity acquisitions, and loans that we acquired in the FCAL acquisition where we assumed the loss sharing agreements between First California Bank (“FCB”) and the FDIC related to FCB’s acquisitions of Western Commercial Bank (“Western Commercial”) and San Luis Trust Bank (“San Luis”). We will be reimbursed for a substantial portion of any future losses on such loans under the terms of the FDIC loss sharing agreements. The FDIC loss sharing asset related to covered loans is reported separately in the balance sheet. See “-FDIC Loss Sharing Asset.”
	When we refer to non‑covered loans, we are referring to loans not covered by our loss sharing agreements with the FDIC.
	We apply PCI loan accounting to the majority of the covered loans as such covered loans were deemed to be impaired on the acquisition date. We apply acquired non‑impaired loan accounting to covered revolving credit agreements; mainly home equity loans and commercial asset‑based lines of credit, where the borrower has revolving privileges.
	Leases. We provide equipment financing to our customers through a variety of lease arrangements. The most common arrangement is a direct financing (capital) lease. For direct financing leases, lease receivables are recorded on the balance sheet but the leased property is not, although we generally retain legal title to the leased property until the end of each lease. Direct financing leases are stated at the net amount of minimum lease payments receivable, plus any unguaranteed residual value, less the amount of unearned income and net acquisition discount at the reporting date. Direct lease origination costs are amortized over the weighted average life of the lease portfolio. Leases acquired in an acquisition are initially measured and recorded at their fair value on the acquisition date. Purchase discount or premium on acquired leases is recognized as an adjustment to interest income over the contractual life of the leases using the effective interest method or taken into income when the related leases are paid off. Direct financing leases are subject to our allowance for loans and leases.
	Operating leases represents a line of business where we purchase equipment which is then leased to our customers. We receive periodic rental income payments, which are recorded as noninterest income, and the equipment remains on our balance sheet and is depreciated in line with our fixed asset accounting policy.
	Leases in process. We offer “progress funding” which works similarly to a bridge loan by financing an item to be leased during the construction or build phase. Lessees pay interest on the amount advanced to fund a project at an interest rate implicit in the master lease agreement; such income is deferred until the project funding is complete. The amount of funding advanced during the progress funding period is recorded in other assets. At the end of the progress funding period, we either (i) enter into a lease agreement with the lessee and the deferred income is accreted to interest income using an effective yield method over the life of the lease, or (ii) sell the lease to a third party lender and recognize the deferred income as part of any gain or loss on such sale.
	Loans and Leases Held for Sale. As part of our management of the loans and leases held in our portfolio, we will occasionally transfer loans from held for investment to held for sale. Upon transfer, any associated allowance for loan and lease loss is charged off and the carrying value of the loan is adjusted to the lower of cost or estimated fair value. Gains or losses on the sale of these loans are recorded in noninterest income.
	Delinquent or past due loans and leases. Loans and leases are considered delinquent when principal or interest payments are past due 30 days or more; delinquent loans may remain on accrual status between 30 days and 89 days past due.
	Nonaccrual loans and leases. Loans on which the accrual of interest has been discontinued are designated as nonaccrual loans. The accrual of interest on loans is discontinued when principal or interest payments are past due 90 days or when, in the opinion of management, there is a reasonable doubt as to collectability in the normal course of business. When loans are placed on nonaccrual status, all interest previously accrued but not collected is reversed against current period interest income. Income on nonaccrual loans is subsequently recognized only to the extent that cash is received and the loan’s principal balance is deemed collectable. Loans are restored to accrual status when the loans become both well‑secured and are in the process of collection. Leases are designated as nonaccrual leases when the recognition of interest has been discontinued. The recognition of interest on leases is discontinued when a lessee’s payments are past due 90 days or when, in the opinion of management, there is a reasonable doubt as to collectability. Interest on nonaccrual leases is subsequently recognized only to the extent that cash is received and the lease balance is deemed collectable. Leases are restored to accrual status when the leases become both well secured and are in the process of collection.
	Impaired loans and leases. A loan or lease is considered impaired when it is probable that we will be unable to collect all amounts due according to the contractual terms of the loan or lease agreement. Impaired loans and leases include loans and leases on nonaccrual status and performing restructured loans. Income from impaired loans is recognized on an accrual basis unless the loan is on nonaccrual status. Income from loans on nonaccrual status is recognized to the extent cash is received and when the loan’s principal balance is deemed collectable. We measure impairment of a loan by using the estimated fair value of the collateral, less estimated costs to sell, including senior obligations such as delinquent property taxes, if the loan is collateral‑dependent and the present value of the expected future cash flows discounted at the loan’s effective interest rate if the loan is not collateral‑dependent. The impairment amount on a collateral‑dependent loan is charged‑off to the allowance and the impairment amount on a loan that is not collateral‑dependent is set up as a specific reserve. We measure impairment of a lease based upon the present value of the scheduled lease and residual cash flows, discounted at the lease’s effective interest rate.
	Troubled debt restructurings. A loan is classified as a troubled debt restructuring when we grant a concession to a borrower experiencing financial difficulties. These concessions may include a reduction of the interest rate, principal or accrued interest, extension of the maturity date or other actions intended to minimize potential losses. All loan modifications are evaluated on an individual basis to determine whether such modifications meet the criteria to be classified as a troubled debt restructuring under ASC Subtopic 310‑40, “Troubled Debt Restructurings by Creditors.” Loans restructured at a rate equal to or greater than that of a new loan with comparable market risk at the time the loan is modified may be excluded from restructured loan disclosures in years subsequent to the restructuring if the loans are in compliance with their modified terms.
	A loan that has been placed on nonaccrual status that is subsequently restructured will usually remain on nonaccrual status until the borrower is able to demonstrate repayment performance in compliance with the restructured terms for a sustained period, typically for six months. A restructured loan may return to accrual status sooner based on other significant events or mitigating circumstances. A loan that has not been placed on nonaccrual status may be restructured and such loan may remain on accrual status after such restructuring. In these circumstances, the borrower has made payments before and after the restructuring. Generally, this restructuring involves a reduction in the loan interest rate and/or a change to interest‑only payments for a period of time. The restructured loan is considered impaired despite the accrual status and a specific reserve is calculated based on the present value of expected cash flows discounted at the loan’s original effective interest rate.
	(g) Allowances for Credit Losses
	Allowance for credit losses on Non‑PCI loans and leases. The allowance for credit losses on non-purchased credit impaired ("Non-PCI") loans and leases is the combination of the allowance for loan and lease losses and the reserve for unfunded loan commitments. The allowance for loan and lease losses is reported as a reduction of outstanding loan and lease balances and the reserve for unfunded loan commitments is included within "Accrued interest payable and other liabilities." The following discussion is for Non-PCI loans and leases and the allowance for credit losses thereon. Refer to "—Allowance for Credit Losses on Purchased Credit Impaired Loans" for the policy on purchased credit impaired loans. For loans and leases acquired and measured at fair value and deemed non-impaired on the acquisition date, our allowance methodology measures deterioration in credit quality or other inherent risks related to these acquired assets that arise after the acquisition date.
	The allowance for loan and lease losses is maintained at a level deemed appropriate by management to adequately provide for known and inherent risks in the loan and lease portfolio and other extensions of credit at the balance sheet date. The allowance is based upon our continual review of the credit quality of the loan and lease portfolio, which includes loan and lease payment trends, borrowers' compliance with loan agreements, borrowers' current and budgeted financial performance, collateral valuation trends, and current economic factors and external conditions that may affect our borrowers' ability to pay. Loans and leases that are deemed to be uncollectable are charged off and deducted from the allowance. The provision for loan and lease losses and recoveries on loans and leases previously charged off are added to the allowance.
	The allowance for loan and lease losses contains a general reserve component for loans and leases not considered impaired and a specific reserve component for loans and leases determined to be impaired.
	A loan or lease is considered impaired when it is probable that we will be unable to collect all amounts due according to the original contractual terms of the agreement. We assess our loans for impairment on an on-going basis using certain criteria such as payment performance, borrower reported financial results and budgets, and other external factors when appropriate. We measure impairment of a loan based upon the fair value of the loan’s collateral if the loan is collateral-dependent or the present value of cash flows, discounted at the loan’s effective interest rate, if the loan is not collateral-dependent. We measure impairment of a lease based upon the present value of the scheduled lease and residual cash flows, discounted at the lease's effective interest rate. To the extent a loan or lease exceeds the estimated collectable value, a specific reserve or charge-off is recorded depending upon the certainty of the estimate of loss. Smaller balance loans (under $250,000), with a few exceptions for certain loan types, are generally not individually assessed for impairment but are evaluated collectively.
	The methodology we use to estimate the general reserve component of our allowance for credit losses considers both objective and subjective criteria. The objective criteria uses our actual historical loan and lease charge-off experience on pools of similar loans and leases to establish loss factors that are applied to our current loan and lease balances to estimate inherent credit losses. The estimation of the allowance for credit losses at December 31, 2014 considered actual historical loan and lease charge-off experience over a five-year period starting with the fourth quarter of 2009. The five-year period is inclusive of the average timeframe over which charge-offs typically occur following loan or lease origination. The estimation of the allowance for credit losses at December 31, 2013 considered actual historical loan and lease charge-off experience over a four-year period starting with the fourth quarter of 2009. The increase in the historical look-back period from four years at December 31, 2013 to five years at December 31, 2014 allows the fourth quarter of 2009 and all of 2010 loan and lease charge-off experience to continue to be considered in the estimation of the allowance for credit losses. When estimating the general reserve component for the various pools of similar loan types, the loss factors applied to the loan pools consider the current credit risk ratings, giving greater weight to loans with more adverse credit risk ratings. We recognize that the determination of the allowance for loan and lease losses is sensitive to the assigned credit risk ratings and inherent loss rates at any given point in time. To ensure the accuracy of our credit risk ratings, an independent credit review function assesses the ratings assigned to loans on an on-going basis.
	The subjective criteria considered when establishing the loss factors include the following:
	•	current economic trends and forecasts;
	•	current commercial real estate values, performance trends, and overall outlook in the markets where we lend;
	•	legal and regulatory matters that could impact our borrowers’ ability to repay our loans;
	•	our loan portfolio composition and any loan concentrations;
	•	our current lending policies and the effects of any new policies or policy amendments;
	•	our new loan origination volume and the nature of it;
	•	our loan portfolio credit performance trends; and
	•	the results of our on-going independent credit review.
	The reserve for unfunded commitments is estimated using the same loss factors as used for the allowance for loan and lease losses and is computed based only on the expected usage of the unfunded commitments.
	The credit risk ratings assigned to every loan and lease are either “pass,” “special mention,” “substandard” or “doubtful” and defined as follows:
	•	Pass: Loans and leases classified as "pass" are not adversely classified and collection and repayment in full is expected.
	•	Special Mention: Loans and leases classified as "special mention" have a potential weakness that requires management's attention. If not addressed, these potential weaknesses may result in further deterioration in the borrower's ability to repay the loan or lease.
	•	Substandard: Loans and leases classified as "substandard" have a well-defined weakness or weaknesses that jeopardize the collection of the debt. They are characterized by the possibility that we will sustain some loss if the weaknesses are not corrected.
	•	Doubtful: Loans and leases classified as "doubtful" have all the weaknesses of those classified as "substandard," with the additional trait that the weaknesses make collection or repayment in full highly questionable and improbable.
	In addition, we may refer to the loans and leases classified as "substandard" and "doubtful" together as "classified" loans and leases. For further information on classified loans and leases, see Note 7, Loans and Leases.
	Management believes that the allowance for credit losses is appropriate for the known and inherent risks in our Non-PCI loan and lease portfolio and that the credit risk ratings and inherent loss rates currently assigned are appropriate. It is possible that others, given the same information, may at any point in time reach different conclusions that could result in a significant impact to the Company's financial statements. In addition, current credit risk ratings are subject to change as we continue to monitor our loans and leases. To the extent we experience, for example, increased levels of documentation deficiencies, adverse changes in collateral values, or negative changes in economic and business conditions that adversely affect our borrowers, our classified and impaired loans and leases may increase. Higher levels of classified and impaired loans and leases generally result in increased provisions for credit losses and an increased allowances for credit losses. Although we have established an allowance for credit losses that we consider appropriate, there can be no assurance that the established allowance will be sufficient to absorb related losses in the future.
	Our federal and state banking regulators, as an integral part of their examination process, periodically review the Company’s allowance for credit losses. Our regulators may require the Company to recognize additions to the allowance based on their judgments related to information available to them at the time of their examinations.
	Allowance for credit losses on PCI loans. The PCI loans are subject to our internal and external credit review. If deterioration in the expected cash flows results in a reserve requirement, a provision for credit losses is charged to earnings. For PCI loans, the allowance for loan losses is measured at the end of each financial reporting period based on expected cash flows. Decreases or (increases) in the amount and changes in the timing of expected cash flows on the PCI loans as of the financial reporting date compared to those previously estimated are usually recognized by recording a provision or a (negative provision) for credit losses on such loans.
(h) FDIC Loss Sharing Asset
The FDIC loss sharing asset relates to assets covered by the loss sharing agreements between the Bank and the FDIC arising from the acquisitions of Affinity Bank and Los Padres Bank and, through the FCAL acquisition, the assumption of the loss sharing agreements between First California Bank and the FDIC arising from FCB’s acquisition of Western Commercial and San Luis. The FDIC loss sharing assets related to Western Commercial and San Luis were measured at their fair value as of May 31, 2013 in conjunction with the FCAL acquisition. The FDIC loss sharing assets related to Los Padres and Affinity were measured at their estimated fair value at their respective acquisition dates.
An increase in the expected amount of losses on the covered assets will increase the FDIC loss sharing asset; such increase is recognized through a credit to FDIC loss sharing income. Recoveries on previous losses paid to us by the FDIC reduce the FDIC loss sharing asset by a charge to FDIC loss sharing income. In addition, decreases in the expected amount of losses on covered assets will decrease the amount of funds expected to be collected from the FDIC and will therefore reduce the FDIC loss sharing asset through higher prospective amortization expense. The FDIC loss sharing asset is being amortized to its estimated value over the lesser of the term of the loss sharing agreements or the remaining contractual life of the assets covered by the loss sharing agreements.
Both the Western Commercial and San Luis loss sharing agreements contain true‑up provisions, under which we will owe the FDIC amounts at the end of the loss sharing agreements based on the performance of the covered assets. The true‑up liability is included in other liabilities in the accompanying consolidated balance sheets.
Under the terms of the Affinity loss sharing agreement, the FDIC will (a) absorb 80% of losses and receive 80% of loss recoveries on the first $234 million of losses on covered assets and (b) absorb 95% of losses and receive 95% of loss recoveries on losses exceeding $234 million. The Affinity loss sharing provisions expired in the third quarter of 2014 for non single-family assets and will expire in the third quarter of 2019 for single family covered assets, while the related loss recovery provisions expire in the third quarters of 2017 and 2019, respectively.
Under the terms of the Los Padres loss sharing agreement, the FDIC will absorb 80% of losses and receive 80% of loss recoveries on the covered assets. The Los Padres loss sharing provisions expire in the third quarters of 2015 and 2020 for non‑single family and single family covered assets, respectively, while the related loss recovery provisions expire in the third quarters of 2018 and 2020, respectively.
Under the terms of the Western Commercial loss sharing agreement, the FDIC will absorb 80% of losses and receive 80% of loss recoveries on the covered assets; all of which were deemed to be non‑single family. The Western Commercial loss sharing provision expires in the fourth quarter of 2015, while the related loss recovery provision expires in the fourth quarter of 2018.
Under the terms of the San Luis loss sharing agreement, the FDIC will absorb 80% of losses and receive 80% of loss recoveries on the covered assets. The San Luis loss sharing provisions expire in the first quarters of 2016 and 2021 for non‑single family and single family covered assets, respectively, while the related loss recovery provisions expire in the first quarters of 2019 and 2021, respectively.
(i) Land, Premises and Equipment
Premises and equipment are stated at cost less accumulated depreciation and amortization. Land is not depreciated. Depreciation and amortization is charged to noninterest expense using the straight‑line method over the estimated useful lives of the assets. The estimated useful lives of furniture, fixtures and equipment range from 3 to 7 years and for buildings up to 35 years. Leasehold improvements are amortized over their estimated useful lives, or the life of the lease, whichever is shorter.
(j) Foreclosed Assets
Non‑covered Foreclosed Assets. Foreclosed assets includes other real estate owned, or OREO, and repossessed non-real estate assets. Foreclosed assets are initially recorded at the estimated fair value of the property, based on current independent appraisals obtained at the time of acquisition, less estimated costs to sell, including senior obligations such as delinquent property taxes. The excess of the recorded loan balance over the estimated fair value of the property at the time of acquisition less estimated costs to sell is charged to the allowance for loan losses. Any subsequent write‑downs are charged to noninterest expense and recognized through a foreclosed assets valuation allowance. Subsequent increases in the fair value of the asset less selling costs reduce the foreclosed assets valuation allowance, but not below zero, and are credited to noninterest expense. Gains and losses on the sale of foreclosed assets and operating expenses of such assets are also included in noninterest expense.
Covered OREO. Covered OREO are initially recorded at its estimated fair value on the acquisition date based on independent appraisals less estimated selling costs. Any subsequent write‑downs due to declines in fair value are charged to noninterest expense, and any recoveries of previous write-downs are credited to noninterest expense, without regard to the FDIC indemnification. The portion of the loss reimbursement or recovery due from or to the FDIC is recognized as FDIC loss sharing income or expense.
(k) Income Taxes
Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in earnings in the period that includes the enactment date. Any interest or penalties assessed by the taxing authorities is classified in the financial statements as income tax expense. Deferred tax assets and liabilities, net of valuation allowances, are grouped together and reported net on the consolidated balance sheets.
On a quarterly basis, the Company evaluates its deferred tax assets to assess whether they are expected to be realized in the future. This determination is based on currently available facts and circumstances, including our current and projected future tax positions, the historical level of our taxable income, and estimates of our future taxable income. In most cases, the realization of deferred tax assets is based on our future profitability. To the extent our deferred tax assets are no longer considered more likely than not to be realized, we could be required to record a valuation allowance on our deferred tax assets by charging earnings. The Company also evaluates existing valuation allowances periodically to determine if sufficient evidence exists to support an increase or reduction in the allowance.
(l) Goodwill and Other Intangible Assets
Goodwill arises from the acquisition method of accounting for business combinations and represents the excess of the purchase price over the fair value of the net assets and other identifiable intangible assets acquired. Goodwill and other intangible assets deemed to have indefinite lives generated from purchase business combinations are not subject to amortization and are instead tested for impairment no less than annually. Impairment exists when the carrying value of the goodwill exceeds its implied fair value. An impairment loss would be recognized in an amount equal to that excess as a charge to noninterest expense in the consolidated statement of earnings.
Intangible assets with estimable useful lives are amortized over such useful lives to their estimated residual values and reviewed for impairment at least quarterly. Core deposit intangible assets, which we refer to as CDI, and customer relationship intangible assets, which we refer to as CRI, are recognized apart from goodwill at the time of acquisition based on market valuations prepared by independent third parties. In preparing such valuations, the third parties consider variables such as deposit servicing costs, attrition rates, and market discount rates. CDI assets are amortized to expense over their useful lives, which we have estimated to range from 7 to 10 years. CRI assets are amortized to expense over their useful lives, which we have estimated to range from 4 to 5 years. The amortization expense represents the estimated decline in the value of the underlying deposits or customer relationships acquired. Both CDI and CRI are reviewed for impairment quarterly or earlier if events or changes in circumstances indicate that their carrying values may not be recoverable. If the recoverable amount of either CDI or CRI is determined to be less than its carrying value, we would then measure the amount of impairment based on an estimate of the intangible asset’s fair value at that time. If the fair value is below the carrying value, then the intangible asset is reduced to such fair value; an impairment loss for such amount would be recognized as a charge to noninterest expense in the consolidated statement of earnings.
(m) Stock‑Based Compensation
Compensation expense related to awards of time-based restricted stock is based on the fair value of the underlying stock on the award date and is recognized over the vesting period using the straight‑line method. The vesting of performance‑based restricted stock awards and recognition of related compensation expense may occur over a shorter vesting period if financial performance targets are achieved earlier than anticipated. Amortization of unvested performance‑based restricted stock is suspended when it becomes less than probable that the performance targets will be met. Amortization of unvested performance‑based restricted stock is discontinued and previous amortization amounts are credited to earnings when it becomes improbable that performance targets will be met. When and if it becomes probable in the future that the performance target will be met a catch up adjustment is made and amortization resumes.
Unvested restricted stock participates with common stock in any dividends declared and paid. Dividends paid on unvested restricted stock awards expected to vest and the related tax benefits are included as a net reduction to stockholders’ equity. Dividends paid on unvested restricted stock not expected to vest are charged to compensation expense.
(n) Business Segments
We present financial and descriptive information about our reportable operating segments including a measure of segment profit or loss, certain specific revenue and expense items and segment assets. We designate components of our business as reportable operating segments if the component a) engages in business activities from which it may earn revenues and incur expenses, b) has operating results that are regularly reviewed by executive management to make business decisions about resources to be allocated to the segment and assess its performance and c) has available discrete financial information. We currently operate as three reportable segments. The Company’s reportable segments consist of “Community Banking," “National Lending,” and “Other.”
(o) Derivative Instruments
Our derivative contracts primarily manage the foreign currency risk associated with certain assets. As of December 31, 2014, all of our derivatives were held for risk management purposes, and none were designated as accounting hedges. The objective is to manage the uncertainty of future foreign exchange rate fluctuations. These forward exchange contracts provide for a fixed exchange rate which has the effect of reducing or eliminating changes to anticipated cash flows to be received from foreign currency-denominated loan transactions as the result of changes to exchange rates. Our derivatives are recorded in other assets or other liabilities, as appropriate. The changes in fair value of our derivatives and the related interest are recognized in other income. At December 31, 2014, our derivative contracts had a notional value of $67.8 million.
Derivative instruments expose us to credit risk in the event of nonperformance by counterparties to such agreements. This risk exposure consists primarily of the termination value of agreements where we are in a favorable position. We manage the credit risk associated with various derivative agreements through counterparty credit review and monitoring procedures.
(p) Investments That Do Not Have Readily Determinable Fair Values
Investments in common or preferred stock that are not publicly traded and/or do not have a readily determinable fair value are accounted for pursuant to the equity method of accounting if we have the ability to significantly influence the operating and financial policies of an investee. This is generally presumed to exist when we own between 20% and 50% of a corporation, or when we own greater than 5% of a limited partnership or similarly structured entity. Our investment carrying values are included in other assets and our share of earnings and losses in equity method investees is included in other income. If we do not have significant influence over the investee, the cost method is used to account for the equity interest.
For investments accounted for using the cost or equity method of accounting, management evaluates information such as budgets, business plans, and financial statements of the investee in addition to quoted market prices, if any, in determining whether an other-than-temporary decline in value exists. Factors indicative of an other-than-temporary decline in value include, but are not limited to, recurring operating losses and credit defaults. We compare the estimated fair value of each investment to its carrying value quarterly. For any of our investments in which the estimated fair value is less than its carrying value, we consider whether the impairment of that investment is other-than-temporary. If we determine that an investment has sustained an other-than-temporary decline in its value, the equity interest is written down to its estimated fair value through other income and a new carrying value for the investment is established.
Realized gains or losses resulting from the sale of investments are calculated using the specific identification method and are included in other income.
(q) Comprehensive Income
Comprehensive income consists of net earnings and net unrealized gains (losses) on securities available‑for‑sale, net, and is presented in the consolidated statements of comprehensive income.
(r) Earnings Per Share
In accordance with ASC Topic 260, “Earnings Per Share,” all outstanding unvested share‑based payment awards that contain rights to nonforfeitable dividends are considered participating securities and are included in the two‑class method of determining basic and diluted earnings per share. All of our unvested restricted stock participates with our common stockholders in dividends. Accordingly, earnings allocated to unvested restricted stock are deducted from net earnings to determine that amount of earnings available to common stockholders. In the two‑class method, the amount of our earnings available to common stockholders is divided by the weighted average shares outstanding, excluding any unvested restricted stock, for both the basic and diluted earnings per share.
(s) Business Combinations
Business combinations completed after January 1, 2009, are accounted for under the acquisition method of accounting in accordance with ASC Topic 805, “Business Combinations.” Under the acquisition method, the acquiring entity in a business combination recognizes 100 percent of the acquired assets and assumed liabilities, regardless of the percentage owned, at their estimated fair values as of the date of acquisition. Any excess of the purchase price over the fair value of net assets and other identifiable intangible assets acquired is recorded as goodwill. To the extent the fair value of net assets acquired, including other identifiable assets, exceeds the purchase price, a bargain purchase gain is recognized. Assets acquired and liabilities assumed from contingencies must also be recognized at fair value, if the fair value can be determined during the measurement period. Results of operations of an acquired business are included in the statement of earnings from the date of acquisition. Acquisition‑related costs, including conversion and restructuring charges, are expensed as incurred.
(t) Recently Issued Accounting Standards
In January 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014‑01, “Investments-Equity Method and Joint Ventures (Topic 323): Accounting for Investments in Qualified Affordable Housing Projects.” ASU 2014‑01 allows investors in low‑income housing tax credit (“LIHTC”) entities that meet certain conditions to present the net tax benefits (net of the amortization of the cost of the investment) within income tax expense. The cost of the investments that meet the conditions will be amortized in proportion to (and over the same period as) the total expected tax benefits, including tax credits and other tax benefits, as they are realized on the tax return. ASU 2014‑01 is effective for us on January 1, 2015 and is to be applied retrospectively if investors elect the proportional amortization method. However, if investors have LIHTC investments accounted for under the effective yield method at adoption, they may continue to apply that method for those existing investments. The adoption of this standard permits expenses currently reported in noninterest expense to be reported in income tax expense. Early adoption was permitted. We adopted this standard effective January 1, 2015, elected the proportional amortization method, and it is not expected to have a material impact on our financial statements; however, total noninterest expense and income tax expense will change.
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 a creditor should reclassify mortgage loans collateralized by residential real estate from loans receivable to other real estate owned. ASU 2014‑04 defines when an in‑substance repossession or foreclosure has occurred and when a creditor is considered to have received physical possession of residential real estate collateralizing a mortgage loan. ASU 2014‑04 was effective for us on January 1, 2015 and can be applied either prospectively or using a modified retrospective transition method, and early adoption was permitted. The adoption of this standard in January 2015 will not have a material impact on our financial statements.
In April 2014, the FASB issued ASU 2014-08, "Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity." ASU 2014-08 is an amendment to Subtopic 205-20 that changes the criteria for reporting discontinued operations by raising the threshold for disposals to qualify as discontinued operations. This update aims to reduce the unnecessarily frequent reporting of disposals of small groups of assets that are recurring in nature. The revised definition states that a disposal of a component of an entity or a group of components of an entity is required to be reported in discontinued operations if the disposal represents a strategic shift that has (or will have) a major effect on an entity’s operations and financial results. ASU 2014-08 is effective for us for all disposals that occur after December 31, 2014. The adoption of this standard is not expected to have a material impact on our financial statements.
ASU 2014-09, "Revenue Recognition (Topic 606): Revenue from Contracts with Customers," was issued May 2014 and will be effective for annual and interim periods beginning after December 15, 2016. Early application is not permitted. ASU 2014-09 requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. ASU 2014-09 will replace most existing revenue recognition guidance in GAAP when it becomes effective. The standard permits the use of either the retrospective or cumulative effect transition method. The Company is evaluating the effect that ASU 2014-09 will have on its financial statements and related disclosures. The Company has not yet selected a transition method nor has it determined the effect of the standard on its ongoing financial reporting.
ASU 2014-12, "Compensation-Stock Compensation (Topic 718): Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period," was issued June 2014 and will be effective for annual and interim periods beginning after December 15, 2015. ASU 2014-12 applies to all reporting entities that grant their employees share-based payments in which the terms of the award provide for a performance target that affects vesting could be achieved after the requisite service period. That is the case when an employee is eligible to retire or otherwise terminate employment before the end of the period in which a performance target (for example, an initial public offering or a profitability target) could be achieved and still be eligible to vest in the award if and when the performance target is achieved. We do not currently have outstanding performance-based awards and, as a result, ASU 2014-12 would not impact our financial statements and its related disclosures.
In August 2014, the FASB issued ASU 2014-14, "Receivables - Troubled Debt Restructuring by Creditors (Subtopic 310-40): Classification of Certain Government-Guaranteed Mortgage Loans Upon Foreclosure." This ASU requires that a mortgage loan be derecognized and that a separate other receivable be recognized upon foreclosure if the following conditions are met: (1) the loan has a government guarantee that is not separable from the loan before foreclosure; (2) at the time of foreclosure, the creditor has the intent to convey the real estate property to the guarantor and make a claim on the guarantee, and the creditor has the ability to recover under that claim; and (3) at the time of foreclosure, any amount of the claim that is determined on the basis of the fair value of the real estate is fixed. Upon foreclosure, the separate other receivable should be measured based on the amount of the loan balance (principal and interest) expected to be recovered from the guarantor. ASU 2014-14 is effective for public business entities for reporting periods, including interim periods, beginning after December 15, 2014. The Company does not expect the effect of ASU 2014-14 to have a material impact on its financial statements and related disclosures.

Discontinued_Operations

Discontinued Operations	12 Months Ended
	Dec. 31, 2014
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	DISCONTINUED OPERATIONS
	Discontinued operations include the income and expense related to Electronic Payment Services ("EPS"), a discontinued division of the Bank acquired in connection with the FCAL acquisition. For the year ended December 31, 2014, the EPS division recorded no revenues and a pre-tax loss of $2.7 million. For the period from acquisition date to December 31, 2013, revenues and pre‑tax loss for the EPS division were $2.6 million and $620,000. Liabilities of the EPS division, which were $21.3 million and $123.0 million at December 31, 2014 and 2013, consist primarily of noninterest‑bearing deposits and are included in the consolidated balance sheets under the caption “Accrued interest payable and other liabilities.” For segment reporting purposes, the EPS division is included in our Community Banking segment.

Restricted_Cash_Balances

Restricted Cash Balances	12 Months Ended
	Dec. 31, 2014
Restricted Cash Balances [Abstract]
Restricted Cash Balances	RESTRICTED CASH BALANCES
	The Company is required to maintain reserve balances with the FRBSF. Such reserve requirements are based on a percentage of deposit liabilities and may be satisfied by cash on hand. The average reserves required to be held at the FRBSF for the years ended December 31, 2014 and 2013 were $10.0 million and $13.1 million.

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2014
Business Combinations [Abstract]
Acquisitions	ACQUISITIONS
	The following assets acquired and liabilities assumed of the acquired entities are presented at estimated fair value as of their respective acquisition dates:
		Acquisition and Date Acquired
		CapitalSource Inc.		First California Financial Group		American Perspective Bank		Celtic Capital Corporation		Pacific Western Equipment Finance
		7-Apr-14		31-May-13		1-Aug-12		3-Apr-12		3-Jan-12
		(In thousands)
	Assets Acquired:
	Cash and due from banks	$	768,553	$	6,124	$	3,370	$	3,435	$	7,092
	Interest‑earning deposits in financial institutions	60,612		266,889		10,081		—		—
	Investment securities available‑for‑sale	382,797		4,444		48,887		—		—
	FHLB stock	46,060		9,518		1,412		—		—
	Loans and leases	6,877,427		1,049,613		197,279		54,963		140,959
	Equipment leased to others under operating leases	160,015		—		—		—		—
	Premises and equipment	12,663		15,322		—		—		—
	Foreclosed assets	6,382		13,772		1,561		—		—
	FDIC loss sharing asset	—		17,241		—		—		—
	Income tax assets	312,757		33,360		2,194		19		—
	Goodwill	1,518,381		129,070		15,047		6,645		19,033
	Core deposit and customer relationship intangibles	6,720		7,927		1,924		1,300		1,700
	Leases in process	—		—		—		—		19,162
	Other assets(1)	582,985		27,576		2,040		720		1,887
	Total assets acquired	$	10,735,352	$	1,580,856	$	283,795	$	67,082	$	189,833
	Liabilities Assumed:
	Noninterest‑bearing deposits	$	4,631	$	361,166	$	40,673	$	—	$	—
	Interest‑bearing deposits	6,236,419		739,713		178,891		—		—
	Other borrowings	992,109		—		5,315		46,804		15,839
	Borrowings from parent	—		—		—		—		128,677
	Subordinated debentures	300,918		24,061		—		—		—
	Discontinued operations	—		184,619		—		—		—
	Accrued interest payable and other liabilities	124,087		19,729		840		2,278		10,317
	Total liabilities assumed	$	7,658,164	$	1,329,288	$	225,719	$	49,082	$	154,833
	Total consideration paid	$	3,077,188	$	251,568	$	58,076	$	18,000	$	35,000
	Summary of consideration:
	Cash paid	$	483,118	$	—	$	58,076	$	18,000	$	35,000
	PacWest common stock issued	2,594,070		242,268		—		—		—
	Cancellation of FCAL common stock owned by PacWest (at acquisition date fair value)	—		9,300		—		—		—
	Total	$	3,077,188	$	251,568	$	58,076	$	18,000	$	35,000
	___________________
	-1	The CapitalSouce, Inc. amount includes a $484 million receivable for securities sales proceeds.
	CapitalSource Inc. Merger
	We acquired CapitalSource Inc. on April 7, 2014. As part of the merger, CapitalSource Bank (“CSB”), a wholly-owned subsidiary of CapitalSource Inc., merged with and into Pacific Western Bank. We completed the merger in order to increase our loan and lease generation capabilities and to diversify our loan portfolio.
	Upon closing, we created the CapitalSource Division of the Bank. The CapitalSource Division lends throughout the United States, providing middle-market businesses asset-secured loans, equipment-secured loans and leases, and cash flow loans and providing real estate investment firms real estate loans secured by various property types. When we refer to "CapitalSource Inc." we are referring to the company acquired on April 7, 2014 and when we refer to the "CapitalSource Division" we are referring to a division of the Bank that provides on a nationwide basis senior secured real estate loans, equipment loans and leases, asset-based loans, loans to finance companies, and cash flow loans secured by the enterprise value of the borrowing entity.
	In the merger with CapitalSource Inc., each share of CapitalSource Inc. common stock was converted into the right to receive $2.47 in cash and 0.2837 of a share of PacWest common stock. PacWest issued an aggregate of approximately 56.6 million  shares of PacWest common stock to CapitalSource Inc. stockholders. Based on the closing price of PacWest’s common stock on April 7, 2014 of $45.83 per share, the aggregate consideration paid to CapitalSource Inc. common stockholders and holders of equity awards to acquire CapitalSource Inc. common stock was approximately $3.1 billion.
	CSB was a commercial lender which operated under a California Industrial Loan Bank charter headquartered in Los Angeles, California. CSB provided financial products to small to middle-market businesses nationwide and also provided certain depository products and services excluding demand deposit accounts to consumers in Southern and Central California. CSB’s loan origination efforts were conducted nationwide, and continue as part of the CapitalSource Division, with offices located in Chevy Chase, Maryland; Los Angeles, California; St. Louis, Missouri; Denver, Colorado; Chicago, Illinois; and New York, New York.
	The integration of CSB’s deposit system and the conversion of CSB’s branches to Pacific Western Bank’s operating platform were completed over the weekend of April 12, 2014. CSB had 21 branches, 12 of which were closed in the consolidation with Pacific Western at the close of business on April 11, 2014 and one overlapping Pacific Western branch was closed as well. All remaining branches opened on Monday, April 14, 2014 as Pacific Western branches.
	The CapitalSource Inc. merger has been accounted for under the acquisition method of accounting. The assets and liabilities, both tangible and intangible, were recorded at their estimated fair values as of the merger date. We made significant estimates and exercised significant judgment in estimating fair values and accounting for such acquired assets and liabilities. Such fair values are preliminary estimates and are subject to adjustment for up to one year after the merger date or when additional information relative to the closing date fair values becomes available and such information is considered final, whichever is earlier. The application of the acquisition method of accounting resulted in goodwill of $1.5 billion. All of the recognized goodwill is expected to be non‑deductible for tax purposes. The fair values of the acquired tax assets are still subject to change.
	As required by the merger agreement and as described in the joint proxy statement/prospectus relating to the merger, the Board of Directors of PacWest adopted a Tax Asset Protection Plan (the “Plan”). This Plan is similar to the Tax Benefit Preservation Plan that CapitalSource Inc. had in place prior to the merger. The purpose of the Plan is to seek to preserve PacWest’s ability to utilize net operating loss carryforwards and certain other tax assets (collectively, the “NOLs”) for U.S. federal income tax purposes that PacWest and certain of its subsidiaries have. The Plan seeks to protect the ability to utilize the NOLs by mitigating the potential for an “ownership change” within the meaning of Section 382 of the Internal Revenue Code of 1986, as amended (the “Code”).
	In general, an “ownership change” would occur if PacWest’s “5‑percent shareholders,” as defined under Section 382 of the Code, collectively increase their ownership in PacWest, in relation to their respective historical low points, by more than 50 percentage points over a rolling three‑year period. Institutional holders that file as “investment advisers” for SEC purposes, such as mutual fund companies that hold PacWest common stock on behalf of several individual mutual funds where no single fund owns five percent or more of PacWest’s common stock, generally are not treated as “5‑percent shareholders” for purposes of Section 382 of the Code.
	First California Financial Group Acquisition
	On May 31, 2013, we acquired First California Financial Group, Inc. As part of this acquisition, First California Bank ("FCB"), a wholly-owned subsidiary of FCAL, merged with and into Pacific Western. The FCAL acquisition has been accounted for under the acquisition method of accounting. The assets and liabilities, both tangible and intangible, were recorded at their estimated fair values as of the May 31, 2013 acquisition date. The application of the acquisition method of accounting resulted in goodwill of $129.1 million. All of the recognized goodwill is expected to be non‑deductible for tax purposes.
	FCB was a full‑service commercial bank headquartered in Westlake Village, California. FCB provided a full range of banking services, including revolving lines of credit, term loans, commercial real estate loans, construction loans, consumer loans and home equity loans to individuals, professionals, and small to mid‑sized businesses. FCB operated 15 branches throughout Southern California in the Los Angeles, Orange, Riverside, San Bernardino, San Diego, Ventura, and San Luis Obispo Counties. We completed the conversion and integration of the FCB branches to Pacific Western’s operating platform in June 2013 and as a result, we added seven locations to our branch network. We made this acquisition to expand our presence in Southern California.
	American Perspective Bank Acquisition
	On August 1, 2012, Pacific Western completed the acquisition of American Perspective Bank, or APB, previously headquartered in San Luis Obispo, California. Pacific Western acquired all of the outstanding common stock of APB for $58.1 million in cash and APB was merged with and into Pacific Western; we refer to this transaction as the APB acquisition. APB operated two branches located in San Luis Obispo and Santa Maria, California, and a loan production office located in Paso Robles, California, which has since been converted to a full‑service branch. The APB acquisition strengthened our presence in the Central Coast region.
	Celtic Capital Corporation Acquisition
	On April 3, 2012, Pacific Western completed the acquisition of Celtic Capital Corporation, or Celtic, an asset‑based lending company based in Santa Monica, California. Pacific Western acquired all of the capital stock of Celtic for $18.0 million in cash and Celtic became a wholly‑owned subsidiary of Pacific Western; we refer to this transaction as the Celtic acquisition. Celtic focuses on providing asset‑based loans to borrowers across the United States for amounts generally up to $5.0 million The Celtic acquisition diversified our lending portfolio, expanded our product lines, and deployed excess liquidity into higher yielding assets. In July 2014, we sold Celtic to an unaffiliated third party. As a result of the sale, we wrote-off goodwill of $6.6 million and the remaining CRI balance of $0.5 million.
	Pacific Western Equipment Finance Acquisition
	On January 3, 2012, Pacific Western completed the acquisition of Pacific Western Equipment Finance (formerly known as Marquette Equipment Finance, and which we refer to as EQF), an equipment leasing company based in Midvale, Utah. Pacific Western acquired all of the capital stock of EQF for $35.0 million in cash and EQF became a division of Pacific Western; we refer to this transaction as the EQF acquisition. The EQF acquisition diversified our loan portfolio, expanded our product lines, and deployed excess liquidity into higher yielding assets.
	Acquisition-Related Charges
	For each acquisition, we developed an integration plan for the Company that addressed, among other things, requirements for staffing, systems platforms, compliance-related activities, branch locations and other facilities. Based on these plans, we incurred acquisition-related charges which included severance, stock-based compensation, systems integration and facilities-related charges. These charges, along with legal, accounting, investment banking, valuation and other professional fees necessary to effect a business combination, were charged to acquisition, integration and reorganization costs on the consolidated statements of earnings. We incurred and charged to expense $101.0 million, $40.8 million and $4.1 million of such costs in 2014, 2013 and 2012.
	The following table presents acquisition, integration and reorganization costs by major category for the years indicated:
		Year Ended December 31,
		2014		2013		2012
		(In thousands)
	Severance and employee-related(1)	$	57,868	$	21,497	$	260
System conversion and integration	1,868		3,829		1,312
Asset writedowns, lease terminations and other facilities-related	6,353		3,212		—
Asset financing segment reorganization	10,073		—		—
Investment banking deal costs	16,117		5,309		1,298
Other (legal, accounting, insurance, consulting)	8,737		6,965		1,219
Total acquisition, integration and reorganization costs	$	101,016	$	40,812	$	4,089
__________________
-1	Amount includes $26.1 million in 2014 and $12.4 million in 2013 for accelerated vesting of restricted stock.
Unaudited Pro Forma Results of Operations
The following table presents our unaudited pro forma results of operations for the years presented as if the CapitalSource Inc. and FCAL acquisitions had been completed on January 1, 2013. The unaudited pro forma results of operations include the historical accounts of the Company, CapitalSource Inc. and FCAL and pro forma adjustments, including the amortization of intangibles with definite lives and the amortization or accretion of any premiums or discounts arising from fair value adjustments for assets acquired and liabilities assumed. The unaudited pro forma information is intended for informational purposes only and is not necessarily indicative of our future operating results or operating results that would have occurred had the CapitalSource Inc. and FCAL acquisitions been completed at the beginning of 2013. No assumptions have been applied to the pro forma results of operations regarding possible revenue enhancements, expense efficiencies or asset dispositions.
	Year Ended December 31,
	2014		2013
	(Dollars in thousands, except per share data)
Pro forma revenues (net interest income plus noninterest income)	$	797,296	$	833,373
Pro forma net earnings from continuing operations	$	252,258	$	251,347
Pro forma net earnings from continuing operations per share:
Basic	$	2.45	$	2.46
Diluted	$	2.45	$	2.46
Revenues and pre-tax net earnings from operations related to CapitalSource Inc. from the April 7, 2014 merger date through December 31, 2014, and included in the consolidated statement of earnings, were $400.6 million and $184.6 million.

Goodwill_and_Other_Intangible_

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	GOODWILL AND OTHER INTANGIBLE ASSETS
	The following table presents the changes in the carrying amount of goodwill for the years indicated:
		Goodwill
		(In thousands)
	Balance, December 31, 2011	$	39,141
	Addition from the EQF acquisition	19,033
	Addition from the Celtic acquisition	6,645
	Addition from the APB acquisition	15,047
	Balance, December 31, 2012	79,866
	Adjustment to APB goodwill	(193		)
	Addition from the FCAL acquisition	129,070
	Balance, December 31, 2013	208,743
	Addition from the CapitalSource Inc. merger	1,518,381
	Write-off due to the asset financing segment reorganization	(6,645		)
	Balance, December 31, 2014	$	1,720,479
	In the second quarter of 2014, we wrote-off $6.6 million of goodwill and $0.5 million of CRI related to the reorganization of the legacy PacWest asset financing segment, which included the sale of Celtic Capital Corporation. These amounts are included in "Acquisition, integration and reorganization costs" in the consolidated statements of earnings.
	The following table presents the changes in CDI and CRI and the related accumulated amortization for the years indicated:
		Year Ended December 31,
		2014			2013			2012
		(In thousands)
	Gross Amount of CDI and CRI:
	Balance, beginning of year	$	48,963		$	45,412		$	67,100
	Additions due to acquisitions	6,720			7,927			4,924
	Fully amortized portion	(1,293		)	(4,376		)	(20,746		)
	Write-off due to the asset financing segment reorganization	(1,300		)	—			—
	Removal due to branch sale	—			—			(5,866		)
	Balance, end of year	53,090			48,963			45,412
	Accumulated Amortization:
	Balance, beginning of year	(31,715		)	(30,689		)	(49,685		)
	Additions	(6,268		)	(5,402		)	(6,326		)
	Fully amortized portion	1,293			4,376			20,746
	Write-off due to the asset financing segment reorganization	804			—			—
	Removal due to branch sale	—			—			4,576
	Balance, end of period	(35,886		)	(31,715		)	(30,689		)
	Net CDI and CRI, end of year	$	17,204		$	17,248		$	14,723
	The weighted average amortization period remaining for all of our CDI and CRI is 4.6 years. The estimated aggregate amortization expense related to these intangible assets for each of the next five years is $6.0 million for 2015, $4.1 million for 2016, $2.3 million for 2017, $2.0 million for 2018 and $1.7 million for 2019.

Investments

Investments	12 Months Ended
	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Investment	INVESTMENTS
	Securities Available-for-Sale
	The following table presents amortized cost, gross unrealized gains and losses, and carrying values of securities available-for-sale as of the dates indicated:
		31-Dec-14											31-Dec-13
		Amortized Cost		Gross Unrealized Gains			Gross Unrealized Losses			Fair Value			Amortized Cost		Gross Unrealized Gains			Gross Unrealized Losses			Fair Value
		(In thousands)
	Residential mortgage-backed securities:
	Government agency and
	government-sponsored enterprise
	pass-through securities	$	515,902	$	20,142		$	(372	)	$	535,672		$	691,944	$	18,012		$	(2,768	)	$	707,188
	Government agency and
	government-sponsored enterprise
	collateralized mortgage obligations	275,513		3,513			(1,080		)	277,946			197,069		388			(4,584		)	192,873
	Covered private label collateralized
	mortgage obligations	26,889		7,153			(95		)	33,947			30,502		7,552			(150		)	37,904
	Other private label collateralized
	mortgage obligations	10,961		46			(93		)	10,914			—		—			—			—
	Municipal securities	521,499		15,899			(1,282		)	536,116			459,182		1,749			(24,273		)	436,658
	Corporate debt securities	110,074		597			(562		)	110,109			84,119		71			(1,483		)	82,707
	Government-sponsored enterprise debt
	securities	36,232		525			—			36,757			10,046		—			(174		)	9,872
	Other securities	25,801		33			(118		)	25,716			27,654		2			(113		)	27,543
	Total	$	1,522,871	$	47,908		$	(3,602	)	$	1,567,177		$	1,500,516	$	27,774		$	(33,545	)	$	1,494,745
	Other securities consist primarily of asset‑backed securities. See Note 14, Fair Value Measurements, for information on fair value measurements and methodology.
	As of December 31, 2014, securities available‑for‑sale with a carrying value of $308.6 million were pledged as collateral for borrowings, public deposits and other purposes as required by various statutes and agreements.
	During the year ended December 31, 2014, we sold $460.8 million of GSE pass-through securities and other securities for which we realized gains of $4.8 million. These securities were sold as part of our investment portfolio risk management activities. We also sold 322.7 million of the $382.8 million of securities obtained in the CapitalSource Inc. merger for no gain or loss. During the year ended December 31, 2013, we sold $12.4 million in corporate debt securities and $10.0 million in collateralized loan obligation securities for which we realized a gross gains of $409,000 and a gross loss of $272,000, respectively. The sale of the corporate debt securities was done as part of our portfolio risk management activities to reduce price volatility and duration. The sale of collateralized loan obligation securities was done in order to minimize our risk in holding these securities subject to the then proposed regulations referred to as the Volcker rule. During the year ended December 31, 2013, we also recorded a $5.2 million non-taxable gain to recognize our previously-held equity interest in FCAL common stock at its fair market value as of the acquisition date. During the year ended December 31, 2012, we sold $43.9 million of GSE pass-through securities as part of our portfolio risk management activities and realized a $1.2 million gross gain. We also sold $45.6 million of the $48.9 million of investment securities obtained in the APB acquisition for no gain or loss.
	During the years ended December 31, 2014, 2013 and 2012, we purchased $236.7 million, $550.2 million and $485.9 million in investment securities available-for-sale.
	Realized gains or losses resulting from the sale of securities are calculated using the specific identification method and included in gain on securities. During the years ended December 31, 2014, 2013 and 2012 we had $32.6 million, $(30.9) million and $10.2 million of net unrealized after-tax gains (losses) as a component of accumulated other comprehensive income, net.
	Unrealized Losses on Investment Securities
	The following tables present the gross unrealized losses and fair values of securities available-for-sale that were in unrealized loss positions, for which other-than-temporary impairments have not been recognized in earnings, as of the dates indicated:
		31-Dec-14
		Less Than 12 Months					12 Months or More						Total
		Fair Value		Gross Unrealized Losses			Fair Value			Gross Unrealized Losses			Fair Value		Gross Unrealized Losses
		(In thousands)
	Residential mortgage-backed securities:
	Government agency and government-
	sponsored enterprise pass-through
	securities	$	10,711	$	(13	)	$	27,100		$	(359	)	$	37,811	$	(372	)
	Government agency and government-
	sponsored enterprise collateralized
	mortgage obligations	23,908		(73		)	40,652			(1,007		)	64,560		(1,080		)
	Covered private label collateralized
	mortgage obligations	—		—			1,000			(95		)	1,000		(95		)
	Other private label collateralized
	mortgage obligations	1,618		(93		)	—			—			1,618		(93		)
	Municipal securities	11,854		(66		)	84,822			(1,216		)	96,676		(1,282		)
	Corporate debt securities	52,071		(547		)	10,131			(15		)	62,202		(562		)
	Other securities	6,440		(90		)	10,019			(28		)	16,459		(118		)
	Total	$	106,602	$	(882	)	$	173,724		$	(2,720	)	$	280,326	$	(3,602	)
		31-Dec-13
		Less Than 12 Months					12 Months or More						Total
		Fair Value		Gross Unrealized Losses			Fair Value			Gross Unrealized Losses			Fair Value		Gross Unrealized Losses
		(In thousands)
	Residential mortgage-backed securities:
	Government agency and government-
	sponsored enterprise pass-through
	securities	$	148,662	$	(2,767	)	$	32		$	(1	)	$	148,694	$	(2,768	)
	Government agency and government-
	sponsored enterprise collateralized
	mortgage obligations	179,938		(4,486		)	4,383			(98		)	184,321		(4,584		)
	Covered private label collateralized
	mortgage obligations	1,640		(60		)	617			(90		)	2,257		(150		)
	Municipal securities	337,208		(24,273		)	—			—			337,208		(24,273		)
	Corporate debt securities	72,636		(1,483		)	—			—			72,636		(1,483		)
Government-sponsored enterprise debt
securities	9,872		(174		)	—			—			9,872		(174		)
Other securities	23,969		(113		)	—			—			23,969		(113		)
Total	$	773,925	$	(33,356	)	$	5,032		$	(189	)	$	778,957	$	(33,545	)
We reviewed the securities that were in a loss position at December 31, 2014 and 2013, and concluded their losses were a result of the level of market interest rates relative to the types of securities and pricing changes caused by shifting supply and demand dynamics and not a result of downgraded credit ratings or other indicators of deterioration of the underlying issuers' ability to repay. Accordingly, we determined the securities were temporarily impaired and we did not recognize such impairment in the consolidated statements of earnings. We occasionally sell securities for risk management purposes to reduce risks related to price volatility and duration. We do not foresee having to sell these securities strictly for liquidity needs and believe that it is more likely than not we would not be required to sell these securities before recovery of their amortized cost.
During 2012, we determined that one covered private label CMO was impaired due to deteriorating cash flows and the depletion of the credit support from the subordinated classes of the securitization. We recorded an other-than-temporary impairment ("OTTO") loss of $1.1 million, which was entirely credited related, in the consolidated statements of earnings. This loss was offset by FDIC loss sharing income of $892,000, which represented the FDIC's 80% share of the loss. There were no OTTI losses recognized during 2014 and 2013.
Contractual Maturities
The following table presents the contractual maturities of our available-for-sale securities portfolio based on amortized cost and carrying value as of the date indicated.
	31-Dec-14
	Amortized Cost		Estimated Fair Value
	(In thousands)
Due in one year or less	$	4,567	$	4,596
Due after one year through five years	85,288		85,219
Due after five years through ten years	262,556		268,665
Due after ten years	1,170,460		1,208,697
Total securities available-for-sale	$	1,522,871	$	1,567,177
Mortgage-backed securities have contractual terms to maturity, but require periodic payments to reduce principal. In addition, expected maturities may differ from contractual maturities because obligors and/or issuers may have the right to call or prepay obligations with or without call or prepayment penalties.
FHLB Stock
At December 31, 2014, we had a $40.6 million investment in Federal Home Loan Bank of San Francisco ("FHLB") stock carried at cost. During the year ended December 31, 2014, FHLB stock increased $12.7 million due primarily to the addition of FHLB stock acquired in the CapitalSource Inc. merger. We evaluated the carrying value of our FHLB stock investment at December 31, 2014, and determined that it was not impaired. Our evaluation considered the long-term nature of the investment, the current financial and liquidity position of the FHLB, repurchase activity of excess stock by the FHLB at its carrying value, the return on the investment, and our intent and ability to hold this investment for a period of time sufficient to recover our recorded investment.
Interest Income on Investment Securities
The following table presents the composition of our interest income on investment securities for the years indicated:
	Year Ended December 31,
	2014		2013			2012
	(In thousands)
Taxable interest	$	30,135	$	23,542		$	29,652
Non-taxable interest	13,597		11,777			5,559
Dividend income	3,613		1,604			446
Total interest income on investment securities	$	47,345	$	36,923		$	35,657

Loans_and_Credit_Quality

Loans and Credit Quality	12 Months Ended
	Dec. 31, 2014
Receivables [Abstract]
Loans and Leases	LOANS AND LEASES
	The Company’s loan and lease portfolio includes originated and purchased loans and leases. Originated loans and leases and purchased loans and leases, in each case, for which there was no evidence of credit deterioration at their acquisition date and it was probable that we would be able to collect all contractually required payments, are referred to collectively as non-purchased credit impaired loans, or "Non-PCI loans." Purchased loans for which there was, at the acquisition date, evidence of credit deterioration since their origination and it was probable that we would be unable to collect all contractually required payments are referred to as purchased credit impaired loans, or "PCI loans".
	Non-PCI loans are carried at the principal amount outstanding, net of deferred fees and costs, and in the case of acquired loans, net of purchase discounts and premiums. Deferred fees and costs and purchase discounts and premiums on acquired non-impaired loans are recognized as an adjustment to interest income over the contractual life of the loans using the effective interest method or taken into income when the related loans are paid off or sold.
	PCI loans are accounted for in accordance with ASC Subtopic 310‑30, “Loans and Debt Securities Acquired with Deteriorated Credit Quality.” For PCI loans, at the time of acquisition we (i) calculate the contractual amount and timing of undiscounted principal and interest payments (the "undiscounted contractual cash flows") and (ii) estimate the amount and timing of undiscounted expected principal and interest payments (the "undiscounted expected cash flows"). The difference between the undiscounted contractual cash flows and the undiscounted expected cash flows is the nonaccretable difference. The difference between the undiscounted cash flows expected to be collected and the estimated fair value of the acquired loans is the accretable yield. The nonaccretable difference represents an estimate of the loss exposure of principal and interest related to the PCI loan portfolios; such amount is subject to change over time based on the performance of such loans. The carrying value of PCI loans is reduced by payments received, both principal and interest, and increased by the portion of the accretable yield recognized as interest income.
	In the CapitalSource Inc. merger, the estimated fair value of the loans and leases acquired, excluding PCI loans, was $6.8 billion, the related gross contractual cash flows was $9.4 billion, and the estimated contractual cash flows not expected to be collected was $839.8 million. The estimated fair value of loans acquired that were identified as PCI loans was $79.2 million.
	The following table summarizes the composition of our loan and lease portfolio as of the dates indicated:
		December 31, 2014												December 31, 2013
		Non-PCI												Non-PCI
		Loans				PCI								Loans				PCI
		and Leases				Loans				Total				and Leases				Loans			Total
		(In thousands)
	Real estate mortgage	$	5,350,827			$	256,489			$	5,607,316			$	2,424,864			$	371,134		$	2,795,998
	Real estate construction	309,162				6,924				316,086				209,090				10,427			219,517
	Commercial	5,852,420				27,155				5,879,575				1,241,776				974			1,242,750
	Consumer	101,423				284				101,707				54,809				261			55,070
	Total gross loans and leases	11,613,832				290,852				11,904,684				3,930,539				382,796			4,313,335
	Deferred fees and costs	(22,191		)		(61		)		(22,252		)		(983		)		—			(983		)
	Total loans and leases, net of unearned income	11,591,641				290,791				11,882,432				3,929,556				382,796			4,312,352
	Allowance for loan and lease losses	(70,456		)		(13,999		)		(84,455		)		(60,241		)		(21,793		)	(82,034		)
	Total net loans and leases	$	11,521,185			$	276,792			$	11,797,977			$	3,869,315			$	361,003		$	4,230,318
	The following table presents a summary of the activity in the allowance for credit losses on Non‑PCI loans and leases for the years indicated:
		Components								Total
		Non-PCI				Non-PCI				Non-PCI
		Allowance for				Reserve for				Allowance
		Loan and lease				Unfunded Loan				for Credit
		Losses				Commitments				Losses
		(In thousands)
	Balance, December 31, 2011	$	85,313			$	8,470			$	93,783
	Charge-offs	(13,070		)		—				(13,070		)
	Recoveries	3,406				—				3,406
	Negative provision	(9,750		)		(2,250		)		(12,000		)
	Balance, December 31, 2012	65,899				6,220				72,119
	Charge-offs	(11,159		)		—				(11,159		)
	Recoveries	6,856				—				6,856
	(Negative provision ) provision	(1,355		)		1,355				—
	Balance, December 31, 2013	60,241				7,575				67,816
	Charge-offs	(11,875		)		—				(11,875		)
	Recoveries	10,344				—				10,344
	(Negative provision) provision	11,746				(1,264		)		10,482
	Balance, December 31, 2014	$	70,456			$	6,311			$	76,767
	The following tables present a summary of the activity in the allowance for loan and lease losses on Non‑PCI loans and leases by portfolio segment and PCI loans for the years indicated:
		Year Ended December 31, 2014
		Real Estate Mortgage				Real Estate Construction				Commercial				Consumer				Total Non-PCI			Total PCI			Total
		(In thousands)
	Allowance for Loan and Lease Losses:
	Balance, beginning of year	$	26,078			$	4,298			$	26,921			$	2,944			$	60,241		$	21,793		$	82,034
	Charge-offs	(2,080		)		—				(9,463		)		(332		)		(11,875		)	(9,577		)	(21,452		)
	Recoveries	2,640				156				6,265				1,283				10,344			766			11,110
	Provision (negative provision)	(1,541		)		(206		)		16,135				(2,642		)		11,746			1,017			12,763
	Balance, end of year	$	25,097			$	4,248			$	39,858			$	1,253			$	70,456		$	13,999		$	84,455
	Amount of the allowance applicable to loans and leases:
	Individually evaluated for impairment	$	693			$	69			$	9,975			$	37			$	10,774
	Collectively evaluated for impairment	$	24,404			$	4,179			$	29,883			$	1,216			$	59,682
	Acquired loans with deteriorated credit quality																				$	13,999
	Loan and Leases:
	Ending balance(1)	$	5,340,560			$	307,135			$	5,842,463			$	101,483			$	11,591,641		$	290,791		$	11,882,432
	The ending balance of the loan and lease portfolio is composed of loans and leases:
	Individually evaluated for impairment	$	57,857			$	10,555			$	46,709			$	3,744			$	118,865
	Collectively evaluated for impairment	$	5,282,703			$	296,580			$	5,795,754			$	97,739			$	11,472,776
	Acquired loans with deteriorated credit quality																				$	290,791
	_________________________
	-1	As of December 31, 2014, the amounts of loans covered by loss sharing provisions of FDIC loss sharing agreements in the Non-PCI and PCI categories were $61.5 million and $100.4 million.
		Year Ended December 31, 2013
		Real Estate Mortgage				Real Estate Construction				Commercial				Consumer				Total Non-PCI			Total PCI			Total
	(In thousands)
Allowance for loan and lease losses:
Balance, beginning of year	$	38,700			$	3,221			$	22,252			$	1,726			$	65,899		$	26,069		$	91,968
Charge-offs	(4,552		)		—				(6,409		)		(198		)		(11,159		)	(66		)	(11,225		)
Recoveries	2,507				1,654				2,621				74				6,856			—			6,856
Provision (negative provision)	(10,577		)		(577		)		8,457				1,342				(1,355		)	(4,210		)	(5,565		)
Balance, end of year	$	26,078			$	4,298			$	26,921			$	2,944			$	60,241		$	21,793		$	82,034
Amount of the allowance applicable to loans and leases:
Individually evaluated for impairment	$	2,188			$	169			$	5,003			$	240			$	7,600
Collectively evaluated for impairment	$	23,890			$	4,129			$	21,918			$	2,704			$	52,641
Acquired loans with deteriorated credit quality																				$	21,793
Loan and Leases:
Ending balance(1)	$	2,422,107			$	207,779			$	1,244,785			$	54,885			$	3,929,556		$	382,796		$	4,312,352
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated for impairment	$	62,276			$	7,512			$	17,932			$	702			$	88,422
Collectively evaluated for impairment	$	2,359,831			$	200,267			$	1,226,853			$	54,183			$	3,841,134
Acquired loans with deteriorated credit quality																				$	382,796
_________________________
-1	As of December 31, 2013, the amounts of loans covered by loss sharing provisions of FDIC loss sharing agreements in the Non-PCI and PCI categories were $85.9 million and $362.5 million.
Non‑Purchased Credit Impaired (Non‑PCI) Loans and Leases
The following table presents the credit risk rating categories for Non‑PCI loans and leases by portfolio segment and class as of the dates indicated. Nonclassified loans and leases are those with a credit risk rating of either pass or special mention, while classified loans and leases are those with a credit risk rating of either substandard or doubtful.
	31-Dec-14												December 31, 2013
	Classified				Nonclassified				Total				Classified				Nonclassified			Total
	(In thousands)
Real estate mortgage:
Hospitality	$	17,761			$	542,458			$	560,219			$	12,337			$	168,216		$	180,553
SBA	11,141				364,786				375,927				5,297				39,869			45,166
Other	68,084				4,336,330				4,404,414				64,279				2,132,109			2,196,388
Total real estate mortgage	96,986				5,243,574				5,340,560				81,913				2,340,194			2,422,107
Real estate construction:
Residential	402				96,326				96,728				750				58,131			58,881
Commercial	3,346				207,061				210,407				6,291				142,607			148,898
Total real estate construction	3,748				303,387				307,135				7,041				200,738			207,779
Commercial:
Collateralized	22,433				416,754				439,187				18,838				567,643			586,481
Unsecured	1,323				130,501				131,824				1,856				151,896			153,752
Asset-based	11,547				1,783,304				1,794,851				6,859				195,569			202,428
Cash flow	83,321				2,376,530				2,459,851				—				—			—
Equipment finance	15,973				953,516				969,489				632				272,851			273,483
SBA	3,207				44,054				47,261				5,761				22,880			28,641
Total commercial	137,804				5,704,659				5,842,463				33,946				1,210,839			1,244,785
Consumer	4,073				97,410				101,483				4,411				50,474			54,885
Total Non-PCI loans and leases	$	242,611			$	11,349,030			$	11,591,641			$	127,311			$	3,802,245		$	3,929,556
In addition to our internal risk rating process, our federal and state banking regulators, as an integral part of their examination process, periodically review the Company’s loan risk rating classifications. Our regulators may require the Company to recognize rating downgrades based on their judgments related to information available to them at the time of their examinations. Risk rating downgrades generally result in increases in the provisions for credit losses and the allowance for credit losses.
The following tables present an aging analysis of our Non‑PCI loans and leases by portfolio segment and class as of the dates indicated:
	31-Dec-14
	30-89 Days Past Due				90 or More				Total Past Due				Current				Total Loans
					Days Past Due
	(In thousands)
Real estate mortgage:
Hospitality	$	—			$	—			$	—			$	560,219			$	560,219
SBA	5,530				4,357				9,887				366,040				375,927
Other	6,098				7,630				13,728				4,390,686				4,404,414
Total real estate mortgage	11,628				11,987				23,615				5,316,945				5,340,560
Real estate construction:
Residential	—				—				—				96,728				96,728
Commercial	—				715				715				209,692				210,407
Total real estate construction	—				715				715				306,420				307,135
Commercial:
Collateralized	878				965				1,843				437,344				439,187
Unsecured	69				45				114				131,710				131,824
Asset-based	—				—				—				1,794,851				1,794,851
Cash flow	—				232				232				2,459,619				2,459,851
Equipment finance	6,525				366				6,891				962,598				969,489
SBA	205				1,362				1,567				45,694				47,261
Total commercial	7,677				2,970				10,647				5,831,816				5,842,463
Consumer	101				3,146				3,247				98,236				101,483
Total Non-PCI loans and leases	$	19,406			$	18,818			$	38,224			$	11,553,417			$	11,591,641
	31-Dec-13
	30-89 Days Past Due				90 or More				Total Past Due				Current				Total Loans
					Days Past Due
	(In thousands)
Real estate mortgage:
Hospitality	$	—			$	—			$	—			$	180,553			$	180,553
SBA	2,564				—				2,564				42,602				45,166
Other	13,026				2,406				15,432				2,180,956				2,196,388
Total real estate mortgage	15,590				2,406				17,996				2,404,111				2,422,107
Real estate construction:
Residential	—				—				—				58,881				58,881
Commercial	—				2,013				2,013				146,885				148,898
Total real estate construction	—				2,013				2,013				205,766				207,779
Commercial:
Collateralized	473				259				732				585,749				586,481
Unsecured	83				68				151				153,601				153,752
Asset-based	—				—				—				202,428				202,428
Equipment finance	2,662				244				2,906				270,577				273,483
SBA	1,770				243				2,013				26,628				28,641
Total commercial	4,988				814				5,802				1,238,983				1,244,785
Consumer	3,319				—				3,319				51,566				54,885
Total Non-PCI loans and leases	$	23,897			$	5,233			$	29,130			$	3,900,426			$	3,929,556
At December 31, 2014 and 2013, the Company had no loans and leases (excluding PCI loans) that were greater than 90 days past due and still accruing interest. It is the Company’s policy to discontinue accruing interest when principal or interest payments are past due 90 days or more unless the loan is both well secured and in the process of collection or when, in the opinion of management, there is a reasonable doubt as to the collectability of a loan or lease in the normal course of business. For 2014, the amount of interest income that would have been recorded on nonaccrual loans and leases at December 31, 2014 had such loans and leases been current in accordance with their original terms was $7.5 million.
The following table presents our nonaccrual and performing Non‑PCI loans and leases by portfolio segment and class as of the dates indicated:
	31-Dec-14												31-Dec-13
	Nonaccrual				Performing				Total				Nonaccrual				Performing			Total
	(In thousands)
Real estate mortgage:
Hospitality	$	6,366			$	553,853			$	560,219			$	6,723			$	173,830		$	180,553
SBA	11,141				364,786				375,927				2,602				42,564			45,166
Other	20,105				4,384,309				4,404,414				18,648				2,177,740			2,196,388
Total real estate mortgage	37,612				5,302,948				5,340,560				27,973				2,394,134			2,422,107
Real estate construction:
Residential	381				96,347				96,728				389				58,492			58,881
Commercial	1,178				209,229				210,407				2,830				146,068			148,898
Total real estate construction	1,559				305,576				307,135				3,219				204,560			207,779
Commercial:
Collateralized	5,450				433,737				439,187				9,991				576,490			586,481
Unsecured	639				131,185				131,824				458				153,294			153,752
Asset-based	4,574				1,790,277				1,794,851				1,070				201,358			202,428
Cash flow	15,964				2,443,887				2,459,851				—				—			—
Equipment finance	11,131				958,358				969,489				632				272,851			273,483
SBA	3,207				44,054				47,261				3,037				25,604			28,641
Total commercial	40,965				5,801,498				5,842,463				15,188				1,229,597			1,244,785
Consumer	3,485				97,998				101,483				394				54,491			54,885
Total Non-PCI loans and leases	$	83,621			$	11,508,020			$	11,591,641			$	46,774			$	3,882,782		$	3,929,556
At December 31, 2014, nonaccrual loans and leases totaled $83.6 million. Nonaccrual loans and leases included all loans and leases 90 or more days past due of $18.8 million, $8.7 million of loans 30 to 89 days past due and $56.1 million of current loans that were placed on nonaccrual status based on management’s judgment regarding their collectability. Nonaccrual loans and leases totaled $46.8 million at December 31, 2013, including all loans and leases 90 or more days past due of $5.2 million, $4.2 million of loans 30 to 89 days past due and $37.3 million of current loans that were placed on nonaccrual status based on management’s judgment regarding their collectability.
Non‑PCI nonaccrual loans and leases and performing restructured loans are considered impaired for reporting purposes. The following table presents the composition of our impaired loans and leases as of the dates indicated:
	December 31, 2014												December 31, 2013
					Performing				Total								Performing			Total
	Nonaccrual				Restructured				Impaired				Nonaccrual				Restructured			Impaired
	Loans/Leases				Loans				Loans/Leases				Loans/Leases				Loans			Loans/Leases
	(In thousands)
Real estate mortgage	$	37,612			$	20,245			$	57,857			$	27,973			$	34,303		$	62,276
Real estate construction	1,559				8,996				10,555				3,219				4,293			7,512
Commercial	40,965				5,744				46,709				15,188				2,744			17,932
Consumer	3,485				259				3,744				394				308			702
Total	$	83,621			$	35,244			$	118,865			$	46,774			$	41,648		$	88,422
At December 31, 2014 and 2013, we had unfunded commitments related to Non-PCI performing restructured loans of $214,000 and $7,000.
The following tables present information regarding our Non‑PCI impaired loans and leases by portfolio segment and class as of and for the years indicated:
	31-Dec-14												31-Dec-13
	Recorded Investment				Unpaid Principal Balance				Related				Recorded Investment				Unpaid Principal Balance			Related
									Allowance											Allowance
	(In thousands)
With An Allowance Recorded:
Real estate mortgage:
Hospitality	$	1,946			$	1,945			$	47			$	5,717			$	6,215		$	198
SBA	—				—				—				1,642				1,643			230
Other	9,136				9,233				646				15,937				16,571			1,760
Real estate construction:
Residential	763				763				46				778				778			168
Commercial	1,128				4,934				23				1,250				1,250			1
Commercial:
Collateralized	4,630				5,246				3,771				4,377				4,692			4,270
Unsecured	912				924				799				801				829			375
Asset-based	137				247				137				1,070				1,070			180
Cash flow	15,578				17,970				2,667				—				—			—
Equipment finance	6,956				7,268				2,601				—				—			—
SBA	—				—				—				1,136				1,136			178
Consumer	143				142				37				424				471			240
With No Related Allowance Recorded:
Real estate mortgage:
Hospitality	$	6,366			$	7,593			$	—			$	3,013			$	3,385		$	—
SBA	11,141				14,708				—				2,602				3,646			—
Other	29,268				40,643				—				33,365				46,062			—
Real estate construction:
Residential	21				19				—				—				—			—
Commercial	8,643				8,749				—				5,484				9,923			—
Commercial:
Collateralized	5,566				6,877				—				6,700				9,924			—
Unsecured	725				809				—				179				247			—
Asset-based	4,436				5,415				—				—				—			—
Cash flow	387				919				—				—				—			—
Equipment finance	4,175				7,528				—				632				632			—
SBA	3,207				4,920				—				3,037				4,945			—
Consumer	3,601				3,768				—				278				394			—
Total Non-PCI Loans and Leases With and Without an Allowance Recorded:
Real estate mortgage	$	57,857			$	74,122			$	693			$	62,276			$	77,522		$	2,188
Real estate construction	10,555				14,465				69				7,512				11,951			169
Commercial	46,709				58,123				9,975				17,932				23,475			5,003
Consumer	3,744				3,910				37				702				865			240
Total	$	118,865			$	150,620			$	10,774			$	88,422			$	113,813		$	7,600
	Year Ended December 31,
	2014								2013								2012
	Weighted Average				Interest				Weighted Average				Interest				Weighted Average			Interest
	Balance(1)				Income				Balance(1)				Income				Balance(1)			Income
					Recognized								Recognized							Recognized
	(In thousands)
With An Allowance Recorded:
Real estate mortgage:
Hospitality	$	1,946			$	67			$	5,717			$	81			$	8,954		$	80
SBA	—				—				1,642				90				827			41
Other	9,136				409				13,205				509				51,441			2,070
Real estate construction:
Residential	763				15				778				14				1,303			11
Commercial	1,027				17				1,250				63				6,723			231
Commercial:
Collateralized	4,077				27				3,281				29				2,219			48
Unsecured	661				21				772				33				2,273			20
Asset-based	137				—				569				—				—			—
Cash flow	7,837				—				—				—				—			—
Equipment finance	3,802				—				—				—				—			—
SBA	—				—				1,136				56				2,593			53
Consumer	132				8				425				10				389			7
With No Related Allowance Recorded:
Real estate mortgage:
Hospitality	$	6,366			$	—			$	3,013			$	—			$	—		$	—
SBA	6,610				77				2,601				—				1,472			—
Other	21,652				315				27,912				1,060				29,316			1,523
Real estate construction:
Residential	4				—				—				—				—			—
Commercial	8,642				244				4,866				11				17,424			589
Commercial:
Collateralized	2,869				170				3,410				20				1,657			27
Unsecured	126				1				157				—				148			—
Asset-based	3,270				—				—				—				132			—
Cash flow	1				—				—				—				—			—
Equipment finance	2,534				—				245				—				224			—
SBA	2,162				98				2,571				—				2,601			24
Consumer	3,027				2				161				—				136			—
Total Non-PCI Loans and Leases With and Without an Allowance Recorded:
Real estate mortgage	$	45,710			$	868			$	54,090			$	1,740			$	92,010		$	3,714
Real estate construction	10,436				276				6,894				88				25,450			831
Commercial	27,476				317				12,141				138				11,847			172
Consumer	3,159				10				586				10				525			7
Total	$	86,781			$	1,471			$	73,711			$	1,976			$	129,832		$	4,724
_________________________
-1	For the loans and leases (excluding PCI loans) reported as impaired at December 31, 2014, 2013 and 2012, amounts were calculated based on the period of time such loans and leases were impaired during the reported period.
Troubled debt restructurings are a result of rate reductions, term extensions, fee concessions and debt forgiveness or a combination thereof. The following table presents new and defaulted troubled debt restructurings of Non-PCI loans for the years indicated:
	Troubled Debt Restructurings											Troubled Debt Restructurings That Subsequently Defaulted(1)
	Number of Loans			Pre- Modification Outstanding Recorded Investment				Post-Modification Outstanding Recorded Investment				Number of Loans			Recorded Investment
	(Dollars In thousands)
Year Ended December 31, 2014
Real estate mortgage:
Hospitality	1			$	1,946			$	1,946			—			$	—
SBA	1			64				64				1			55
Other	23			17,443				17,444				—			—
Real estate construction - Commercial	4			5,507				4,965				—			—
Commercial:
Collateralized	22			12,368				6,336				1			390
Unsecured	10			752				752				—			—
Equipment finance	1			518				518				—			—
SBA	3			1,965				1,965				1			1,144
Consumer	7			467				467				—			—
Total	72			$	41,030			$	34,457			3			$	1,589		-2
Year Ended December 31, 2013
Real estate mortgage - Other	14			$	16,223			$	16,223			2			$	1,844
Real estate construction - Residential	1			390				390				—			—
Commercial:
Collateralized	11			5,618				5,618				1			419
Unsecured	5			521				521				2			66
Asset-based	1			2,032				2,032				1			1,070
SBA	4			137				137				—			—
Consumer	2			125				125				—			—
Total	38			$	25,046			$	25,046			6			$	3,399		-3
Year Ended December 31, 2012
Real estate mortgage:
SBA	2			$	1,680			$	1,680			—			$	—
Other	8			14,861				13,840				—			—
Real estate construction - Other	3			6,919				6,919				—			—
Commercial:
Collateralized	7			1,652				1,652				2			458
Unsecured	5			317				317				—			—
SBA	4			1,216				1,216				1			873
Consumer	1			206				206				—			—
Total	30			$	26,851			$	25,830			3			$	1,331		-4
_________________________
-1	The population of defaulted restructured loans for the period indicated includes only those loans restructured during the preceding 12-month period. The table excludes defaulted troubled restructurings in those classes for which the recorded investment was zero at the end of the period.
-2	Represents the balance at December 31, 2014, and is net of charge-offs of $129,000.
-3	Represents the balance at December 31, 2013, and is net of charge-offs of $1.6 million.
-4	Represents the balance at December 31, 2012, and is net of charge-offs of $921,000.
Purchased Credit Impaired (PCI) Loans
The following table reflects the PCI loans by portfolio segment as of the dates indicated:
	December 31, 2014				December 31, 2013
	(In thousands)
Real estate mortgage	$	299,660			$	412,791
Real estate construction	7,743				12,015
Commercial	32,904				3,021
Consumer	332				424
Total gross PCI loans	340,639				428,251
Less:
Discount	(49,848		)		(45,455		)
Allowance for loan losses	(13,999		)		(21,793		)
Total net PCI loans	$	276,792			$	361,003
The following table summarizes the changes in the carrying amount of PCI loans and accretable yield on those loans for the years indicated:
	Carrying Amount				Accretable Yield
	(In thousands)
Balance, December 31, 2011	$	674,058			$	(259,265	)
Accretion	49,562				49,562
Payments received	(232,623		)		—
Decrease in expected cash flows, net	—				13,681
Negative provision for credit losses	819				—
Balance, December 31, 2012	491,816				(196,022		)
Addition from the FCAL acquisition	44,146				(8,096		)
Accretion	46,680				46,680
Payments received	(225,849		)		—
Decrease in expected cash flows, net	—				17,870
Negative provision for credit losses	4,210				—
Balance, December 31, 2013	361,003				(139,568		)
Addition from the CapitalSource merger	79,234				(13,728		)
Accretion	57,213				57,213
Payments received	(219,641		)		—
Increase in expected cash flows, net	—				(10,773		)
Provision for credit losses	(1,017		)		—
Balance, December 31, 2014	$	276,792			$	(106,856	)
The following table summarizes the accretable yield on the PCI loans acquired in the CapitalSource Inc. merger as of April 7, 2014:
	April 7, 2014
	Accretable Yield
	(In thousands)
Undiscounted contractual cash flows	$	231,832
Undiscounted cash flows not expected to be collected (nonaccretable difference)	(138,870		)
Undiscounted cash flows expected to be collected	92,962
Estimated fair value of PCI loans acquired	(79,234		)
Accretable yield	$	13,728
The following table presents the credit risk rating categories for PCI loans by portfolio segment as of the dates indicated. Nonclassified loans are those with a credit risk rating of either pass or special mention, while classified loans are those with a credit risk rating of either substandard or doubtful.
	31-Dec-14												31-Dec-13
	Nonclassified				Classified				Total				Nonclassified				Classified			Total
	(In thousands)
Real estate mortgage	$	155,281			$	101,161			$	256,442			$	216,092			$	155,042		$	371,134
Real estate construction	3,010				3,901				6,911				4,399				6,028			10,427
Commercial	212				26,942				27,154				569				405			974
Consumer	—				284				284				—				261			261
Total PCI loans	$	158,503			$	132,288			$	290,791			$	221,060			$	161,736		$	382,796
In addition to our internal risk rating process, our federal and state banking regulators, as an integral part of their examination process, periodically review the Company’s loan risk rating classifications. Our regulators may require the Company to recognize rating downgrades based on their judgments related to information available to them at the time of their examinations.

Foreclosed_Assets_Foreclosed_A

Foreclosed Assets Foreclosed Assets	12 Months Ended
	Dec. 31, 2014
Other Real Estate Owned Net Covered and NonCovered Including Foreclosed Assets [Abstract]
Foreclosed Assets	FORECLOSED ASSETS
	The following table summarizes foreclosed assets at the dates indicated:
	Property Type:	31-Dec-14			31-Dec-13
		(In thousands)
	Commercial real estate	$	2,449		$	15,753
	Construction and land development	24,759			35,063
	Multi‑family	4,823			835
	Single family residence	3,392			186
	Total other real estate owned, net	35,423			51,837
	Other foreclosed assets	8,298			4,054
	Total foreclosed assets, net(1)	$	43,721		$	55,891
	_________________________
	-1	As of December 31, 2014 and 2013, the amounts of covered foreclosed assets were $9.3 million and $9.0 million.
	The following table presents the changes in foreclosed assets, net of the valuation allowance, for the years indicated:
		Year Ended December 31,
		2014			2013			2012
	Foreclosed Assets:	(In thousands)
	Balance, beginning of year	$	55,891		$	56,414		$	81,918
	Addition due to acquisitions	6,382			13,772			1,561
	Foreclosures	9,806			19,470			40,207
	Provision for losses	(7,307		)	(2,515		)	(14,333		)
	Reductions related to sales	(21,051		)	(31,289		)	(53,828		)
	Payments to third parties(1)	—			39			889
	Balance, end of year	$	43,721		$	55,891		$	56,414
	_________________________
	-1	Represents amounts due to participants and for guarantees, property taxes or other prior lien positions.
	The following table presents the changes in the foreclosed assets valuation allowance for the years indicated:
		Year Ended December 31,
		2014			2013			2012
	Foreclosed Assets Valuation Allowance:	(In thousands)
	Balance, beginning of year	$	11,314		$	16,681		$	20,575
	Provision for losses	7,307			2,515			14,333
	Reductions related to sales	(6,498		)	(7,882		)	(19,103		)
	Selling costs(1)	—			—			876
	Balance, end of year	$	12,123		$	11,314		$	16,681
	_________________________
	-1	During 2011, the FDIC changed its methodology such that selling costs are reimbursed at the time of sale rather than at the time of foreclosure. Such amounts will be realized when the related OREO parcels are sold.

FDIC_Loss_Sharing_Asset_FDIC_L

FDIC Loss Sharing Asset FDIC Loss Sharing Asset	12 Months Ended
	Dec. 31, 2014
FDIC Loss-Sharing Arrangements [Abstract]
FDIC Loss Sharing Asset	FDIC LOSS SHARING ASSET
	We are a party to four loss sharing agreements with the FDIC. Such agreements cover a substantial portion of losses incurred on acquired covered loans and other real estate owned. The loss sharing agreements relate to the acquisitions of: (1) Affinity Bank ("Affinity") in August 2009, (2) Los Padres Bank ("Los Padres") in August 2010, (3) Western Commercial Bank ("Western Commercial") in connection with the May 2013 FCAL acquisition, and (4) San Luis Trust Bank ("San Luis") in connection with the May 2013 FCAL acquisition. Generally, under the terms of the loss sharing agreements, the FDIC is responsible for 80% of losses in connection with covered assets and is entitled to receive 80% of loss recoveries on the covered assets during the applicable contractual periods. The loss sharing provisions for the Affinity Bank non-single family covered assets expired in the third quarter of 2014; accordingly, further activity will be limited to recoveries through the third quarter of 2017 for assets covered by this loss sharing agreement.
	Both the Western Commercial and San Luis loss sharing agreements contain true-up provisions, under which we will owe the FDIC amounts at the end of the loss sharing agreements based on the performance of the covered assets. The true-up liability is included in other liabilities in the accompanying consolidated balance sheets.
	The following table presents the changes in the FDIC loss sharing asset for the years indicated:
		Year Ended December 31,
		2014			2013			2012
		(In thousands)
	Balance, beginning of year	$	45,524		$	57,475		$	95,187
	Addition from the FCAL acquisition	—			17,241			—
	FDIC share of additional losses, net of recoveries	(4,941		)	4,969			6,169
	Cash paid to (received from) FDIC	3,202			(7,332		)	(33,223		)
	Net amortization	(25,051		)	(26,829		)	(10,658		)
	Balance, end of year	$	18,734		$	45,524		$	57,475
	The following table presents information about the composition of the FDIC loss sharing asset, the true‑up liability, and the non‑single family and the single family covered assets as of the date indicated:
		31-Dec-14
		Affinity Bank			Los Padres Bank			Western Commercial Bank			San Luis Trust Bank		Total
		(In thousands)
	FDIC loss sharing asset	$	(302	)	$	9,435		$	1,165		$	8,436	$	18,734
	True‑up liability	N/A			N/A			$	1,753		$	5,433	$	7,186
	Non-single family covered assets (1)	$	113,361		$	77,814		$	11,327		$	28,555	$	231,057
	Single family covered assets	$	10,987		$	56,891		N/A			$	30,517	$	98,395
	Loss sharing expiration dates:
	Non‑single family	3rd Quarter 2014			3rd Quarter 2015			4th Quarter 2015			1st Quarter 2016
	Single family	3rd Quarter 2019			3rd Quarter 2020			N/A			1st Quarter 2021
	Loss recovery expiration dates:
	Non‑single family	3rd Quarter 2017			3rd Quarter 2018			4th Quarter 2018			1st Quarter 2019
	Single family	3rd Quarter 2019			3rd Quarter 2020			N/A			1st Quarter 2021
	__________________
	-1	Excludes securities.

Premises_and_Equipment_Net

Premises and Equipment, Net	12 Months Ended
	Dec. 31, 2014
Premises and Equipment, Net [Abstract]
Premises and Equipment, Net	PREMISES AND EQUIPMENT, NET
	The following table presents the components of premises and equipment as of the dates indicated:
		December 31,
		2014			2013
		(In thousands)
	Land	$	5,505		$	6,755
	Buildings	14,198			12,725
	Furniture, fixtures and equipment	32,359			31,080
	Leasehold improvements	33,157			26,091
	Premises and equipment, gross	85,219			76,651
	Less: accumulated depreciation and amortization	(48,668		)	(44,216		)
	Premises and equipment, net	$	36,551		$	32,435
	Depreciation and amortization expense was $8.4 million, $6.0 million, and $5.4 million for the years ended December 31, 2014, 2013, and 2012.
	We have obligations under a number of noncancelable operating leases for premises and equipment. The following table presents future minimum rental payments under noncancelable operating leases as of December 31, 2014:
	Estimated Lease Payments for Year Ending December 31,	Amount
		(In thousands)
	2015	$	26,767
	2016	22,978
	2017	20,009
	2018	17,293
	2019	13,626
	Thereafter	43,943
	Total	$	144,616
	Total gross rental expense for the years ended December 31, 2014, 2013, and 2012, was $23.8 million, $17.6 million, $16.8 million. Most of the leases provide that the Company pays maintenance, insurance and certain other operating expenses applicable to the leased premises in addition to the monthly rental payments.
	Total rental income for the years ended December 31, 2014, 2013, and 2012, was approximately $589,000, $750,000, and $505,000. The future minimum rental payments to be received under noncancelable subleases are $29.3 million.

Deposits

Deposits	12 Months Ended
	Dec. 31, 2014
Deposits [Abstract]
Deposits	DEPOSITS
	The following table presents the components of interest‑bearing deposits as of the dates indicated:
		December 31,
	Deposit Category	2014		2013
		(In thousands)
	Interest checking deposits	$	736,367	$	620,622
	Money market deposits	1,825,510		1,458,910
	Savings deposits	762,961		218,638
	Time deposits under $100,000	2,467,338		225,360
	Time deposits $100,000 and over	3,031,600		439,011
	Total interest-bearing deposits	$	8,823,776	$	2,962,541
	Brokered time deposits totaled $636.7 million and $49.4 million at December 31, 2014 and 2013. Brokered time deposits under the CDARS Program totaled $44.0 million and $49.4 million at December 31, 2014 and December 31, 2013. The CDARS Program represents deposits that are participated with other FDIC‑insured financial institutions as a means to provide FDIC deposit insurance coverage for the full amount of our customers’ deposits.
	The following table summarizes the maturities of time deposits as of the date indicated:
		31-Dec-14
	Year of Maturity	Time		Time		Total		Rate
		Deposits		Deposits		Time
		Under		$100,000		Deposits
		$100,000		or More
		(Dollars in thousands)
	2015	$	2,233,704	$	2,724,756	4,958,460		0.72	%
	2016	176,125		248,533		424,658		1.01	%
	2017	32,047		36,778		68,825		0.84	%
	2018	20,272		15,067		35,339		1.13	%
	2019	4,880		6,466		11,346		1.03	%
	2020	310		—		310		0.78	%
	Total	$	2,467,338	$	3,031,600	$	5,498,938	0.75	%

Borrowings_and_Subordinated_De

Borrowings and Subordinated Debentures	12 Months Ended
	Dec. 31, 2014
Borrowings Subordinated Debentures And Brokered Deposits [Abstract]
Borrowings and Subordinated Debentures	BORROWINGS AND SUBORDINATED DEBENTURES
	Borrowings
	The following table summarizes our borrowings as of the dates indicated:
		December 31, 2014					December 31, 2013
		Amount			Rate		Amount			Rate
		(Dollars in thousands)
	Non‑recourse debt	$	3,402		6.43	%	$	7,126		6.3	%
	FHLB overnight advances	380,000			0.27	%	106,600			0.06	%
	Total borrowings	$	383,402				$	113,726
	The non‑recourse debt represents the payment stream of certain equipment leases sold to third parties. The debt is secured by the equipment in the leases and all interest rates are fixed. As of December 31, 2014, this debt had a weighted average remaining maturity of 2.3 years .
	On October 1, 2014, the holding company obtained an unsecured, variable-rate revolving line of credit in the amount of $75.0 million with an expiration date of September 30, 2015. This borrowing facility provides additional available liquidity to the Company. As of December 31, 2014, there was no balance outstanding.
	The Bank has established secured and unsecured lines of credit. We may borrow funds from time to time on a term or overnight basis from the FHLB, the Federal Reserve Bank of San Francisco (“FRBSF”), or other financial institutions.
	FHLB Secured Lines of Credit. The borrowing arrangement with the FHLB is based on an FHLB program collateralized by a blanket lien on certain qualifying loans in our loan portfolio which were not pledged to the FRBSF. As of December 31, 2014, our borrowing capacity under the FHLB secured borrowing lines was $2.4 billion. As of December 31, 2014 and December 31, 2013, the balances outstanding were $380.0 million and $106.6 million.
	FRBSF Secured Line of Credit. The Bank has a secured line of credit with the FRBSF. As of December 31, 2014, the Bank had secured borrowing capacity of $1.3 billion collateralized by liens covering $1.8 billion of certain qualifying loans. As of December 31, 2014 and December 31, 2013, there were no balances outstanding.
	Federal Funds Arrangements with Commercial Banks. As of December 31, 2014, the Bank had unsecured lines of credit of $80.0 million with correspondent banks for the purchase of overnight funds, subject to availability of funds. These lines are renewable annually and have no unused commitment fees. As of December 31, 2014 and December 31, 2013, there were no balances outstanding.
	The following table summarizes the terms of each issuance of subordinated debentures outstanding as of the dates indicated:
		31-Dec-14					31-Dec-13
												Date	Maturity	Rate Index
	Series	Amount			Rate (1)		Amount			Rate (2)		Issued	Date	(Quarterly Reset)
		(Dollars in thousands)
	Trust V	$	10,310		3.33	%	$	10,310		3.34	%	8/15/03	9/17/33	3 month LIBOR + 3.10
	Trust VI	10,310			3.29	%	10,310			3.29	%	9/3/03	9/15/33	3 month LIBOR + 3.05
	Trust CII	5,155			3.19	%	5,155			3.19	%	9/17/03	9/17/33	3 month LIBOR + 2.95
	Trust VII	61,856			2.98	%	61,856			2.99	%	2/5/04	4/23/34	3 month LIBOR + 2.75
	Trust CIII	20,619			1.93	%	20,619			1.93	%	8/15/05	9/15/35	3 month LIBOR + 1.69
	Trust FCCI	16,495			1.84	%	16,495			1.84	%	1/25/07	3/15/37	3 month LIBOR + 1.60
	Trust FCBI	10,310			1.79	%	10,310			1.79	%	9/30/05	12/15/35	3 month LIBOR + 1.55
	Trust CS 2005-1 (3)	82,475			2.19	%	—			—		11/21/05	12/15/35	3 month LIBOR + 1.95
	Trust CS 2005-2 (3)	128,866			2.18	%	—			—		12/14/05	1/30/36	3 month LIBOR + 1.95
	Trust CS 2006-1 (3)	51,545			2.18	%	—			—		2/22/06	4/30/36	3 month LIBOR + 1.95
	Trust CS 2006-2 (3)	51,550			2.18	%	—			—		9/27/06	10/30/36	3 month LIBOR + 1.95
	Trust CS 2006-3 (3)(4)	31,188			2.14	%	—			—		9/29/06	10/30/36	3 month EURIBOR + 2.05
	Trust CS 2006-4 (3)	16,470			2.18	%	—			—		12/5/06	1/30/37	3 month LIBOR + 1.95
	Trust CS 2006-5 (3)	6,650			2.18	%	—			—		12/19/06	1/30/37	3 month LIBOR + 1.95
	Trust CS 2007-2 (3)	39,177			2.18	%	—			—		6/13/07	7/30/37	3 month LIBOR + 1.95
	Gross subordinated debentures	542,976					135,055
	Unamortized discount (5)	(109,393		)			(2,410		)
	Net subordinated debentures	$	433,583				$	132,645
	___________________
	-1	As of December 31, 2014.
	-2	As of January 28, 2014.
	-3	Acquired in the CapitalSource Inc. merger.
	-4	Denomination is in Euros with a value of €25.8 million.
	-5	Amount represents the fair value adjustment on trust preferred securities assumed in the CapitalSource Inc. and FCAL acquisitions.
	Interest payments made by the Company on subordinated debentures are considered dividend payments under the Board of Governors of the Federal Reserve System (“FRB”) regulations. Bank holding companies, such as PacWest, are required to notify the FRB prior to declaring and paying a dividend to stockholders during any period in which quarterly and/or cumulative twelve‑month net earnings are insufficient to fund the dividend amount, among other requirements.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES
	Lending Commitments
	The Bank is a party to financial instruments with off‑balance sheet risk in the normal course of business to meet the financing needs of its customers. These financial instruments include commitments to extend credit, standby letters of credit, and commitments to purchase equipment being acquired for lease to others. Those instruments involve, to varying degrees, elements of credit risk in excess of the amount recognized in the consolidated balance sheets. The contract or notional amounts of those instruments reflect the extent of involvement the Company has in particular classes of financial instruments.
	The following table presents a summary of the financial instruments described above as of the dates indicated:
		31-Dec-14		31-Dec-13
		(In thousands)
	Loan commitments to extend credit	$	1,921,067	$	1,001,740
	Standby letters of credit	88,495		39,200
	Commitments to purchase equipment being acquired for lease to others	12,839		8,475
		$	2,022,401	$	1,049,415
	Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since many of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements.
	Standby letters of credit are conditional commitments issued by the Company to guarantee the performance of a customer to a third party. We provide standby letters of credit in conjunction with several of our lending arrangements and property lease obligations. Most guarantees expire within one year from the date of issuance. If a borrower defaults on its commitments subject to any letter of credit issued under these arrangements, we would be required to meet the borrower's financial obligation but would seek repayment of that financial obligation from the borrower. In some cases, borrowers have pledged cash and investment securities as collateral with us under these arrangements.
	In addition, the Company has investments in low income housing project partnerships, which provide the Company income tax credits, and in a few small business investment companies. The investments call for capital contributions up to an amount specified in the partnership agreements. As of December 31, 2014 and 2013, the Company had commitments to contribute capital to these entities totaling $11.0 million. In connection with equity investments added from the CapitalSource Inc. merger, we have committed to contribute up to an additional $2.9 million to 11 private equity funds.
	Legal Matters
	In the ordinary course of our business, we are party to various legal actions, which we believe are incidental to the operation of our business. The outcome of such legal actions and the timing of ultimate resolution are inherently difficult to predict. In the opinion of management, based upon information currently available to us, any resulting liability, in addition to amounts already accrued, would not have a material adverse effect on the Company’s financial statements or operations.

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE MEASUREMENTS
	ASC Topic 820, “Fair Value Measurement,” defines fair value, establishes a framework for measuring fair value including a three‑level valuation hierarchy, and expands disclosures about fair value measurements. Fair value is defined as the exchange 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 reflecting assumptions that a market participant would use when pricing an asset or liability. The hierarchy uses three levels of inputs to measure the fair value of assets and liabilities as follows:
	•	Level 1: Quoted prices (unadjusted) for identical assets or liabilities in active markets.
	•	Level 2: Observable inputs other than Level 1, including quoted prices for similar assets and liabilities in active markets, quoted prices in less active markets, or other observable inputs that can be corroborated by observable market data, either directly or indirectly, for substantially the full term of the financial instrument. This category generally includes government agency and government‑sponsored enterprise securities.
	•	Level 3: Inputs to a valuation methodology that are unobservable, supported by little or no market activity, and significant to the fair value measurement. These valuation methodologies generally include pricing models, discounted cash flow models, or a determination of fair value that requires significant management judgment or estimation. This category also includes observable inputs from a pricing service not corroborated by observable market data, and includes our covered private label CMOs.
	We use fair value to measure certain assets and liabilities on a recurring basis, primarily securities available‑for‑sale and derivatives. For assets measured at the lower of cost or fair value, the fair value measurement criteria may or may not be met during a reporting period and such measurements are therefore considered “nonrecurring” for purposes of disclosing our fair value measurements. Fair value is used on a nonrecurring basis to adjust carrying values for impaired loans and other real estate owned and also to record impairment on certain assets, such as goodwill, core deposit intangibles, and other long‑lived assets.
	The following tables presents information on the assets measured and recorded at fair value on a recurring basis as of the dates indicated:
		Fair Value Measurements as of
		December 31, 2014
	Measured on a Recurring Basis:	Total				Level 1			Level 2			Level 3
		(In thousands)
	Securities available‑for‑sale:
	Government agency and government‑sponsored enterprise
	pass-through securities	$	535,672			$	—		$	535,672		$	—
	Government agency and government‑sponsored enterprise
	collateralized mortgage obligations	277,946				—			277,946			—
	Covered private label CMOs	33,947				—			—			33,947
	Other private label CMOs	10,914				—			10,914			—
	Municipal securities	536,116				—			536,116			—
	Corporate debt securities	110,109				—			110,109			—
	Government‑sponsored enterprise debt securities	36,757				—			36,757			—
	Other securities	25,716				519			25,197			—
	Total securities available-for-sale	1,567,177				519			1,532,711			33,947
	Derivative assets	5,234				—			5,234			—
	Total recurring assets	$	1,572,411			$	519		$	1,537,945		$	33,947
	Derivative liabilities	$	118			$	—		$	118		$	—
		Fair Value Measurements as of
		December 31, 2013
	Measured on a Recurring Basis:	Total				Level 1			Level 2			Level 3
		(In thousands)
	Securities available‑for‑sale:
	Government agency and government‑sponsored enterprise
	pass-through securities	$	707,188			$	—		$	707,188		$	—
	Government agency and government‑sponsored enterprise
	collateralized mortgage obligations	192,873				—			192,873			—
	Covered private label CMOs	37,904				—			—			37,904
	Municipal securities	436,658				—			436,658			—
	Corporate debt securities	82,707				—			82,707			—
	Government‑sponsored enterprise debt securities	9,872				—			9,872			—
	Other securities	27,543				507			27,036			—
	Total recurring assets	$	1,494,745			$	507		$	1,456,334		$	37,904
	There were no transfers of assets either between Level 1 and Level 2 nor in or out of Level 3 of the fair value hierarchy for assets measured on a recurring basis during the year ended December 31, 2014.
	The following table presents information about quantitative inputs and assumptions used to determine the fair values provided by our third party pricing service for our Level 3 covered private label CMOs measured at fair value on a recurring basis as of December 31, 2014:
			Covered Private Label CMOs
	Unobservable Inputs:		Range of Inputs		Weighted Average Input
	Voluntary annual prepayment speeds		0% - 36.4%		6.30%
	Annual default rates		0% - 38.0%		2.30%
	Loss severity rates		0% - 68.6%		24.00%
	Discount rates		0.2% - 6.7%		4.90%
	The following table summarizes activity for assets measured at fair value on a recurring basis that are categorized as Level 3 for the years indicated:
		Year Ended December 31,
		2014				2013			2012
	Covered Private Label CMOs:	(In thousands)
	Balance, beginning of year	$	37,904			$	44,684		$	45,149
	Total realized in earnings(1)	1,627				1,938			340
	Total unrealized gain (loss) in comprehensive income	(344		)		(1,204		)	4,883
	Net settlements	(5,240		)		(7,514		)	(5,688		)
	Balance, end of year	$	33,947			$	37,904		$	44,684
	_________________________
	-1	Includes other-than-temporary impairment of $1.1 million for 2012.
	The following tables present assets measured at fair value on a non‑recurring basis as of the dates indicated:
		Fair Value Measurement as of
		December 31, 2014
		Total				Level 1			Level 2			Level 3
Measured on a Non‑Recurring Basis:	(In thousands)
Impaired Non‑PCI loans	$	42,693			$	—		$	2,366		$	40,327
Other real estate owned	24,015				—			18,400			5,615
Investments carried at cost	566				—			—			566
Total non-recurring	$	67,274			$	—		$	20,766		$	46,508
	Fair Value Measurement as of
	December 31, 2013
	Total				Level 1			Level 2			Level 3
Measured on a Non‑Recurring Basis:	(In thousands)
Impaired Non‑PCI loans	$	40,886			$	—		$	2,051		$	38,835
Other real estate owned	10,877				—			8,784			2,093
Total non-recurring	$	51,763			$	—		$	10,835		$	40,928
The following table presents gains and (losses) recognized on assets measured on a nonrecurring basis for the years indicated:
	Year Ended December 31,
	2014				2013			2012
Gain (Loss) on Assets Measured on a Non‑Recurring Basis:	(In thousands)
Impaired Non‑PCI loans	$	(7,006	)		$	(1,206	)	$	(5,582	)
Other real estate owned	(6,737		)		(1,045		)	(3,920		)
Investments carried at cost	(141		)		—			—
Total net loss	$	(13,884	)		$	(2,251	)	$	(9,502	)
The following table presents the valuation methodology and unobservable inputs for Level 3 assets measured at fair value on a nonrecurring basis as of December 31, 2014:
Asset	Fair Value				Valuation Technique		Unobservable Inputs	Range		Weighted
	(In thousands)									Average
Impaired Non-PCI loans	$	36,149			Discounted cash flows		Discount rates	0% - 12.17%		5.92%
	4,178				Appraisals		No discounts
Other real estate owned	5,615				Appraisals		Discount, including selling costs	24% - 38%		35%
Investments carried at cost	566				Market and Income Approach		Illiquidity Discount	75%		75%
Total non-recurring Level 3	$	46,508
ASC Topic 825, “Financial Instruments,” requires disclosure of the estimated fair value of certain financial instruments and the methods and significant assumptions used to estimate such fair values. Additionally, certain financial instruments and all nonfinancial instruments are excluded from the applicable disclosure requirements.
The following tables present a summary of the carrying values and estimated fair values of certain financial instruments as of the dates indicated:
	31-Dec-14
	Carrying or				Estimated Fair Value
	Contract
	Amount				Total			Level 1			Level 2		Level 3
	(In thousands)
Financial Assets:
Cash and due from banks	$	164,757			$	164,757		$	164,757		$	—	$	—
Interest‑earning deposits in financial institutions	148,469				148,469			148,469			—		—
Securities available‑for‑sale	1,567,177				1,567,177			519			1,532,711		33,947
Investment in FHLB stock	40,609				40,609			—			40,609		—
Investments carried at cost	3,691				3,691			—			—		3,691
Investments accounted for under the equity method	21,461				21,700			—			—		21,700
Loans and leases, net	11,797,977				11,757,951			—			2,366		11,755,585
Derivative assets	5,234				5,234			—			5,234		—
Financial Liabilities:
Deposits:
Demand, money market, interest checking, and savings deposits	6,256,190				6,256,190			—			6,256,190		—
Time deposits	5,498,938				5,202,464			—			5,202,464		—
Borrowings	383,402				383,539			380,000			3,539		—
Subordinated debentures	433,583				417,657			—			417,657		—
Derivative liabilities	118				118			—			118		—
	31-Dec-13
	Carrying or				Estimated Fair Value
	Contract
	Amount				Total			Level 1			Level 2		Level 3
	(In thousands)
Financial Assets:
Cash and due from banks	$	96,424			$	96,424		$	96,424		$	—	$	—
Interest‑earning deposits in financial institutions	50,998				50,998			50,998			—		—
Securities available‑for‑sale	1,494,745				1,494,745			507			1,456,334		37,904
Investment in FHLB stock	27,939				27,939			—			27,939		—
Loans and leases, net	4,230,318				4,231,078			—			2,051		4,229,027
Financial Liabilities:
Deposits:
Demand, money market, interest checking, and savings deposits	4,616,616				4,616,616			—			4,616,616		—
Time deposits	664,371				665,148			—			665,148		—
Borrowings	113,726				113,726			106,600			7,126		—
Subordinated debentures	132,645				132,498			—			132,498		—
The following is a description of the valuation methodologies used to measure our assets recorded at fair value (under ASC Topic 820, “Fair Value Measurement”) and for estimating fair value for financial instruments not recorded at fair value (under ASC Topic 825).
Cash and due from banks. The carrying amount is assumed to be the fair value because of the liquidity of these instruments.
Interest‑earning deposits in financial institutions. The carrying amount is assumed to be the fair value given the short‑term nature of these deposits.
Securities available‑for‑sale. Securities available‑for‑sale are measured and carried at fair value on a recurring basis. Unrealized gains and losses on available‑for‑sale securities are reported as a component of “Accumulated other comprehensive income” in the consolidated balance sheets. See Note 5, Investment Securities, for further information on unrealized gains and losses on securities available‑for‑sale.
Fair value for securities categorized as Level 1, which are publicly traded securities, are based on readily available quoted prices. In determining the fair value of the securities categorized as Level 2, we obtain a report from a nationally recognized broker‑dealer detailing the fair value of each investment security we hold as of each reporting date. The broker‑dealer uses observable market information to value our securities, with the primary source being a nationally recognized pricing service. We review the market prices provided by the broker‑dealer for our securities for reasonableness based on our understanding of the marketplace and we consider any credit issues related to the securities. As we have not made any adjustments to the market quotes provided to us and they are based on observable market data, they have been categorized as Level 2 within the fair value hierarchy.
Our covered private label CMOs are categorized as Level 3 due in part to the inactive market for such securities. There is a wide range of prices quoted for private label CMOs among independent third party pricing services and this range reflects the significant judgment being exercised over the assumptions and variables that determine the pricing of such securities. We consider this subjectivity to be a significant unobservable input and have concluded that the covered private label CMOs should be categorized as a Level 3 measured asset. Our fair value estimate was based on prices provided to us by a nationally recognized pricing service which we also use to determine the fair value of the majority of our securities portfolio. We determined the reasonableness of the fair values by reviewing assumptions at the individual security level about prepayment, default expectations, estimated severity loss factors, and discount rates, all of which are not directly observable in the market. Significant changes in default expectations, severity loss factors, or discount rates, which occur all together or in isolation, would result in different fair value measurements.
FHLB stock. Investments in FHLB stock are recorded at cost and measured for impairment quarterly. Ownership of FHLB stock is restricted to member banks and the securities do not have a readily determinable market value. Purchases and sales of these securities are at par value with the issuer. The fair value of investments in FHLB stock is equal to the carrying amount.
Non-PCI loans and leases. As Non-PCI loans and leases are not measured at fair value, the following discussion relates to estimating the fair value disclosures under ASC Topic 825. Fair values are estimated for portfolios of loans and leases with similar financial characteristics. Loans are segregated by type and further segmented into fixed and adjustable rate interest terms by credit risk categories. The fair value estimates do not take into consideration the value of the loan portfolio in the event the loans are sold outside the parameters of normal operating activities. The fair value of performing fixed-rate loans is estimating by discounting scheduled cash flows through the estimated maturity using estimated market prepayment speeds. The fair value of equipment leases is estimated by discounting scheduled lease and expected lease residual cash flows over their remaining term. The estimated market discount rates used for performing fixed-rate loans and equipment leases are current market rates for instruments with similar risk and similar terms. The fair value of performing adjustable-rate loans is estimated by discounting scheduled cash flows through the next repricing date. As these loans reprice frequently at market rates and the credit risk is not considered to be greater than normal, the market value is typically close to the carrying amount of these loans. These methods and assumptions are not based on the exit price concept of fair value.
Impaired Non‑PCI loans. Nonaccrual loans and performing restructured loans are considered impaired for reporting purposes and are measured and recorded at fair value on a non‑recurring basis. Nonaccrual Non‑PCI loans with an unpaid principal balance over $250,000 and all performing restructured loans are reviewed individually for the amount of impairment, if any. Nonaccrual Non‑PCI loans with an unpaid principal balance less than $250,000 are not individually assessed for impairment but are instead reserved for under our general reserve component.
To the extent a loan is collateral dependent, we measure such impaired loan based on the estimated fair value of the underlying collateral. The fair value of each loan’s collateral is generally based on estimated market prices from an independently prepared appraisal, which is then adjusted for the cost related to liquidating such collateral; such valuation inputs result in a nonrecurring fair value measurement that is categorized as a Level 2 measurement. The Level 2 measurement is based on appraisals obtained within the last 12 months and for which a charge‑off was recognized or a change in the specific valuation allowance was made during the year ended December 31, 2014.
When adjustments are made to an appraised value to reflect various factors such as the age of the appraisal or known changes in the market or the collateral, such valuation inputs are considered unobservable and the fair value measurement is categorized as a Level 3 measurement. The impaired loans categorized as Level 3 also include unsecured loans and other secured loans whose fair values are based significantly on unobservable inputs such as the strength of a guarantor, including an SBA government guarantee, cash flows discounted at the effective loan rate, and management’s judgment.
The impaired Non‑PCI loan balances shown above as measured on a non-recurring basis represent those nonaccrual and restructured loans for which impairment was recognized during the year ended December 31, 2014. The amounts shown as net losses include the impairment recognized during the year ended December 31, 2014, for the loan balances shown. Of the $83.6 million of nonaccrual Non-PCI loans at December 31, 2014, $4.4 million were written down to their collateral fair values through charge‑offs during the year ended December 31, 2014.
Investments that do not have readily determinable fair values. Other investments accounted for under the cost or equity methods of accounting are carried at fair value on a nonrecurring basis to the extent that they are determined to be other-than-temporarily impaired during the period. As there is rarely an observable price or market for such investments, we determine fair value using internally developed models. Our models utilize industry valuation benchmarks, such as multiples of net revenue or EBITA, to determine a value for the underlying enterprise. We may also reduce the value determined by the model due to illiquidity or other investee-specific characteristics which may affect the fair value. Significant decreases to these valuation benchmarks would result in significant decreases in the estimated fair values. We reduce this value by the value of debt outstanding to arrive at an estimated equity value of the enterprise. When an external event such as a purchase transaction, public offering or subsequent equity sale occurs, the pricing indicated by the external event is used to corroborate our internal valuation. Fair value measurements related to these investments are typically classified within Level 3 of the fair value hierarchy.
Other real estate owned ("OREO"). The fair value of foreclosed real estate is generally based on the lower of estimated market prices from independently prepared current appraisals or negotiated sales prices with potential buyers, less estimated costs to sell; such valuation inputs result in a fair value measurement that is categorized as a Level 2 measurement on a nonrecurring basis. As a matter of policy, appraisals are required annually and may be updated more frequently as circumstances require in the opinion of management. The Level 2 measurement for OREO is based on appraisals obtained within the last 12 months and for which a write‑down was recognized during the year ended December 31, 2014.
When a current appraised value is not available or management determines the fair value of the collateral is further impaired below the appraised value as a result of known changes in the market or the collateral and there is no observable market price, such valuation inputs result in a fair value measurement that is categorized as a Level 3 measurement. To the extent a negotiated sales price or reduced listing price represents a significant discount to an observable market price, such valuation input would result in a fair value measurement that is also considered a Level 3 measurement. The OREO losses disclosed are write‑downs based on either a recent appraisal obtained after foreclosure or an accepted purchase offer by an independent third party received after foreclosure.
Deposits. Deposits are carried at historical cost. The fair value of deposits with no stated maturity, such as noninterest‑bearing demand deposits, interest checking, money market, and savings accounts, is equal to the amount payable on demand as of the balance sheet date and considered Level 2. The fair value of time deposits is based on the discounted value of contractual cash flows and considered Level 2. The discount rate is estimated using the rates currently offered for deposits of similar remaining maturities. No value has been separately assigned to the Company’s long‑term relationships with its deposit customers, such as a core deposit intangible.
Borrowings. Borrowings include overnight FHLB advances and other fixed‑rate term borrowings. Borrowings are carried at amortized cost. The fair value of overnight FHLB advances is equal to the carrying value and considered Level 1. The fair value of fixed‑rate borrowings is calculated by discounting scheduled cash flows through the estimated maturity dates or call dates, if applicable, using estimated market discount rates that reflect current rates offered for borrowings with similar remaining maturities and characteristics and are considered Level 2.
Subordinated debentures. Subordinated debentures are carried at amortized cost. The fair value of subordinated debentures with variable rates is determined using a market discount rate on the expected cash flows.
Derivative assets and liabilities. Derivatives are carried at fair value on a recurring basis and primarily relate to forward exchange contracts which we enter into to manage foreign exchange risk. Our derivatives are principally traded in over-the-counter markets where quoted market prices are not readily available. Instead, the fair value of derivatives is estimated using market observable inputs such as foreign exchange forward rates, interest rate yield curves, volatilities and basis spreads. We also consider counterparty credit risk in valuing our derivatives. We typically classify our derivatives in Level 2 of the fair value hierarchy.
Commitments to extend credit. The majority of our commitments to extend credit carry current market interest rates if converted to loans. Because these commitments are generally unassignable by either the borrower or us, they only have value to the borrower and us. The estimated fair value approximates the recorded deferred fee amounts and is excluded from the table above because it is not material.
Limitations
Fair value estimates are made at a specific point in time and are based on relevant market information and information about the financial instrument. These estimates do not reflect income taxes or any premium or discount that could result from offering for sale at one time the Company’s entire holdings of a particular financial instrument. Because no market exists for a portion of the Company’s financial instruments, fair value estimates are based on what management believes to be conservative judgments regarding expected future cash flows, current economic conditions, risk characteristics of various financial instruments, and other factors. These estimated fair values are subjective in nature and involve uncertainties and matters of significant judgment and therefore cannot be determined with precision. Changes in assumptions could significantly affect the estimates. Since the fair values have been estimated as of December 31, 2014, the amounts that will actually be realized or paid at settlement or maturity of the instruments could be significantly different.

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES
	The following table presents the components of income tax expense for the years indicated:
		December 31,
		2014			2013			2012
		(In thousands)
	Current Income Tax Expense:
	Federal	$	(11,459	)	$	(29,591	)	$	(24,177	)
	State	(10,823		)	(7,667		)	(1,825		)
	Total current income tax expense	(22,282		)	(37,258		)	(26,002		)
	Deferred Income Tax (Expense) Benefit:
	Federal	(70,662		)	9,099			(2,550		)
	State	(19,795		)	(1,586		)	(8,143		)
	Total deferred income tax (expense) benefit	(90,457		)	7,513			(10,693		)
	Total income tax expense	$	(112,739	)	$	(29,745	)	$	(36,695	)
	The following table presents a reconciliation of the recorded income tax expense to the amount of taxes computed by applying the applicable federal statutory income tax rate of 35% to earnings or loss before income taxes for the years indicated:
		December 31,
		2014			2013			2012
		(In thousands)
	Computed expected income tax expense at federal statutory rate	$	(98,575	)	$	(26,201	)	$	(32,724	)
	State tax expense, net of federal tax benefit	(15,689		)	(6,014		)	(6,479		)
	Tax‑exempt interest benefit	4,472			3,979			1,847
	Increase in cash surrender value of life insurance	739			407			442
	Tax credits	3,567			2,480			1,313
	Nondeductible employee compensation	(6,792		)	(4,730		)	(322		)
	Nondeductible acquisition‑related expense	(2,994		)	(1,196		)	(532		)
	Acquisition‑related securities gain	—			1,828			—
	Other, net	2,533			(298		)	(240		)
	Recorded income tax expense	$	(112,739	)	$	(29,745	)	$	(36,695	)
	The Company had net income taxes receivable of $18.3 million and $39.6 million million at December 31, 2014 and 2013, included in other assets on its consolidated balance sheets.
	At the time of the merger with CapitalSource Inc., a valuation allowance of $130.7 million was established against the acquired deferred tax assets (“DTA”). Periodic reviews of the carrying amount of DTA are made to determine if a valuation allowance is necessary. A valuation allowance is required, based on available evidence, when it is more likely than not that all or a portion of a DTA will not be realized due to the inability to generate sufficient taxable income in the period and/or of the character necessary to utilize the benefit of the DTA. All available evidence, both positive and negative, that may affect the realizability of the DTA are identified and considered in determining the appropriate amount of the valuation allowance. As of December 31, 2014, the Company had a valuation allowance of $130.3 million. It is more likely than not that these deferred tax assets subject to a valuation allowance will not be realized primarily due to their character and/or the expiration of the carryforward periods.
	We have net operating loss and tax credit carryforwards for federal and state income tax purposes that can be utilized to offset future taxable income. If we were to undergo a change in ownership of more than 50% of our capital stock over a three-year period as measured under Section 382 of the Internal Revenue Code (“the Code”), our ability to utilize our net operating loss forwards and other tax attributes after the ownership change generally would be limited. The annual limit would equal the product of the applicable long term tax exempt rate and the value of the relevant taxable entity’s capital stock immediately before the ownership change. These change of ownership rules generally focus on ownership changes involving stockholders owning directly or indirectly 5% or more (the “5-Percent Shareholders”) of a company’s outstanding stock, including certain public groups of stockholders as set forth under Section 382, and those arising from new stock issuances and other equity transactions, which may limit our willingness and ability to issue new equity. The determination of whether an ownership change occurs is complex and not entirely within our control. No assurance can be given as to whether we have undergone, or in the future will undergo, an ownership change under Section 382 of the Internal Revenue Code.
	In April 2014, the Board of Directors adopted a tax benefit preservation plan ("the Tax Plan") which was designed to preserve the net operating loss carryforwards and other tax attributes for the Company. The Tax Plan is intended to discourage persons from becoming 5-Percent Shareholders and existing 5-Percent Shareholders from increasing their beneficial ownership of share.
	We had available at December 31, 2014, approximately $446.4 million of unused federal net operating loss carryforwards that may be applied against future taxable income. If not used, these carryforwards will begin to expire in 2030 and fully expire in 2031. We had available at December 31, 2014, approximately $936.3 million of unused state net operating loss carryforwards that may be applied against future taxable income. The state net operating loss carryforwards will expire in varying amounts beginning in 2015 through 2033.
	As of December 31, 2014, for federal tax purposes, we had capital loss carryforwards of $135.8 million, of which $132.4 million was acquired as a result of the merger with CapitalSource Inc. If not used, these carryforwards will begin to expire in 2015 and will fully expire in 2019.
	As of December 31, 2014, for federal tax purposes, we had foreign tax credit carryforwards of $28.6 million, all of which was acquired as a result of the merger with CapitalSource Inc. The foreign tax credit carryforwards are available to offset future federal taxable income. If not used, these carryforwards will begin to expire in 2016 and fully expire in 2021. We also had Low Income Housing Tax Credit carryforwards of $3.3 million, which if not used, will expire in 2034.
	The following table presents the tax effects of temporary differences that give rise to significant portions of deferred tax assets and deferred tax liabilities as of the dates indicated:
		December 31,
		2014			2013
		(In thousands)
	Deferred Tax Assets:
	Book allowance for loan losses in excess of tax specific charge-offs	$	100,981		$	45,840
	Interest on nonaccrual loans	7,394			444
	Deferred compensation	4,585			4,541
	Premises and equipment, principally due to differences in depreciation	5,359			3,643
	Foreclosed assets valuation allowance	7,353			9,784
	Assets acquired in FDIC‑assisted acquisition	10,217			16,375
	State tax benefit	5,009			2,368
	Net operating losses	207,575			197
	Capital loss carryforwards	57,494			—
	Accrued liabilities	36,115			16,629
	Other	6,254			8,084
	Equity Investments	8,666			568
	Goodwill	44,372			6,595
	Deferred loan fees and costs	—			378
	Tax credits	32,183			—
	Unrealized loss on securities available‑for‑sale	—			2,424
	Gross deferred tax assets	533,557			117,870
	Valuation Allowance	(130,282		)	—
	Deferred tax assets, net of valuation allowance	403,275			117,870
	Deferred Tax Liabilities:
	Core deposit and customer relationship intangibles	3,978			6,022
	Deferred loan fees and costs	17,594			—
	Unrealized gain on securities available‑for‑sale	17,926			—
	FHLB stock	2,820			7,123
Subordinated debentures	40,369			1,003
Operating Leases	34,136			—
Unrealized income from FDIC‑assisted acquisition	2,041			24,086
Gross deferred tax liabilities	118,864			38,234
Total net deferred tax asset	$	284,411		$	79,636
Based upon our taxpaying history and estimates of taxable income over the years in which the items giving rise to the deferred tax assets are deductible, management believes it is more likely than not the Company will realize the benefits of these deductible differences.
We had no unrecognized net tax benefit positions at December 31, 2013 and 2012. The increase of unrecognized tax benefits related to the merger with CapitalSource Inc. was $18.7 million. The schedule below details the activities during 2014.
	Unrecognized
	Tax Benefits
	(In thousands)
Balance, December 31, 2013	$	—
Increase related to CapitalSource Inc. merger	18,724
Increase based on tax positions related to prior years	2,371
Reductions related to settlements	(293		)
Reductions for tax positions as a result of a lapse of the applicable statute of limitations	(301		)
Balance, December 31, 2014	$	20,501
As of December 31, 2014, our unrecognized tax benefit that may affect the effective tax rate was $2.4 million. Due to the potential for the resolution of federal and state examinations and the expiration of various statutes of limitations, it is reasonably possible that our gross unrecognized tax benefits may decrease within the next twelve months by as much as $2.0 million.
We recognize accrued interest and penalties related to unrecognized tax benefits as a component of income taxes. For the year ended December 31, 2014 we recognized $0.2 million in interest expense and penalties. We had $3.3 million ($3.1 million is related to the merger) accrued for the payment of interest and penalties as of December 31, 2014. The amount of interest and penalties accrued and recognized for the years ended December 31, 2013 and 2012 was minimal and immaterial to our financial results.
We file income tax returns with the United States and various states, local and foreign jurisdictions and generally remain subject to examinations by these tax jurisdictions for tax years 2006 through 2013. We are currently under examination by the United States for tax years 2008 through 2012 and certain state jurisdictions for tax years 2006 through 2012.

Earnings_per_share

Earnings per share	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Earnings Per Share	EARNINGS PER SHARE
	The following table presents the computation of basic and diluted net earnings per share for the years indicated:
		Year Ended December 31,
		2014			2013			2012
		(Dollars in thousands, except per share data)
	Basic earnings per share:
	Net earnings from continuing operations	$	170,468		$	45,477		$	56,801
	Less: earnings allocated to unvested restricted stock(1)	(1,959		)	(1,096		)	(1,845		)
	Net earnings from continuing operations allocated to common shares	168,509			44,381			54,956
	Net (loss) earnings from discontinued operations allocated to common shares	(1,545		)	(348		)	—
	Net earnings allocated to common shares	$	166,964		$	44,033		$	54,956
	Weighted-average basic shares and unvested restricted stock outstanding	87,871			42,506			37,370
	Less: weighted-average unvested restricted stock outstanding	(1,018		)	(1,683		)	(1,685		)
	Weighted-average basic shares outstanding	86,853			40,823			35,685
	Basic earnings per share:
	Net earnings from continuing operations	$	1.94		$	1.09		$	1.54
	Net loss from discontinued operations	(0.02		)	(0.01		)	—
	Net earnings	$	1.92		$	1.08		$	1.54
	Diluted earnings per share:
	Net earnings from continuing operations allocated to common shares	$	168,509		$	44,381		$	54,956
	Net (loss) earnings from discontinued operations allocated to common shares	(1,545		)	(348		)	—
	Net earnings allocated to common shares	$	166,964		$	44,033		$	54,956
	Weighted-average basic shares outstanding	86,853			40,823			35,685
	Diluted earnings per share:
	Net earnings from continuing operations	$	1.94		$	1.09		$	1.54
	Net loss from discontinued operations	(0.02		)	(0.01		)	—
	Net earnings	$	1.92		$	1.08		$	1.54
	________________________
	-1	Represents cash dividends paid to holders of unvested restricted stock, net of estimated forfeitures, plus undistributed earnings amounts available to holders of unvested restricted stock, if any.

Stock_Based_Compensation_Plan

Stock Based Compensation Plan	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Disclosure of Compensation Related Costs, Share-based Payments [Text Block]	NOTE 17.  STOCK BASED COMPENSATION PLANS
	The Company’s 2003 Stock Incentive Plan, or the 2003 Plan, permits stock-based compensation awards to officers, directors, key employees and consultants. As of December 31, 2014, the 2003 Plan authorized grants of stock‑based compensation instruments to purchase or issue up to 19,686,565 shares of Company common stock, subject to adjustments provided by the 2003 Plan. The authorized amount includes 10,686,565 shares that were added to the 2003 Plan as a result of the CapitalSource Inc. merger. Such shares were available for grant under the former CapitalSource Inc. Equity Incentive Plan and remain available for: (a) former employees of CapitalSource Bank who remain employed with the Company, and (b) newly hired employees of the Company. As of December 31, 2014, there were 13,531,719 shares available for grant under the 2003 Plan, of which 10,107,039 shares related to those added from the CapitalSource Inc. merger.
	Restricted Stock
	The following table presents a summary of restricted stock transactions for the years indicated:
		Number of		Weighted Average
		Shares		Grant Date Fair Value
				(Per Share)
	Unvested restricted stock, December 31, 2011	1,675,730		$	30.53
	Granted	226,400		23.77
	Shares issued by the Company upon vesting	(195,871	)	21.69
	Forfeited	(7,978	)	22.31
	Unvested restricted stock, December 31, 2012	1,698,281		30.68
	Granted	673,900		29.06
	Shares issued by the Company upon vesting	(819,461	)	24.84
	Forfeited	(336,196	)	48.92
	Unvested restricted stock, December 31, 2013	1,216,524		28.69
	Granted	1,129,805		40.37
	Shares issued by the Company upon vesting	(1,183,024	)	28.53
	Forfeited	(54,800	)	38.97
	Unvested restricted stock, December 31, 2014	1,108,505		$	40.37
	At December 31, 2014, there were 1,108,505 shares of unvested time‑based restricted common stock outstanding. The awarded shares of time‑based restricted common stock vest over a service period of three to four years from the date of the grant. The time-based restricted common stock also vests immediately upon a change in control of the Company, as defined in the 2003 Plan, or upon death of the employee. In April 2014, upon closing of the CapitalSource Inc. merger, 1,013,377 of awarded shares of restricted common stock vested due to the triggering of the change of control provision contained within the 2003 Plan. We recorded a $26.1 million charge to earnings for the vesting of such shares. Such amount is included in acquisition, integration and reorganization costs on the accompanying consolidated statements of earnings in the second quarter of 2014. The vesting date fair values of restricted stock awards that vested during 2014, 2013 and 2012 were $53.4 million, $30.9 million and $4.5 million.
	Compensation expense related to time‑based restricted stock awards is based on the fair value of the underlying stock on the award date and is recognized over the vesting period using the straight‑line method. Restricted stock amortization totaled $9.8 million (excluding accelerated vesting of restricted stock of $26.1 million), $8.5 million (excluding accelerated vesting of restricted stock of $12.4 million), and $5.7 million for the years ended December 31, 2014, 2013 and 2012. Such amounts are included in compensation expense on the accompanying consolidated statements of earnings. The income tax benefit recognized in the consolidated statements of earnings related to this expense was $3.9 million, $3.4 million and $2.2 million for the 2014, 2013 and 2012.
	The amount of unrecognized compensation expense related to all unvested restricted stock as of December 31, 2014 totaled $36.0 million. Such expense is expected to be recognized over a weighted average period of 1.6 years.
	The following table summarizes information about outstanding time-based restricted stock awards as of the date indicated:
		December 31, 2014
				Weighted				Weighted
				Average		Weighted		Average
		Number		Grant Date		Average		Remaining
		of Shares		Fair Value		Fair Value(1)		Contractual
		Outstanding		(Per Share)		(In thousands)		Life (Years)
	Time-based restricted stock granted in:
	2013	27,000		$	35.08	$	1,228	1.6
	2014	1,081,505		$	40.37	49,165		1.6
	Outstanding time-based restricted stock awards	1,108,505		$	40.37	$	50,393	1.6
	_________________________
	-1	Determined using the $45.46 closing price of PacWest common stock on December 31, 2014.

Benefit_Plans_Notes

Benefit Plans (Notes)	12 Months Ended
	Dec. 31, 2014
Benefit Plans [Abstract]
Benefits Plans	BENEFIT PLANS
	401(K) Plans
	The Company sponsors a defined contribution plan for the benefit of its employees. Participants are eligible to participate immediately as long as they are scheduled to work a minimum of 1,000 hours and are at least 21 years of age. Eligible participants may contribute up to 60% of their annual compensation, not to exceed the dollar limit imposed by the Internal Revenue Code. Employer contributions are determined annually by the Board of Directors in accordance with plan requirements and applicable tax code.
	Expense related to 401(k) matching contributions was $1.9 million, $1.3 million and $1.0 million for the years ended December 31, 2014, 2013, and 2012.

Stockholders_Equity_Notes

Stockholders' Equity (Notes)	12 Months Ended
	Dec. 31, 2014
Stockholders' Equity Disclosure [Abstract]
Stockholders' Equity	STOCKHOLDERS' EQUITY
	Treasury Shares
	As a Delaware corporation, the Company records treasury shares for shares surrendered to the Company resulting from statutory payroll tax obligations arising from the vesting of restricted stock. The Company purchased 493,890 treasury shares at a weighted average price of $45.16 per share, 351,640 treasury shares at a weighted average price of $38.50 per share and 63,681 treasury shares at a weighted average price of $23.17 per share for the years ended December 31, 2014, 2013, and 2012.
	Dividend Reinvestment
	We pay dividends on deferred shares and will continue to do so until April 2015.  The shares were deferred under a CapitalSource plan which was terminated, but due to 409A restrictions the shares remain deferred for a period of one year after termination.  Dividends paid on deferred shares are used to purchase our common stock.  During 2014, we paid approximately $115,000 on deferred shares which was used to purchase an additional 2,583 shares of our common stock.

Dividend_Availability_and_Regu

Dividend Availability and Regulatory Matters (Notes)	12 Months Ended
	Dec. 31, 2014
Dividend Availability and Regulatory Matters [Abstract]
Dividend Availability and Regulatory Matters	DIVIDEND AVAILABILITY AND REGULATORY MATTERS
	Holders of Company common stock may receive dividends declared by the Board of Directors out of funds legally available under state law governing the Company and certain federal laws and regulations governing the banking and financial services business. Our ability to pay dividends to our stockholders is subject to the restrictions set forth in Delaware General Corporation Law and certain covenants contained in our subordinated debentures and borrowing agreements. Notification to the FRB is also required prior to our declaring and paying dividends during any period in which our quarterly and/or cumulative twelve‑month net earnings are insufficient to fund the dividend amount, among other requirements. Should the FRB object to payment of dividends, we would not be able to make the payment until approval is received or we no longer need to provide notice under applicable regulations.
	It is possible, depending upon the financial condition of the Bank, and other factors, that the FRB, the FDIC or the California Department of Business Oversight, Division of Financial Institutions (“DBO”), could assert that payment of dividends or other payments is an unsafe or unsound practice. Pacific Western is subject to restrictions under certain federal and state laws and regulations governing banks which limit its ability to transfer funds to the holding company through intercompany loans, advances or cash dividends. Dividends paid by state banks such as Pacific Western are regulated by the DBO and FDIC under their general supervisory authority as it relates to a bank’s capital requirements. A state bank may declare a dividend without the approval of the DBO and FDIC as long as the total dividends declared in a calendar year do not exceed either the retained earnings or the total of net earnings for three previous fiscal years less any dividend paid during such period. During 2014, PacWest received $137.0 million in dividends from the Bank. For the foreseeable future, dividends from the Bank to PacWest will require DBO and FDIC approval.
	PacWest, as a bank holding company, is subject to regulation by the FRB under the Bank Holding Company Act of 1956, as amended. The Federal Deposit Insurance Corporation Improvement Act of 1991 required 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 and possibly additional discretionary actions by regulators that, if undertaken, could have a direct material effect on the Company’s consolidated financial statements. Under capital adequacy guidelines and the regulatory framework for prompt corrective action, the Company and the Bank must meet specific capital guidelines that involve quantitative measures of the Company’s 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.
	Quantitative measures established by regulation to ensure capital adequacy require the Company and the Bank to maintain minimum amounts and ratios of total and Tier I capital to risk‑weighted assets, and of Tier I capital to average assets (“leverage ratio”). Tier 1 capital includes common stockholders’ equity and trust preferred securities, less goodwill and certain other deductions (including a portion of servicing assets and the after‑tax unrealized net gains and losses on securities available‑for‑sale). Total risk‑based capital includes Tier 1 capital and other items such as subordinated debt and the allowance for credit losses. Both measures are stated as a percentage of risk‑weighted assets, which are measured based on their perceived credit risk and include certain off‑balance sheet exposures, such as unfunded loan commitments and letters of credit. The Company is also subject to a leverage ratio requirement, which is defined as Tier 1 capital as a percentage of average assets, adjusted for goodwill and other non‑qualifying intangible assets and other assets.
	Bank holding companies considered to be “adequately capitalized” are required to maintain a minimum total risk‑based capital ratio of 8.0%, a minimum Tier 1 risk‑based capital ratio of 4.0%, and a minimum leverage ratio of 4.0%. Bank holding companies considered to be “well capitalized” must maintain a minimum total risk‑based capital ratio of 10.0%, a minimum Tier 1 risk‑based capital ratio of 6.0%, and a minimum leverage ratio of 5.0%. As of December 31, 2014, the most recent notification date to the regulatory agencies, the Company and the Bank are each “well capitalized” under the regulatory framework for prompt corrective action. There are no conditions or events since that notification that management believes have changed the Company’s or any of the Bank’s categories.
	Management believes, as of December 31, 2014, that we have met all capital adequacy requirements to which we are subject.
	Regulatory capital requirements limit the amount of deferred tax assets that may be included when determining the amount of regulatory capital. Deferred tax asset amounts in excess of the calculated limit are deducted from regulatory capital. At December 31, 2014, such amount was $156.7 million for the Company and zero for the Bank. No assurance can be given that the regulatory capital deferred tax asset limitation will not increase in the future.
	The following table presents actual capital amounts and ratios for the Company and the Bank as of the dates indicated:
		Actual			Well Capitalized			Excess
					Minimum			Capital
					Requirement
		Amount	Ratio		Amount	Ratio		Amount
		(Dollars in thousands)
	31-Dec-14
	Tier I capital (to average assets):
	PacWest Bancorp Consolidated	1,722,870	12.34	%	698,109	5	%	1,024,761
	Pacific Western Bank	1,621,546	11.7	%	693,174	5	%	928,372
	Tier I capital (to risk‑weighted assets):
	PacWest Bancorp Consolidated	1,722,870	13.16	%	785,781	6	%	937,089
	Pacific Western Bank	1,621,546	12.46	%	780,834	6	%	840,712
	Total capital (to risk‑weighted assets):
	PacWest Bancorp Consolidated	2,104,984	16.07	%	1,309,635	10	%	795,349
	Pacific Western Bank	1,712,312	13.16	%	1,301,390	10	%	410,922
	31-Dec-13
	Tier I capital (to average assets):
	PacWest Bancorp Consolidated	718,800	11.22	%	320,405	5	%	398,395
	Pacific Western Bank	690,440	10.79	%	319,999	5	%	370,441
	Tier I capital (to risk‑weighted assets):
	PacWest Bancorp Consolidated	718,800	15.12	%	285,163	6	%	433,637
	Pacific Western Bank	690,440	14.54	%	284,825	6	%	405,615
	Total capital (to risk‑weighted assets):
	PacWest Bancorp Consolidated	778,582	16.38	%	475,271	10	%	303,311
	Pacific Western Bank	750,152	15.8	%	474,708	10	%	275,444
	The Company issued subordinated debentures to trusts that were established by us or entities that we have acquired, which, in turn, issued trust preferred securities. The amount of subordinated debentures totaled $433.6 million at December 31, 2014 and includes $300.4 million of debentures assumed in connection with the CapitalSource Inc. merger. The Company includes in Tier 1 capital an amount of trust preferred securities equal to no more than 25% of the sum of all core capital elements, which is generally defined as shareholders’ equity less goodwill, net of any related deferred income tax liability. At December 31, 2014, the amount of trust preferred securities included in Tier I capital was $131.0 million. The assumed CapitalSource Inc. trust preferred securities are ineligible for inclusion in Tier 1 capital but are included in Tier 2 capital. The $131.0 million of trust preferred securities are currently grandfathered as Tier 1 capital under the Dodd‑Frank Wall Street Reform and Consumer Protection Act. However, under new capital rules approved in July 2013 by the FRB and FDIC, as a result of the Company having exceeded $15 billion in consolidated total assets, beginning in 2015, only 25% of the Company’s $131.0 million of trust preferred securities currently outstanding will be included in Tier 1 capital, and in 2016, none of the Company’s trust preferred securities will be included in Tier 1 capital. Further, under such rules, trust preferred securities no longer included in the Company’s Tier 1 capital may be included as a component of Tier 2 capital on a permanent basis without phase‑out. If the $131.0 million of trust preferred securities are excluded from regulatory capital at December 31, 2014, we remain “well capitalized.”
	Interest payments made by the Company on subordinated debentures are considered dividend payments under the FRB regulations and subject to the same notification requirements for declaring and paying dividends on common stock.

Business_Segment

Business Segment	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Business Segments	BUSINESS SEGMENTS
	The Company’s reportable segments consist of “Community Banking," “National Lending,” and “Other.”
	As a result of the CapitalSource Inc. merger, Pacific Western Bank established the CapitalSource Division, which we also refer to as the National Lending segment. The CapitalSource Division, or National Lending segment, includes the lending operations gained through the CapitalSource Inc. merger, Pacific Western Equipment Finance, and the CapitalSource Business Finance Group (formerly BFI Business Finance and First Community Financial). We reorganized our asset-based lending and leasing operations when we established the CapitalSource Division. We combined BFI Business Finance and First Community Financial to form the CapitalSource Business Finance Group, and we sold Celtic Capital Corporation in July 2014.
	The CapitalSource Division lends throughout the United States, providing middle-market businesses asset-secured loans, equipment-secured loans, and cash flow loans and providing real estate investment firms real estate loans secured by various property types. The CapitalSource Division’s loan and lease origination efforts are conducted through offices located in Chevy Chase, Maryland; Los Angeles and San Jose, California; St. Louis, Missouri; Denver, Colorado; Chicago, Illinois; New York, New York; and Midvale, Utah.
	The Community Banking and National Lending segments include all of the operations of Pacific Western Bank. The Community Banking segment includes the operations of Pacific Western Bank, excluding the CapitalSource Division, and includes lending and deposit gathering activities conducted primarily through its California-based branch offices and the Bank’s treasury management function and corporate overhead. The Other segment consists of holding company operations which result in expenses principally for compensation, facilities, professional services, interest on subordinated debentures, and the non-bank subsidiary operations including interest income from a loan portfolio and related loan servicing expense.
	Transactions between segments consist primarily of borrowed funds and expense allocations for interest, deposit gathering, corporate overhead and credit loss provisions. Intersegment interest expense is allocated from the Community Banking segment to the National Lending segment based upon National Lending’s average interest-earning assets and operating leases, net of a capital allocation, and the Bank’s total cost of deposits. The Community Banking segment further allocates to the National Lending segment noninterest expense for deposit gathering and maintenance costs and the Bank’s corporate overhead. The provision for credit losses is allocated based on actual charge‑offs for the period as well as net portfolio growth and credit quality trends. All costs associated with investing the Bank’s excess liquidity and acquisition, integration and reorganization costs are housed in the Community Banking segment. Noninterest income and noninterest expense, including lending and loan servicing activity, directly attributable to a segment are assigned to such segment.
	The following tables present information regarding our business segments as of and for the years indicated:
		31-Dec-14
		Community			National						Consolidated
	Balance Sheet Data:	Banking			Lending			Other			Company
		(In thousands)
	Loans and leases, net of unearned income	$	3,401,129		$	8,455,849		$	25,454		$	11,882,432
	Allowance for loan and lease losses	(48,253		)	(36,202		)	—			(84,455		)
	Total loans and leases, net	$	3,352,876		$	8,419,647		$	25,454		$	11,797,977
	Goodwill(1)	$	326,078		$	1,394,401		$	—		$	1,720,479
	Core deposit and customer relationship intangibles, net	16,306			898			—			17,204
	Total assets	6,512,313			9,483,601			238,886			16,234,800
	Total deposits(2)	12,030,436			33,179			(308,487		)	11,755,128
	________________________
	-1	The increase in the goodwill for the Community Banking segment and National Lending segment during 2014 was due primarily to $1.5 billion from the CapitalSource merger.
	-2	The negative balance for total deposits in the “Other” segment represents the elimination of holding company cash held in deposit accounts at the Bank.
		31-Dec-13
		Community			National						Consolidated
	Balance Sheet Data:	Banking			Lending			Other			Company
		(In thousands)
	Loans and leases, net of unearned income	$	3,837,475		$	474,877		$	—		$	4,312,352
	Allowance for loan and lease losses	(75,498		)	(6,536		)	—			(82,034		)
	Total loans and leases, net	$	3,761,977		$	468,341		$	—		$	4,230,318
	Goodwill(1)	$	183,065		$	25,678		$	—		$	208,743
	Core deposit and customer relationship intangibles, net	15,331			1,917			—			17,248
	Total assets	6,004,067			519,675			9,621			6,533,363
	Total deposits(2)	5,302,822			—			(21,835		)	5,280,987
	________________________
	-1	The increase in the Community Banking segment's goodwill during 2013 was due primarily to $129.1 million from the FCAL acquisition.
	-2	The negative balance for total deposits in the “Other” segment represents the elimination of holding company cash held in deposit accounts at the Bank.
		Year Ended December 31, 2014
		Community			National						Consolidated
	Results of Operations:	Banking			Lending			Other			Company
		(In thousands)
	Interest income	$	279,671		$	422,677		$	2,427		$	704,775
	Interest expense	(27,598		)	(230		)	(14,570		)	(42,398		)
	Intersegment interest income (expense)	15,716			(15,716		)	—			—
	Net interest income (expense)	267,789			406,731			(12,143		)	662,377
	Negative provision (provision) for credit losses	21,311			(32,810		)	—			(11,499		)
	Gain on securities	4,841			—			—			4,841
	FDIC loss sharing expense	(31,730		)	—			—			(31,730		)
	Other noninterest income	25,168			34,215			9,693			69,076
	Total noninterest income	(1,721		)	34,215			9,693			42,187
	Foreclosed assets (expense) income, net	(5,685		)	(302		)	586			(5,401		)
	Intangible asset amortization	(5,745		)	(523		)	—			(6,268		)
	Acquisition, integration and reorganization costs	(89,888		)	(10,073		)	(1,055		)	(101,016		)
	Other noninterest expense	(198,921		)	(80,418		)	(16,720		)	(296,059		)
	Total noninterest expense	(300,239		)	(91,316		)	(17,189		)	(408,744		)
	Intersegment noninterest income (expense)	71,897			(71,897		)	—			—
	Total noninterest expense - adjusted	(228,342		)	(163,213		)	(17,189		)	(408,744		)
	Earnings from continuing operations before taxes	59,037			244,923			(19,639		)	284,321
	Income tax (expense) benefit	(27,370		)	(97,853		)	11,370			(113,853		)
	Net earnings (loss) from continuing operations	31,667			147,070			(8,269		)	170,468
	Loss from discontinued operations before taxes	(2,677		)	—			—			(2,677		)
	Income tax benefit	1,114			—			—			1,114
	Net loss from discontinued operations	(1,563		)	—			—			(1,563		)
	Net earnings (loss)	$	30,104		$	147,070		$	(8,269	)	$	168,905
		Year Ended December 31, 2013
		Community			National						Consolidated
Results of Operations:	Banking			Lending			Other			Company
	(In thousands)
Interest income	$	261,492		$	48,422		$	—		$	309,914
Interest expense	(7,873		)	(532		)	(3,796		)	(12,201		)
Intersegment interest income (expense)	1,525			(1,525		)	—			—
Net interest income	255,144			46,365			(3,796		)	297,713
Negative provision (provision) for credit losses	8,079			(3,869		)	—			4,210
Gain on securities	137			—			5,222			5,359
FDIC loss sharing expense	(26,172		)	—			—			(26,172		)
Other noninterest income	21,395			3,558			104			25,057
Total noninterest income	(4,640		)	3,558			5,326			4,244
Foreclosed assets income, net	1,503			—			—			1,503
Intangible asset amortization	(4,748		)	(654		)	—			(5,402		)
Acquisition, integration and reorganization costs	(40,552		)	—			(260		)	(40,812		)
Other noninterest expense	(156,600		)	(23,575		)	(5,801		)	(185,976		)
Total noninterest expense	(200,397		)	(24,229		)	(6,061		)	(230,687		)
Earnings (loss) from continuing operations before taxes	58,186			21,825			(4,531		)	75,480
Income tax (expense) benefit	(24,940		)	(9,101		)	4,038			(30,003		)
Net earnings from continuing operations	33,246			12,724			(493		)	45,477
Loss from discontinued operations before taxes	(620		)	—			—			(620		)
Income tax benefit	258			—			—			258
Net loss from discontinued operations	(362		)	—			—			(362		)
Net earnings (loss)	$	32,884		$	12,724		$	(493	)	$	45,115
	Year Ended December 31, 2012
	Community			National						Consolidated
Results of Operations:	Banking			Lending			Other			Company
	(In thousands)
Interest income	$	251,720		$	44,395		$	—		$	296,115
Interest expense	(15,043		)	(884		)	(3,721		)	(19,648		)
Intersegment interest income (expense)	2,055			(2,055		)	—			—
Net interest income	238,732			41,456			(3,721		)	276,467
Negative provision (provision) for credit losses	14,585			(1,766		)	—			12,819
Gain on securities	1,239			—			—			1,239
FDIC loss sharing expense	(10,070		)	—			—			(10,070		)
Other noninterest income	20,572			4,017			114			24,703
Total noninterest income	11,741			4,017			114			15,872
Foreclosed assets expense, net	(10,931		)	—			—			(10,931		)
Intangible asset amortization	(5,898		)	(428		)	—			(6,326		)
Acquisition, integration and reorganization costs	(4,089		)	—			—			(4,089		)
Debt termination expense	(24,195		)	—			1,597			(22,598		)
Other noninterest expense	(138,640		)	(23,502		)	(5,576		)	(167,718		)
Total noninterest expense	(183,753		)	(23,930		)	(3,979		)	(211,662		)
Earnings (loss) before taxes	81,305			19,777			(7,586		)	93,496
Income tax (expense) benefit	(31,542		)	(8,327		)	3,174			(36,695		)
Net earnings (loss)	$	49,763		$	11,450		$	(4,412	)	$	56,801

Condensed_Financial_Informatio

Condensed Financial Information Of Parent Company (Notes)	12 Months Ended
	Dec. 31, 2014
Condensed Financial Information Of Parent Company [Abstract]
Condensed Financial Information of Parent Company Only Disclosure	CONDENSED FINANCIAL INFORMATION OF PARENT COMPANY
	The following tables present the parent company only condensed balance sheets and the related condensed statements of earnings and condensed statements of cash flows as of and for the years indicated:
	Parent Company Only	December 31,
	Condensed Balance Sheets	2014			2013
		(In thousands)
	Assets:
	Cash and due from banks	$	309,220		$	21,835
	Investments in subsidiaries	3,119,642			911,200
	Other assets	212,157			10,341
	Total assets	$	3,641,019		$	943,376
	Liabilities:
	Subordinated debentures	$	133,232		$	132,645
	Other liabilities	1,362			1,638
	Total liabilities	134,594			134,283
	Stockholders’ equity	3,506,425			809,093
	Total liabilities and stockholders’ equity	$	3,641,019		$	943,376
	Parent Company Only	December 31,
	Condensed Statement of Earnings	2014			2013			2012
		(In thousands)
	Miscellaneous income	$	122		$	104		$	114
	Acquisition‑related securities gain	—			5,222			—
	Debt termination income	—			—			1,597
	Dividends from Bank subsidiary	137,000			48,000			50,000
	Total income	137,122			53,326			51,711
	Interest expense	4,211			3,796			3,721
	Operating expenses	8,105			6,061			5,576
	Total expenses	12,316			9,857			9,297
	Earnings before income taxes and equity in undistributed earnings of subsidiaries	124,806			43,469			42,414
	Income tax benefit	5,164			4,038			3,174
	Earnings before equity in undistributed earnings of subsidiaries	129,970			47,507			45,588
	Equity in undistributed earnings of subsidiaries	38,935			(2,392		)	11,213
	Net earnings	$	168,905		$	45,115		$	56,801
	Parent Company Only	December 31,
	Condensed Statements of Cash Flows	2014			2013			2012
		(In thousands)
	Cash flows from operating activities:
	Net earnings	$	168,905		$	45,115		$	56,801
	Adjustments to reconcile net earnings to net cash provided by operating activities:
	Acquisition‑related securities gain	—			(5,222		)	—
	Change in other assets	39,874			(609		)	711
	Change in liabilities	310			4,932			(4,122		)
	Tax effect in stockholders’ equity of restricted stock vesting	4,625			(364		)	(102		)
	Earned stock compensation	41,099			441			715
	Equity in undistributed (earnings) losses of subsidiaries	(38,935		)	2,392			(11,213		)
	Net cash provided by operating activities	215,878			46,685			42,790
	Cash flows from investing activities:
	Net cash and cash equivalents acquired in acquisition	226,960			857			—
	Purchases of securities available‑for‑sale	—			—			(1,500		)
	Net cash provided by (used in) investing activities	226,960			857			(1,500		)
	Cash flows from financing activities:
	Redemptions of subordinated debentures	—			—			(18,558		)
	Tax effect in stockholders’ equity of restricted stock vesting	(4,625		)	364			102
	Restricted stock surrendered	(22,307		)	(13,537		)	(1,475		)
	Cash dividends paid, net	(114,162		)	(41,006		)	(28,787		)
	Net cash used in financing activities	(141,094		)	(54,179		)	(48,718		)
	Net increase (decrease) in cash and cash equivalents	301,744			(6,637		)	(7,428		)
	Cash and cash equivalents, beginning of year	21,835			28,472			35,900
	Cash and cash equivalents, end of year	$	323,579		$	21,835		$	28,472
	Supplemental disclosure of noncash investing and financing activities:
	Common stock issued for acquisitions	$	2,594,070		$	242,268		$	—

Selected_Quarterly_Financial_D

Selected Quarterly Financial Data Selected Quarterly Financial Data (USD $)	12 Months Ended
	Dec. 31, 2014													Dec. 31, 2013	Dec. 31, 2012
Quarterly Financial Information Disclosure [Abstract]
Treasury Stock Acquired, Average Cost Per Share	$45.16													$38.50	$23.17
Schedule of Quarterly Financial Information [Table Text Block]	The following tables set forth our unaudited quarterly results for the periods indicated:
		Three Months Ended
		December 31,			September 30,			June 30,			March 31,
		2014			2014			2014			2014
		(Dollars in thousands, except per share data)
	Interest income	$	209,696		$	202,356		$	204,363		$	88,360
	Interest expense	(14,713		)	(13,510		)	(11,830		)	(2,345		)
	Net interest income	194,983			188,846			192,533			86,015
	(Provision) negative provision for credit losses	(2,063		)	(5,050		)	(5,030		)	644
	FDIC loss sharing expense, net	(4,360		)	(7,415		)	(8,525		)	(11,430		)
	Gain on securities	—			—			89			4,752
	Other noninterest income	17,063			23,729			16,915			11,369
	Total noninterest income	12,703			16,314			8,479			4,691
	Foreclosed assets (expense) income, net	(1,938		)	(4,827		)	(497		)	1,861
	Acquisition, integration and reorganization costs	(7,381		)	(5,193		)	(86,242		)	(2,200		)
	Other noninterest expense	(83,021		)	(85,609		)	(83,167		)	(50,530		)
	Total noninterest expense	(92,340		)	(95,629		)	(169,906		)	(50,869		)
	Earnings from continuing operations before income taxes	113,283			104,481			26,076			40,481
	Income tax expense	(42,226		)	(42,205		)	(14,846		)	(14,576		)
	Net earnings from continuing operations	71,057			62,276			11,230			25,905
	Loss from discontinued operations before income taxes	(105		)	(8		)	(1,151		)	(1,413		)
	Income tax benefit	47			3			476			588
	Net loss from discontinued operations	(58		)	(5		)	(675		)	(825		)
	Net earnings	$	70,999		$	62,271		$	10,555		$	25,080
	Basic earnings per share:
	Net earnings from continuing operations	$	0.69		$	0.6		$	0.11		$	0.57
	Net earnings	$	0.69		$	0.6		$	0.1		$	0.55
	Diluted earnings per share:
	Net earnings from continuing operations	$	0.69		$	0.6		$	0.11		$	0.57
	Net earnings	$	0.69		$	0.6		$	0.1		$	0.55
		Three Months Ended
		December 31,			September 30,			June 30,			March 31,
		2013			2013			2013			2013
		(Dollars in thousands, except per share data)
	Interest income	$	83,856		$	85,158		$	71,631		$	69,269
	Interest expense	(2,598		)	(2,869		)	(3,158		)	(3,576		)
	Net interest income	81,258			82,289			68,473			65,693
	Negative provision (provision) for credit losses	1,338			4,167			1,842			(3,137		)
	FDIC loss sharing expense, net	(10,593		)	(7,032		)	(5,410		)	(3,137		)
	(Loss) gain on securities	(272		)	5,222			—			409
	Other noninterest income	6,939			6,937			5,613			5,568
	Total noninterest income	(3,926		)	5,127			203			2,840
	Foreclosed assets income, net	569			420			14			500
	Acquisition, integration and reorganization costs	(16,673		)	(5,450		)	(17,997		)	(692		)
	Other noninterest expense	(49,984		)	(51,170		)	(46,233		)	(43,991		)
	Total noninterest expense	(66,088		)	(56,200		)	(64,216		)	(44,183		)
	Earnings from continuing operations before income taxes	12,582			35,383			6,302			21,213
	Income tax expense	(9,135		)	(11,243		)	(1,906		)	(7,719		)
	Net earnings from continuing operations	3,447			24,140			4,396			13,494
	(Loss) earnings from discontinued operations before income taxes	(578		)	39			(81		)	—
	Income tax benefit (expense)	240			(16		)	34			—
	Net (loss) earnings from discontinued operations	(338		)	23			(47		)	—
	Net earnings	$	3,109		$	24,163		$	4,349		$	13,494
	Basic earnings per share:
	Net earnings from continuing operations	$	0.07		$	0.53		$	0.11		$	0.37
	Net earnings	$	0.06		$	0.53		$	0.11		$	0.37
	Diluted earnings per share:
	Net earnings from continuing operations	$	0.07		$	0.53		$	0.11		$	0.37
	Net earnings	$	0.06		$	0.53		$	0.11		$	0.37

Related_Party_Transaction

Related Party Transaction	12 Months Ended
	Dec. 31, 2014
Related Party Transactions [Abstract]
Related Party Transactions	RELATED PARTY TRANSACTIONS
	Castle Creek Financial LLC, or Castle Creek Financial, is an affiliate of Castle Creek Capital LLC, which the Company's Chairman of the Board, Mr. Eggemeyer, is co-founder and chief executive. During 2014, the Bank paid an advisory fee of $9 million to Castle Creek Financial in connection with the CapitalSource Inc. merger. During 2013, the Bank paid an advisory fee of $1.3 million to Castle Creek Financial in connection with the FCAL acquisition. During 2012, the Bank paid an advisory fee of $448,000 to Castle Creek Financial in connection with the American Perspective Bank acquisition. On August 6, 2014, the services agreement dated May 8, 2011, between the Company and Castle Creek Financial was terminated.

Subsequent_Events

Subsequent Events	12 Months Ended
	Dec. 31, 2014
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS
	On February 11, 2015, the Company announced that the Board of Directors had declared a quarterly cash dividend of $0.50 per common share. The cash dividend is payable on March 5, 2015 to stockholders of record at the close of business on February 23, 2015.
	We have evaluated events that have occurred subsequent to December 31, 2014 and have concluded there are no subsequent events that would require recognition in the accompanying consolidated financial statements.

Accounting_Policies_Policies

Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Business Combinations and Other Purchase of Business Transactions, Policy [Policy Text Block]	PacWest Bancorp is a bank holding company registered under the Bank Holding Company Act of 1956, as amended. Our principal business is to serve as the holding company for our Los Angeles‑based wholly-owned banking subsidiary, Pacific Western Bank, which we refer to as “Pacific Western” or the “Bank.” When we say “we,” “our,” or the “Company,” we mean PacWest Bancorp together with its subsidiaries on a consolidated basis. When we refer to “PacWest” or to the holding company, we are referring to PacWest Bancorp, the parent company, on a stand‑alone basis. As of December 31, 2014, we had total assets of $16.2 billion, gross loans and leases of 11.9 billion, total deposits of $11.8 billion and total stockholders' equity of $3.5 billion.
	Pacific Western is a full-service commercial bank offering a broad range of banking products and services including accepting demand, money market, and time deposits and originating loans and leases, including an array of commercial real estate loans and commercial lending products. The Bank has a foundation of locally generated and relationship-based deposits, with 80 full-service branches located primarily in Southern California, extending from San Diego County to California’s Central Coast, and we operate three banking offices in the San Francisco Bay area and four offices in the Central Valley. Our targeted collateral for our real estate loan offerings includes healthcare properties, office properties, industrial properties, multifamily properties, hospitality properties, and retail properties. Our commercial loan products include equipment loans and leases, asset-based loans, loans to finance companies, and loans secured by borrower future cash flows.
	As a result of the CapitalSource Inc. merger, Pacific Western Bank established the CapitalSource Division, which we also refer to as the National Lending segment. The CapitalSource Division lends throughout the United States, providing middle-market businesses asset-secured loans, equipment-secured loans, and cash flow loans and providing real estate investment firms real estate loans secured by various property types. Pacific Western’s leasing operation, Pacific Western Equipment Finance, and its group specializing in asset-based lending, CapitalSource Business Finance Group (formerly BFI Business Finance and First Community Financial), also became part of the CapitalSource Division. The CapitalSource Division’s loan and lease origination efforts are conducted through offices located in Chevy Chase, Maryland; Los Angeles and San Jose, California; St. Louis, Missouri; Denver, Colorado; Chicago, Illinois; New York, New York; and Midvale, Utah. When we refer to "CapitalSource Inc." we are referring to the company acquired on April 7, 2014 and when we refer to the "CapitalSource Division" we are referring to a division of Pacific Western Bank that specializes in middle-market lending on a nationwide basis.
	We generate our revenue primarily from interest received on loans and leases and, to a lesser extent, from interest received on investment securities, and fees received in connection with deposit services, extending credit and other services offered, including foreign exchange services. Our major operating expenses are the interest paid by the Bank on deposits and borrowings, compensation and general operating expenses.
	We have completed 27 acquisitions from May 2000 through December 31, 2014, including the acquisition of CapitalSource Inc. on April 7, 2014. Since 2000, our acquisitions have been accounted for using the acquisition method of accounting and, accordingly, the operating results of the acquired entities have been included in the consolidated financial statements from their respective acquisition dates. See Note 4, Acquisitions, for more information about the CapitalSource Inc. merger, the acquisition of First California Financial Group, Inc. ("FCAL") on May 31, 2013 and our 2012 acquisitions.
Basis of Accounting, Policy [Policy Text Block]	The accounting and reporting policies of the Company are in accordance with U.S. generally accepted accounting principles, which we may refer to as U.S. GAAP. All significant intercompany balances and transactions have been eliminated.
Use of Estimates	Use of Estimates
	Management of the Company has made a number of estimates and assumptions relating to the reporting of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reporting period to prepare these consolidated financial statements in conformity with U.S. GAAP. Actual results could differ from those estimates. Material estimates subject to change in the near term include, among other items, the allowance for credit losses, the carrying value of intangible assets, the carrying value of the FDIC loss sharing asset, and the realization of deferred tax assets.
	As described in Note 4, Acquisitions, below, we completed the merger with CapitalSource Inc. on April 7, 2014, the acquisition of FCAL on May 31, 2013 and three other acquisitions in 2012. The acquired assets and liabilities in each of these acquisitions were measured at their estimated fair values. Management made significant estimates and exercised significant judgment in estimating such fair values and accounting for the acquired assets and assumed liabilities in each of these transactions.
Reclassifications	Reclassifications
	Certain prior period amounts have been reclassified to conform to the current period’s presentation format. On the balance sheet, the "Foreclosed assets, net" category includes other foreclosed assets which were previously reported within the "Other assets" category. On the statement of earnings, the "Other expense" category includes loan-related legal expenses which were previously reported within the "Other professional services" category. In the loan portfolio segment disclosure, the "Equipment finance" class of the "Commercial" loan portfolio segment includes the "Leases" loan portfolio which was previously reported as a separate loan portfolio segment. These reclassifications did not affect previously reported net income.
Cash and Cash Equivalents	Cash and Cash Equivalents
	For purposes of the consolidated statements of cash flows, cash and cash equivalents consist of cash, due from banks, and interest‑earning deposits in financial institutions. Interest‑earning assets in financial institutions represent mostly cash held at the Federal Reserve Bank of San Francisco (“FRBSF”), the majority of which is immediately available.
Investment Securities	Investment Securities
	We determine the classification of securities at the time of purchase. If we have the intent and the ability at the time of purchase to hold securities until maturity, they are classified as held‑to‑maturity. Investment securities held‑to‑maturity are stated at amortized cost. Securities to be held for indefinite periods of time, but not necessarily to be held‑to‑maturity or on a long‑term basis, are classified as available‑for‑sale and carried at estimated fair value, with unrealized gains or losses reported as a separate component of stockholders’ equity in accumulated other comprehensive income, net of applicable income taxes. Securities available‑for‑sale include securities that management intends to use as part of its asset/liability management strategy and that may be sold in response to changes in interest rates, prepayment risk, and other related factors. Securities are individually evaluated for appropriate classification when acquired; consequently, similar types of securities may be classified differently depending on factors existing at the time of purchase.
	The carrying values of all securities are adjusted for amortization of premiums and accretion of discounts over the period to maturity of the related security using the interest method. Realized gains or losses on the sale of securities, if any, are determined using the amortized cost of the specific securities sold. Declines in the fair value of debt securities classified as available-for-sale are reviewed to determine whether the impairment is other-than-temporary. This review considers a number of factors, including the severity of the decline in fair value, current market conditions, historical performance of the security, risk ratings and the length of time the security has been in an unrealized loss position. If we do not expect to recover the entire amortized cost basis of the security, then an other-than-temporary impairment is considered to have occurred. The cost basis of the security is written down to its fair value and the amount of the write‑down is recognized through a charge to earnings.
	Investments in Federal Home Loan Bank of San Francisco, or "FHLB," stock are carried at cost and evaluated regularly for impairment. FHLB stock is expected to be redeemed at par and is a required investment based on measurements of the Bank’s assets and/or borrowing levels.
Loans and Leases	Loans and Leases
	Originated loans. Loans are originated by the Company with the intent to hold them for investment and are stated at the principal amount outstanding, net of unearned income. Unearned income includes deferred unamortized nonrefundable loan fees and direct loan origination costs. Net deferred fees or costs are recognized as an adjustment to interest income over the contractual life of the loans using the effective interest method or taken into income when the related loans are paid off or sold. The amortization of loan fees or costs is discontinued when a loan is placed on nonaccrual status. Interest income is recorded on an accrual basis in accordance with the terms of the respective loan.
	Purchased loans. Purchased loans are stated at the principal amount outstanding, net of unearned discounts or unamortized premiums. All loans acquired in our acquisitions are initially measured and recorded at their fair value on the acquisition date. A component of the initial fair value measurement is an estimate of the credit losses over the life of the purchased loans. Purchased loans are also evaluated for impairment as of the acquisition date and are accounted for as “acquired non‑impaired” or “purchased credit impaired” loans.
	Acquired non‑impaired loans. Acquired non‑impaired loans are those loans for which there was no evidence of credit deterioration at their acquisition date and it was probable that we would be able to collect all contractually required payments. Acquired non‑impaired loans, together with originated loans, are referred to as non‑purchased credit impaired (“Non‑PCI”) loans. Purchase discount or premium on acquired non‑impaired loans is recognized as an adjustment to interest income over the contractual life of such loans using the effective interest method or taken into income when the related loans are paid off or sold.
	Purchased credit impaired loans. Purchased credit impaired (“PCI”) loans are accounted for in accordance with ASC Subtopic 310‑30, “Loans and Debt Securities Acquired with Deteriorated Credit Quality.” A purchased loan is deemed to be credit impaired when there is evidence of credit deterioration since its origination and it is probable at the acquisition date that we would be unable to collect all contractually required payments. We apply PCI loan accounting when we acquire loans deemed to be impaired, and as a general policy election when we acquire a portfolio of loans in a distressed bank acquisition.
	For PCI loans, at the time of acquisition we (i) calculated the contractual amount and timing of undiscounted principal and interest payments (the “undiscounted contractual cash flows”) and (ii) estimated the amount and timing of undiscounted expected principal and interest payments (the “undiscounted expected cash flows”). The difference between the undiscounted contractual cash flows and the undiscounted expected cash flows is the nonaccretable difference. The nonaccretable difference represents an estimate of the loss exposure of principal and interest related to the PCI loan portfolios; such amount is subject to change over time based on the performance of such loans. The carrying value of PCI loans is reduced by payments received, both principal and interest, and increased by the portion of the accretable yield recognized as interest income.
	The excess of the undiscounted expected cash flows at acquisition over the initial fair value of acquired impaired loans is referred to as the “accretable yield” and is recorded as interest income over the estimated life of the loans using the effective yield method if the timing and amount of the future cash flows is reasonably estimable. PCI loans that are contractually past due are still considered to be accruing and performing as long as there is an expectation that the estimated cash flows will be received. If the timing and amount of cash flows is uncertain, then cash payments received will be recognized as a reduction of the recorded investment.
	As part of the fair value process and the subsequent accounting, the Company aggregates PCI loans into pools having common credit risk characteristics such as type and risk rating. Increases in expected cash flows over those previously estimated increase the accretable yield and are recognized as interest income prospectively. Decreases in the amount and changes in the timing of expected cash flows compared to those previously estimated decrease the accretable yield and usually result in a provision for loan losses and the establishment of an allowance for loan losses. As the accretable yield increases or decreases from changes in cash flow expectations, the offset is a decrease or increase to the nonaccretable difference. The accretable yield is measured at each financial reporting date based on information then currently available and represents the difference between the remaining undiscounted expected cash flows and the current carrying value of the loans.
	Covered loans. We refer to loans that are covered by loss sharing agreements with the Federal Deposit Insurance Corporation (“FDIC”) as covered loans. Our covered loans include loans that we acquired in the Los Padres and Affinity acquisitions, and loans that we acquired in the FCAL acquisition where we assumed the loss sharing agreements between First California Bank (“FCB”) and the FDIC related to FCB’s acquisitions of Western Commercial Bank (“Western Commercial”) and San Luis Trust Bank (“San Luis”). We will be reimbursed for a substantial portion of any future losses on such loans under the terms of the FDIC loss sharing agreements. The FDIC loss sharing asset related to covered loans is reported separately in the balance sheet. See “-FDIC Loss Sharing Asset.”
	When we refer to non‑covered loans, we are referring to loans not covered by our loss sharing agreements with the FDIC.
	We apply PCI loan accounting to the majority of the covered loans as such covered loans were deemed to be impaired on the acquisition date. We apply acquired non‑impaired loan accounting to covered revolving credit agreements; mainly home equity loans and commercial asset‑based lines of credit, where the borrower has revolving privileges.
	Leases. We provide equipment financing to our customers through a variety of lease arrangements. The most common arrangement is a direct financing (capital) lease. For direct financing leases, lease receivables are recorded on the balance sheet but the leased property is not, although we generally retain legal title to the leased property until the end of each lease. Direct financing leases are stated at the net amount of minimum lease payments receivable, plus any unguaranteed residual value, less the amount of unearned income and net acquisition discount at the reporting date. Direct lease origination costs are amortized over the weighted average life of the lease portfolio. Leases acquired in an acquisition are initially measured and recorded at their fair value on the acquisition date. Purchase discount or premium on acquired leases is recognized as an adjustment to interest income over the contractual life of the leases using the effective interest method or taken into income when the related leases are paid off. Direct financing leases are subject to our allowance for loans and leases.
	Operating leases represents a line of business where we purchase equipment which is then leased to our customers. We receive periodic rental income payments, which are recorded as noninterest income, and the equipment remains on our balance sheet and is depreciated in line with our fixed asset accounting policy.
	Leases in process. We offer “progress funding” which works similarly to a bridge loan by financing an item to be leased during the construction or build phase. Lessees pay interest on the amount advanced to fund a project at an interest rate implicit in the master lease agreement; such income is deferred until the project funding is complete. The amount of funding advanced during the progress funding period is recorded in other assets. At the end of the progress funding period, we either (i) enter into a lease agreement with the lessee and the deferred income is accreted to interest income using an effective yield method over the life of the lease, or (ii) sell the lease to a third party lender and recognize the deferred income as part of any gain or loss on such sale.
	Loans and Leases Held for Sale. As part of our management of the loans and leases held in our portfolio, we will occasionally transfer loans from held for investment to held for sale. Upon transfer, any associated allowance for loan and lease loss is charged off and the carrying value of the loan is adjusted to the lower of cost or estimated fair value. Gains or losses on the sale of these loans are recorded in noninterest income.
	Delinquent or past due loans and leases. Loans and leases are considered delinquent when principal or interest payments are past due 30 days or more; delinquent loans may remain on accrual status between 30 days and 89 days past due.
	Nonaccrual loans and leases. Loans on which the accrual of interest has been discontinued are designated as nonaccrual loans. The accrual of interest on loans is discontinued when principal or interest payments are past due 90 days or when, in the opinion of management, there is a reasonable doubt as to collectability in the normal course of business. When loans are placed on nonaccrual status, all interest previously accrued but not collected is reversed against current period interest income. Income on nonaccrual loans is subsequently recognized only to the extent that cash is received and the loan’s principal balance is deemed collectable. Loans are restored to accrual status when the loans become both well‑secured and are in the process of collection. Leases are designated as nonaccrual leases when the recognition of interest has been discontinued. The recognition of interest on leases is discontinued when a lessee’s payments are past due 90 days or when, in the opinion of management, there is a reasonable doubt as to collectability. Interest on nonaccrual leases is subsequently recognized only to the extent that cash is received and the lease balance is deemed collectable. Leases are restored to accrual status when the leases become both well secured and are in the process of collection.
	Impaired loans and leases. A loan or lease is considered impaired when it is probable that we will be unable to collect all amounts due according to the contractual terms of the loan or lease agreement. Impaired loans and leases include loans and leases on nonaccrual status and performing restructured loans. Income from impaired loans is recognized on an accrual basis unless the loan is on nonaccrual status. Income from loans on nonaccrual status is recognized to the extent cash is received and when the loan’s principal balance is deemed collectable. We measure impairment of a loan by using the estimated fair value of the collateral, less estimated costs to sell, including senior obligations such as delinquent property taxes, if the loan is collateral‑dependent and the present value of the expected future cash flows discounted at the loan’s effective interest rate if the loan is not collateral‑dependent. The impairment amount on a collateral‑dependent loan is charged‑off to the allowance and the impairment amount on a loan that is not collateral‑dependent is set up as a specific reserve. We measure impairment of a lease based upon the present value of the scheduled lease and residual cash flows, discounted at the lease’s effective interest rate.
	Troubled debt restructurings. A loan is classified as a troubled debt restructuring when we grant a concession to a borrower experiencing financial difficulties. These concessions may include a reduction of the interest rate, principal or accrued interest, extension of the maturity date or other actions intended to minimize potential losses. All loan modifications are evaluated on an individual basis to determine whether such modifications meet the criteria to be classified as a troubled debt restructuring under ASC Subtopic 310‑40, “Troubled Debt Restructurings by Creditors.” Loans restructured at a rate equal to or greater than that of a new loan with comparable market risk at the time the loan is modified may be excluded from restructured loan disclosures in years subsequent to the restructuring if the loans are in compliance with their modified terms.
	A loan that has been placed on nonaccrual status that is subsequently restructured will usually remain on nonaccrual status until the borrower is able to demonstrate repayment performance in compliance with the restructured terms for a sustained period, typically for six months. A restructured loan may return to accrual status sooner based on other significant events or mitigating circumstances. A loan that has not been placed on nonaccrual status may be restructured and such loan may remain on accrual status after such restructuring. In these circumstances, the borrower has made payments before and after the restructuring. Generally, this restructuring involves a reduction in the loan interest rate and/or a change to interest‑only payments for a period of time. The restructured loan is considered impaired despite the accrual status and a specific reserve is calculated based on the present value of expected cash flows discounted at the loan’s original effective interest rate.
Allowance for Credit Losses	Allowances for Credit Losses
	Allowance for credit losses on Non‑PCI loans and leases. The allowance for credit losses on non-purchased credit impaired ("Non-PCI") loans and leases is the combination of the allowance for loan and lease losses and the reserve for unfunded loan commitments. The allowance for loan and lease losses is reported as a reduction of outstanding loan and lease balances and the reserve for unfunded loan commitments is included within "Accrued interest payable and other liabilities." The following discussion is for Non-PCI loans and leases and the allowance for credit losses thereon. Refer to "—Allowance for Credit Losses on Purchased Credit Impaired Loans" for the policy on purchased credit impaired loans. For loans and leases acquired and measured at fair value and deemed non-impaired on the acquisition date, our allowance methodology measures deterioration in credit quality or other inherent risks related to these acquired assets that arise after the acquisition date.
	The allowance for loan and lease losses is maintained at a level deemed appropriate by management to adequately provide for known and inherent risks in the loan and lease portfolio and other extensions of credit at the balance sheet date. The allowance is based upon our continual review of the credit quality of the loan and lease portfolio, which includes loan and lease payment trends, borrowers' compliance with loan agreements, borrowers' current and budgeted financial performance, collateral valuation trends, and current economic factors and external conditions that may affect our borrowers' ability to pay. Loans and leases that are deemed to be uncollectable are charged off and deducted from the allowance. The provision for loan and lease losses and recoveries on loans and leases previously charged off are added to the allowance.
	The allowance for loan and lease losses contains a general reserve component for loans and leases not considered impaired and a specific reserve component for loans and leases determined to be impaired.
	A loan or lease is considered impaired when it is probable that we will be unable to collect all amounts due according to the original contractual terms of the agreement. We assess our loans for impairment on an on-going basis using certain criteria such as payment performance, borrower reported financial results and budgets, and other external factors when appropriate. We measure impairment of a loan based upon the fair value of the loan’s collateral if the loan is collateral-dependent or the present value of cash flows, discounted at the loan’s effective interest rate, if the loan is not collateral-dependent. We measure impairment of a lease based upon the present value of the scheduled lease and residual cash flows, discounted at the lease's effective interest rate. To the extent a loan or lease exceeds the estimated collectable value, a specific reserve or charge-off is recorded depending upon the certainty of the estimate of loss. Smaller balance loans (under $250,000), with a few exceptions for certain loan types, are generally not individually assessed for impairment but are evaluated collectively.
	The methodology we use to estimate the general reserve component of our allowance for credit losses considers both objective and subjective criteria. The objective criteria uses our actual historical loan and lease charge-off experience on pools of similar loans and leases to establish loss factors that are applied to our current loan and lease balances to estimate inherent credit losses. The estimation of the allowance for credit losses at December 31, 2014 considered actual historical loan and lease charge-off experience over a five-year period starting with the fourth quarter of 2009. The five-year period is inclusive of the average timeframe over which charge-offs typically occur following loan or lease origination. The estimation of the allowance for credit losses at December 31, 2013 considered actual historical loan and lease charge-off experience over a four-year period starting with the fourth quarter of 2009. The increase in the historical look-back period from four years at December 31, 2013 to five years at December 31, 2014 allows the fourth quarter of 2009 and all of 2010 loan and lease charge-off experience to continue to be considered in the estimation of the allowance for credit losses. When estimating the general reserve component for the various pools of similar loan types, the loss factors applied to the loan pools consider the current credit risk ratings, giving greater weight to loans with more adverse credit risk ratings. We recognize that the determination of the allowance for loan and lease losses is sensitive to the assigned credit risk ratings and inherent loss rates at any given point in time. To ensure the accuracy of our credit risk ratings, an independent credit review function assesses the ratings assigned to loans on an on-going basis.
	The subjective criteria considered when establishing the loss factors include the following:
	•	current economic trends and forecasts;
	•	current commercial real estate values, performance trends, and overall outlook in the markets where we lend;
	•	legal and regulatory matters that could impact our borrowers’ ability to repay our loans;
	•	our loan portfolio composition and any loan concentrations;
	•	our current lending policies and the effects of any new policies or policy amendments;
	•	our new loan origination volume and the nature of it;
	•	our loan portfolio credit performance trends; and
	•	the results of our on-going independent credit review.
	The reserve for unfunded commitments is estimated using the same loss factors as used for the allowance for loan and lease losses and is computed based only on the expected usage of the unfunded commitments.
	The credit risk ratings assigned to every loan and lease are either “pass,” “special mention,” “substandard” or “doubtful” and defined as follows:
	•	Pass: Loans and leases classified as "pass" are not adversely classified and collection and repayment in full is expected.
	•	Special Mention: Loans and leases classified as "special mention" have a potential weakness that requires management's attention. If not addressed, these potential weaknesses may result in further deterioration in the borrower's ability to repay the loan or lease.
	•	Substandard: Loans and leases classified as "substandard" have a well-defined weakness or weaknesses that jeopardize the collection of the debt. They are characterized by the possibility that we will sustain some loss if the weaknesses are not corrected.
	•	Doubtful: Loans and leases classified as "doubtful" have all the weaknesses of those classified as "substandard," with the additional trait that the weaknesses make collection or repayment in full highly questionable and improbable.
	In addition, we may refer to the loans and leases classified as "substandard" and "doubtful" together as "classified" loans and leases. For further information on classified loans and leases, see Note 7, Loans and Leases.
	Management believes that the allowance for credit losses is appropriate for the known and inherent risks in our Non-PCI loan and lease portfolio and that the credit risk ratings and inherent loss rates currently assigned are appropriate. It is possible that others, given the same information, may at any point in time reach different conclusions that could result in a significant impact to the Company's financial statements. In addition, current credit risk ratings are subject to change as we continue to monitor our loans and leases. To the extent we experience, for example, increased levels of documentation deficiencies, adverse changes in collateral values, or negative changes in economic and business conditions that adversely affect our borrowers, our classified and impaired loans and leases may increase. Higher levels of classified and impaired loans and leases generally result in increased provisions for credit losses and an increased allowances for credit losses. Although we have established an allowance for credit losses that we consider appropriate, there can be no assurance that the established allowance will be sufficient to absorb related losses in the future.
	Our federal and state banking regulators, as an integral part of their examination process, periodically review the Company’s allowance for credit losses. Our regulators may require the Company to recognize additions to the allowance based on their judgments related to information available to them at the time of their examinations.
	Allowance for credit losses on PCI loans. The PCI loans are subject to our internal and external credit review. If deterioration in the expected cash flows results in a reserve requirement, a provision for credit losses is charged to earnings. For PCI loans, the allowance for loan losses is measured at the end of each financial reporting period based on expected cash flows. Decreases or (increases) in the amount and changes in the timing of expected cash flows on the PCI loans as of the financial reporting date compared to those previously estimated are usually recognized by recording a provision or a (negative provision) for credit losses on such loans.
FDIC Loss-Share Agreements	FDIC Loss Sharing Asset
	The FDIC loss sharing asset relates to assets covered by the loss sharing agreements between the Bank and the FDIC arising from the acquisitions of Affinity Bank and Los Padres Bank and, through the FCAL acquisition, the assumption of the loss sharing agreements between First California Bank and the FDIC arising from FCB’s acquisition of Western Commercial and San Luis. The FDIC loss sharing assets related to Western Commercial and San Luis were measured at their fair value as of May 31, 2013 in conjunction with the FCAL acquisition. The FDIC loss sharing assets related to Los Padres and Affinity were measured at their estimated fair value at their respective acquisition dates.
	An increase in the expected amount of losses on the covered assets will increase the FDIC loss sharing asset; such increase is recognized through a credit to FDIC loss sharing income. Recoveries on previous losses paid to us by the FDIC reduce the FDIC loss sharing asset by a charge to FDIC loss sharing income. In addition, decreases in the expected amount of losses on covered assets will decrease the amount of funds expected to be collected from the FDIC and will therefore reduce the FDIC loss sharing asset through higher prospective amortization expense. The FDIC loss sharing asset is being amortized to its estimated value over the lesser of the term of the loss sharing agreements or the remaining contractual life of the assets covered by the loss sharing agreements.
	Both the Western Commercial and San Luis loss sharing agreements contain true‑up provisions, under which we will owe the FDIC amounts at the end of the loss sharing agreements based on the performance of the covered assets. The true‑up liability is included in other liabilities in the accompanying consolidated balance sheets.
	Under the terms of the Affinity loss sharing agreement, the FDIC will (a) absorb 80% of losses and receive 80% of loss recoveries on the first $234 million of losses on covered assets and (b) absorb 95% of losses and receive 95% of loss recoveries on losses exceeding $234 million. The Affinity loss sharing provisions expired in the third quarter of 2014 for non single-family assets and will expire in the third quarter of 2019 for single family covered assets, while the related loss recovery provisions expire in the third quarters of 2017 and 2019, respectively.
	Under the terms of the Los Padres loss sharing agreement, the FDIC will absorb 80% of losses and receive 80% of loss recoveries on the covered assets. The Los Padres loss sharing provisions expire in the third quarters of 2015 and 2020 for non‑single family and single family covered assets, respectively, while the related loss recovery provisions expire in the third quarters of 2018 and 2020, respectively.
	Under the terms of the Western Commercial loss sharing agreement, the FDIC will absorb 80% of losses and receive 80% of loss recoveries on the covered assets; all of which were deemed to be non‑single family. The Western Commercial loss sharing provision expires in the fourth quarter of 2015, while the related loss recovery provision expires in the fourth quarter of 2018.
	Under the terms of the San Luis loss sharing agreement, the FDIC will absorb 80% of losses and receive 80% of loss recoveries on the covered assets. The San Luis loss sharing provisions expire in the first quarters of 2016 and 2021 for non‑single family and single family covered assets, respectively, while the related loss recovery provisions expire in the first quarters of 2019 and 2021, respectively.
Land, Premises and Equipment	Land, Premises and Equipment
	Premises and equipment are stated at cost less accumulated depreciation and amortization. Land is not depreciated. Depreciation and amortization is charged to noninterest expense using the straight‑line method over the estimated useful lives of the assets. The estimated useful lives of furniture, fixtures and equipment range from 3 to 7 years and for buildings up to 35 years. Leasehold improvements are amortized over their estimated useful lives, or the life of the lease, whichever is shorter.
Foreclosed Assets	Foreclosed Assets
	Non‑covered Foreclosed Assets. Foreclosed assets includes other real estate owned, or OREO, and repossessed non-real estate assets. Foreclosed assets are initially recorded at the estimated fair value of the property, based on current independent appraisals obtained at the time of acquisition, less estimated costs to sell, including senior obligations such as delinquent property taxes. The excess of the recorded loan balance over the estimated fair value of the property at the time of acquisition less estimated costs to sell is charged to the allowance for loan losses. Any subsequent write‑downs are charged to noninterest expense and recognized through a foreclosed assets valuation allowance. Subsequent increases in the fair value of the asset less selling costs reduce the foreclosed assets valuation allowance, but not below zero, and are credited to noninterest expense. Gains and losses on the sale of foreclosed assets and operating expenses of such assets are also included in noninterest expense.
	Covered OREO. Covered OREO are initially recorded at its estimated fair value on the acquisition date based on independent appraisals less estimated selling costs. Any subsequent write‑downs due to declines in fair value are charged to noninterest expense, and any recoveries of previous write-downs are credited to noninterest expense, without regard to the FDIC indemnification. The portion of the loss reimbursement or recovery due from or to the FDIC is recognized as FDIC loss sharing income or expense.
Income Taxes	Income Taxes
	Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in earnings in the period that includes the enactment date. Any interest or penalties assessed by the taxing authorities is classified in the financial statements as income tax expense. Deferred tax assets and liabilities, net of valuation allowances, are grouped together and reported net on the consolidated balance sheets.
	On a quarterly basis, the Company evaluates its deferred tax assets to assess whether they are expected to be realized in the future. This determination is based on currently available facts and circumstances, including our current and projected future tax positions, the historical level of our taxable income, and estimates of our future taxable income. In most cases, the realization of deferred tax assets is based on our future profitability. To the extent our deferred tax assets are no longer considered more likely than not to be realized, we could be required to record a valuation allowance on our deferred tax assets by charging earnings. The Company also evaluates existing valuation allowances periodically to determine if sufficient evidence exists to support an increase or reduction in the allowance.
Goodwill and Intangible Assets	Goodwill and Other Intangible Assets
	Goodwill arises from the acquisition method of accounting for business combinations and represents the excess of the purchase price over the fair value of the net assets and other identifiable intangible assets acquired. Goodwill and other intangible assets deemed to have indefinite lives generated from purchase business combinations are not subject to amortization and are instead tested for impairment no less than annually. Impairment exists when the carrying value of the goodwill exceeds its implied fair value. An impairment loss would be recognized in an amount equal to that excess as a charge to noninterest expense in the consolidated statement of earnings.
	Intangible assets with estimable useful lives are amortized over such useful lives to their estimated residual values and reviewed for impairment at least quarterly. Core deposit intangible assets, which we refer to as CDI, and customer relationship intangible assets, which we refer to as CRI, are recognized apart from goodwill at the time of acquisition based on market valuations prepared by independent third parties. In preparing such valuations, the third parties consider variables such as deposit servicing costs, attrition rates, and market discount rates. CDI assets are amortized to expense over their useful lives, which we have estimated to range from 7 to 10 years. CRI assets are amortized to expense over their useful lives, which we have estimated to range from 4 to 5 years. The amortization expense represents the estimated decline in the value of the underlying deposits or customer relationships acquired. Both CDI and CRI are reviewed for impairment quarterly or earlier if events or changes in circumstances indicate that their carrying values may not be recoverable. If the recoverable amount of either CDI or CRI is determined to be less than its carrying value, we would then measure the amount of impairment based on an estimate of the intangible asset’s fair value at that time. If the fair value is below the carrying value, then the intangible asset is reduced to such fair value; an impairment loss for such amount would be recognized as a charge to noninterest expense in the consolidated statement of earnings.
Stock-based Compensation	Stock‑Based Compensation
	Compensation expense related to awards of time-based restricted stock is based on the fair value of the underlying stock on the award date and is recognized over the vesting period using the straight‑line method. The vesting of performance‑based restricted stock awards and recognition of related compensation expense may occur over a shorter vesting period if financial performance targets are achieved earlier than anticipated. Amortization of unvested performance‑based restricted stock is suspended when it becomes less than probable that the performance targets will be met. Amortization of unvested performance‑based restricted stock is discontinued and previous amortization amounts are credited to earnings when it becomes improbable that performance targets will be met. When and if it becomes probable in the future that the performance target will be met a catch up adjustment is made and amortization resumes.
	Unvested restricted stock participates with common stock in any dividends declared and paid. Dividends paid on unvested restricted stock awards expected to vest and the related tax benefits are included as a net reduction to stockholders’ equity. Dividends paid on unvested restricted stock not expected to vest are charged to compensation expense.
Business Segments	Business Segments
	We present financial and descriptive information about our reportable operating segments including a measure of segment profit or loss, certain specific revenue and expense items and segment assets. We designate components of our business as reportable operating segments if the component a) engages in business activities from which it may earn revenues and incur expenses, b) has operating results that are regularly reviewed by executive management to make business decisions about resources to be allocated to the segment and assess its performance and c) has available discrete financial information. We currently operate as three reportable segments. The Company’s reportable segments consist of “Community Banking," “National Lending,” and “Other.”
Derivatives, Policy [Policy Text Block]	(o) Derivative Instruments
	Our derivative contracts primarily manage the foreign currency risk associated with certain assets. As of December 31, 2014, all of our derivatives were held for risk management purposes, and none were designated as accounting hedges. The objective is to manage the uncertainty of future foreign exchange rate fluctuations. These forward exchange contracts provide for a fixed exchange rate which has the effect of reducing or eliminating changes to anticipated cash flows to be received from foreign currency-denominated loan transactions as the result of changes to exchange rates. Our derivatives are recorded in other assets or other liabilities, as appropriate. The changes in fair value of our derivatives and the related interest are recognized in other income. At December 31, 2014, our derivative contracts had a notional value of $67.8 million.
	Derivative instruments expose us to credit risk in the event of nonperformance by counterparties to such agreements. This risk exposure consists primarily of the termination value of agreements where we are in a favorable position. We manage the credit risk associated with various derivative agreements through counterparty credit review and monitoring procedures.
Equity Method Investments, Policy [Policy Text Block]	Investments That Do Not Have Readily Determinable Fair Values
	Investments in common or preferred stock that are not publicly traded and/or do not have a readily determinable fair value are accounted for pursuant to the equity method of accounting if we have the ability to significantly influence the operating and financial policies of an investee. This is generally presumed to exist when we own between 20% and 50% of a corporation, or when we own greater than 5% of a limited partnership or similarly structured entity. Our investment carrying values are included in other assets and our share of earnings and losses in equity method investees is included in other income. If we do not have significant influence over the investee, the cost method is used to account for the equity interest.
	For investments accounted for using the cost or equity method of accounting, management evaluates information such as budgets, business plans, and financial statements of the investee in addition to quoted market prices, if any, in determining whether an other-than-temporary decline in value exists. Factors indicative of an other-than-temporary decline in value include, but are not limited to, recurring operating losses and credit defaults. We compare the estimated fair value of each investment to its carrying value quarterly. For any of our investments in which the estimated fair value is less than its carrying value, we consider whether the impairment of that investment is other-than-temporary. If we determine that an investment has sustained an other-than-temporary decline in its value, the equity interest is written down to its estimated fair value through other income and a new carrying value for the investment is established.
	Realized gains or losses resulting from the sale of investments are calculated using the specific identification method and are included in other income.
Comprehensive Income	Comprehensive Income
	Comprehensive income consists of net earnings and net unrealized gains (losses) on securities available‑for‑sale, net, and is presented in the consolidated statements of comprehensive income.
Earnings Per Share	Earnings Per Share
	In accordance with ASC Topic 260, “Earnings Per Share,” all outstanding unvested share‑based payment awards that contain rights to nonforfeitable dividends are considered participating securities and are included in the two‑class method of determining basic and diluted earnings per share. All of our unvested restricted stock participates with our common stockholders in dividends. Accordingly, earnings allocated to unvested restricted stock are deducted from net earnings to determine that amount of earnings available to common stockholders. In the two‑class method, the amount of our earnings available to common stockholders is divided by the weighted average shares outstanding, excluding any unvested restricted stock, for both the basic and diluted earnings per share.
Business Combinations	Business Combinations
	Business combinations completed after January 1, 2009, are accounted for under the acquisition method of accounting in accordance with ASC Topic 805, “Business Combinations.” Under the acquisition method, the acquiring entity in a business combination recognizes 100 percent of the acquired assets and assumed liabilities, regardless of the percentage owned, at their estimated fair values as of the date of acquisition. Any excess of the purchase price over the fair value of net assets and other identifiable intangible assets acquired is recorded as goodwill. To the extent the fair value of net assets acquired, including other identifiable assets, exceeds the purchase price, a bargain purchase gain is recognized. Assets acquired and liabilities assumed from contingencies must also be recognized at fair value, if the fair value can be determined during the measurement period. Results of operations of an acquired business are included in the statement of earnings from the date of acquisition. Acquisition‑related costs, including conversion and restructuring charges, are expensed as incurred.
Recently issued Accounting Standards	Recently Issued Accounting Standards
	In January 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014‑01, “Investments-Equity Method and Joint Ventures (Topic 323): Accounting for Investments in Qualified Affordable Housing Projects.” ASU 2014‑01 allows investors in low‑income housing tax credit (“LIHTC”) entities that meet certain conditions to present the net tax benefits (net of the amortization of the cost of the investment) within income tax expense. The cost of the investments that meet the conditions will be amortized in proportion to (and over the same period as) the total expected tax benefits, including tax credits and other tax benefits, as they are realized on the tax return. ASU 2014‑01 is effective for us on January 1, 2015 and is to be applied retrospectively if investors elect the proportional amortization method. However, if investors have LIHTC investments accounted for under the effective yield method at adoption, they may continue to apply that method for those existing investments. The adoption of this standard permits expenses currently reported in noninterest expense to be reported in income tax expense. Early adoption was permitted. We adopted this standard effective January 1, 2015, elected the proportional amortization method, and it is not expected to have a material impact on our financial statements; however, total noninterest expense and income tax expense will change.
	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 a creditor should reclassify mortgage loans collateralized by residential real estate from loans receivable to other real estate owned. ASU 2014‑04 defines when an in‑substance repossession or foreclosure has occurred and when a creditor is considered to have received physical possession of residential real estate collateralizing a mortgage loan. ASU 2014‑04 was effective for us on January 1, 2015 and can be applied either prospectively or using a modified retrospective transition method, and early adoption was permitted. The adoption of this standard in January 2015 will not have a material impact on our financial statements.
	In April 2014, the FASB issued ASU 2014-08, "Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity." ASU 2014-08 is an amendment to Subtopic 205-20 that changes the criteria for reporting discontinued operations by raising the threshold for disposals to qualify as discontinued operations. This update aims to reduce the unnecessarily frequent reporting of disposals of small groups of assets that are recurring in nature. The revised definition states that a disposal of a component of an entity or a group of components of an entity is required to be reported in discontinued operations if the disposal represents a strategic shift that has (or will have) a major effect on an entity’s operations and financial results. ASU 2014-08 is effective for us for all disposals that occur after December 31, 2014. The adoption of this standard is not expected to have a material impact on our financial statements.
	ASU 2014-09, "Revenue Recognition (Topic 606): Revenue from Contracts with Customers," was issued May 2014 and will be effective for annual and interim periods beginning after December 15, 2016. Early application is not permitted. ASU 2014-09 requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. ASU 2014-09 will replace most existing revenue recognition guidance in GAAP when it becomes effective. The standard permits the use of either the retrospective or cumulative effect transition method. The Company is evaluating the effect that ASU 2014-09 will have on its financial statements and related disclosures. The Company has not yet selected a transition method nor has it determined the effect of the standard on its ongoing financial reporting.
	ASU 2014-12, "Compensation-Stock Compensation (Topic 718): Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period," was issued June 2014 and will be effective for annual and interim periods beginning after December 15, 2015. ASU 2014-12 applies to all reporting entities that grant their employees share-based payments in which the terms of the award provide for a performance target that affects vesting could be achieved after the requisite service period. That is the case when an employee is eligible to retire or otherwise terminate employment before the end of the period in which a performance target (for example, an initial public offering or a profitability target) could be achieved and still be eligible to vest in the award if and when the performance target is achieved. We do not currently have outstanding performance-based awards and, as a result, ASU 2014-12 would not impact our financial statements and its related disclosures.
	In August 2014, the FASB issued ASU 2014-14, "Receivables - Troubled Debt Restructuring by Creditors (Subtopic 310-40): Classification of Certain Government-Guaranteed Mortgage Loans Upon Foreclosure." This ASU requires that a mortgage loan be derecognized and that a separate other receivable be recognized upon foreclosure if the following conditions are met: (1) the loan has a government guarantee that is not separable from the loan before foreclosure; (2) at the time of foreclosure, the creditor has the intent to convey the real estate property to the guarantor and make a claim on the guarantee, and the creditor has the ability to recover under that claim; and (3) at the time of foreclosure, any amount of the claim that is determined on the basis of the fair value of the real estate is fixed. Upon foreclosure, the separate other receivable should be measured based on the amount of the loan balance (principal and interest) expected to be recovered from the guarantor. ASU 2014-14 is effective for public business entities for reporting periods, including interim periods, beginning after December 15, 2014. The Company does not expect the effect of ASU 2014-14 to have a material impact on its financial statements and related disclosures.

Acquisitions_Tables

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2014
Business Combinations [Abstract]
Schedule of Business Acquisitions, by Acquisition	The following assets acquired and liabilities assumed of the acquired entities are presented at estimated fair value as of their respective acquisition dates:
		Acquisition and Date Acquired
		CapitalSource Inc.		First California Financial Group		American Perspective Bank		Celtic Capital Corporation		Pacific Western Equipment Finance
		7-Apr-14		31-May-13		1-Aug-12		3-Apr-12		3-Jan-12
		(In thousands)
	Assets Acquired:
	Cash and due from banks	$	768,553	$	6,124	$	3,370	$	3,435	$	7,092
	Interest‑earning deposits in financial institutions	60,612		266,889		10,081		—		—
	Investment securities available‑for‑sale	382,797		4,444		48,887		—		—
	FHLB stock	46,060		9,518		1,412		—		—
	Loans and leases	6,877,427		1,049,613		197,279		54,963		140,959
	Equipment leased to others under operating leases	160,015		—		—		—		—
	Premises and equipment	12,663		15,322		—		—		—
	Foreclosed assets	6,382		13,772		1,561		—		—
	FDIC loss sharing asset	—		17,241		—		—		—
	Income tax assets	312,757		33,360		2,194		19		—
	Goodwill	1,518,381		129,070		15,047		6,645		19,033
	Core deposit and customer relationship intangibles	6,720		7,927		1,924		1,300		1,700
	Leases in process	—		—		—		—		19,162
	Other assets(1)	582,985		27,576		2,040		720		1,887
	Total assets acquired	$	10,735,352	$	1,580,856	$	283,795	$	67,082	$	189,833
	Liabilities Assumed:
	Noninterest‑bearing deposits	$	4,631	$	361,166	$	40,673	$	—	$	—
	Interest‑bearing deposits	6,236,419		739,713		178,891		—		—
	Other borrowings	992,109		—		5,315		46,804		15,839
	Borrowings from parent	—		—		—		—		128,677
	Subordinated debentures	300,918		24,061		—		—		—
	Discontinued operations	—		184,619		—		—		—
	Accrued interest payable and other liabilities	124,087		19,729		840		2,278		10,317
	Total liabilities assumed	$	7,658,164	$	1,329,288	$	225,719	$	49,082	$	154,833
	Total consideration paid	$	3,077,188	$	251,568	$	58,076	$	18,000	$	35,000
	Summary of consideration:
	Cash paid	$	483,118	$	—	$	58,076	$	18,000	$	35,000
	PacWest common stock issued	2,594,070		242,268		—		—		—
	Cancellation of FCAL common stock owned by PacWest (at acquisition date fair value)	—		9,300		—		—		—
	Total	$	3,077,188	$	251,568	$	58,076	$	18,000	$	35,000
Business Acquisition, Integration, Restructuring and Other Related Costs	The following table presents acquisition, integration and reorganization costs by major category for the years indicated:
		Year Ended December 31,
		2014		2013		2012
		(In thousands)
	Severance and employee-related(1)	$	57,868	$	21,497	$	260
	System conversion and integration	1,868		3,829		1,312
	Asset writedowns, lease terminations and other facilities-related	6,353		3,212		—
	Asset financing segment reorganization	10,073		—		—
	Investment banking deal costs	16,117		5,309		1,298
	Other (legal, accounting, insurance, consulting)	8,737		6,965		1,219
	Total acquisition, integration and reorganization costs	$	101,016	$	40,812	$	4,089
Business Acquisition, Pro Forma Information	No assumptions have been applied to the pro forma results of operations regarding possible revenue enhancements, expense efficiencies or asset dispositions.
		Year Ended December 31,
		2014		2013
		(Dollars in thousands, except per share data)
	Pro forma revenues (net interest income plus noninterest income)	$	797,296	$	833,373
	Pro forma net earnings from continuing operations	$	252,258	$	251,347
	Pro forma net earnings from continuing operations per share:
	Basic	$	2.45	$	2.46
	Diluted	$	2.45	$	2.46

Goodwill_and_Other_Intangible_1

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill Disclosure	The following table presents the changes in the carrying amount of goodwill for the years indicated:
		Goodwill
		(In thousands)
	Balance, December 31, 2011	$	39,141
	Addition from the EQF acquisition	19,033
	Addition from the Celtic acquisition	6,645
	Addition from the APB acquisition	15,047
	Balance, December 31, 2012	79,866
	Adjustment to APB goodwill	(193		)
	Addition from the FCAL acquisition	129,070
	Balance, December 31, 2013	208,743
	Addition from the CapitalSource Inc. merger	1,518,381
	Write-off due to the asset financing segment reorganization	(6,645		)
	Balance, December 31, 2014	$	1,720,479
Intangible Assets Disclosure	The following table presents the changes in CDI and CRI and the related accumulated amortization for the years indicated:
		Year Ended December 31,
		2014			2013			2012
		(In thousands)
	Gross Amount of CDI and CRI:
	Balance, beginning of year	$	48,963		$	45,412		$	67,100
	Additions due to acquisitions	6,720			7,927			4,924
	Fully amortized portion	(1,293		)	(4,376		)	(20,746		)
	Write-off due to the asset financing segment reorganization	(1,300		)	—			—
	Removal due to branch sale	—			—			(5,866		)
	Balance, end of year	53,090			48,963			45,412
	Accumulated Amortization:
	Balance, beginning of year	(31,715		)	(30,689		)	(49,685		)
	Additions	(6,268		)	(5,402		)	(6,326		)
	Fully amortized portion	1,293			4,376			20,746
	Write-off due to the asset financing segment reorganization	804			—			—
	Removal due to branch sale	—			—			4,576
	Balance, end of period	(35,886		)	(31,715		)	(30,689		)
	Net CDI and CRI, end of year	$	17,204		$	17,248		$	14,723

Investments_Tables

Investments (Tables)	12 Months Ended
	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Schedule of Available-for-sale Securities Reconciliation	The following table presents amortized cost, gross unrealized gains and losses, and carrying values of securities available-for-sale as of the dates indicated:
		31-Dec-14											31-Dec-13
		Amortized Cost		Gross Unrealized Gains			Gross Unrealized Losses			Fair Value			Amortized Cost		Gross Unrealized Gains			Gross Unrealized Losses			Fair Value
		(In thousands)
	Residential mortgage-backed securities:
	Government agency and
	government-sponsored enterprise
	pass-through securities	$	515,902	$	20,142		$	(372	)	$	535,672		$	691,944	$	18,012		$	(2,768	)	$	707,188
	Government agency and
	government-sponsored enterprise
	collateralized mortgage obligations	275,513		3,513			(1,080		)	277,946			197,069		388			(4,584		)	192,873
	Covered private label collateralized
	mortgage obligations	26,889		7,153			(95		)	33,947			30,502		7,552			(150		)	37,904
	Other private label collateralized
	mortgage obligations	10,961		46			(93		)	10,914			—		—			—			—
	Municipal securities	521,499		15,899			(1,282		)	536,116			459,182		1,749			(24,273		)	436,658
	Corporate debt securities	110,074		597			(562		)	110,109			84,119		71			(1,483		)	82,707
	Government-sponsored enterprise debt
	securities	36,232		525			—			36,757			10,046		—			(174		)	9,872
	Other securities	25,801		33			(118		)	25,716			27,654		2			(113		)	27,543
	Total	$	1,522,871	$	47,908		$	(3,602	)	$	1,567,177		$	1,500,516	$	27,774		$	(33,545	)	$	1,494,745
Unrealized losses on investment securities	Unrealized Losses on Investment Securities
	The following tables present the gross unrealized losses and fair values of securities available-for-sale that were in unrealized loss positions, for which other-than-temporary impairments have not been recognized in earnings, as of the dates indicated:
		31-Dec-14
		Less Than 12 Months					12 Months or More						Total
		Fair Value		Gross Unrealized Losses			Fair Value			Gross Unrealized Losses			Fair Value		Gross Unrealized Losses
		(In thousands)
	Residential mortgage-backed securities:
	Government agency and government-
	sponsored enterprise pass-through
	securities	$	10,711	$	(13	)	$	27,100		$	(359	)	$	37,811	$	(372	)
	Government agency and government-
	sponsored enterprise collateralized
	mortgage obligations	23,908		(73		)	40,652			(1,007		)	64,560		(1,080		)
	Covered private label collateralized
	mortgage obligations	—		—			1,000			(95		)	1,000		(95		)
	Other private label collateralized
	mortgage obligations	1,618		(93		)	—			—			1,618		(93		)
	Municipal securities	11,854		(66		)	84,822			(1,216		)	96,676		(1,282		)
	Corporate debt securities	52,071		(547		)	10,131			(15		)	62,202		(562		)
	Other securities	6,440		(90		)	10,019			(28		)	16,459		(118		)
	Total	$	106,602	$	(882	)	$	173,724		$	(2,720	)	$	280,326	$	(3,602	)
		31-Dec-13
		Less Than 12 Months					12 Months or More						Total
		Fair Value		Gross Unrealized Losses			Fair Value			Gross Unrealized Losses			Fair Value		Gross Unrealized Losses
		(In thousands)
	Residential mortgage-backed securities:
	Government agency and government-
	sponsored enterprise pass-through
	securities	$	148,662	$	(2,767	)	$	32		$	(1	)	$	148,694	$	(2,768	)
	Government agency and government-
	sponsored enterprise collateralized
	mortgage obligations	179,938		(4,486		)	4,383			(98		)	184,321		(4,584		)
	Covered private label collateralized
	mortgage obligations	1,640		(60		)	617			(90		)	2,257		(150		)
	Municipal securities	337,208		(24,273		)	—			—			337,208		(24,273		)
	Corporate debt securities	72,636		(1,483		)	—			—			72,636		(1,483		)
	Government-sponsored enterprise debt
	securities	9,872		(174		)	—			—			9,872		(174		)
	Other securities	23,969		(113		)	—			—			23,969		(113		)
	Total	$	773,925	$	(33,356	)	$	5,032		$	(189	)	$	778,957	$	(33,545	)
Investments Classified by Contractual Maturity Date	The following table presents the contractual maturities of our available-for-sale securities portfolio based on amortized cost and carrying value as of the date indicated.
		31-Dec-14
		Amortized Cost		Estimated Fair Value
		(In thousands)
	Due in one year or less	$	4,567	$	4,596
	Due after one year through five years	85,288		85,219
	Due after five years through ten years	262,556		268,665
	Due after ten years	1,170,460		1,208,697
	Total securities available-for-sale	$	1,522,871	$	1,567,177
Investment Income	The following table presents the composition of our interest income on investment securities for the years indicated:
		Year Ended December 31,
		2014		2013			2012
		(In thousands)
	Taxable interest	$	30,135	$	23,542		$	29,652
	Non-taxable interest	13,597		11,777			5,559
	Dividend income	3,613		1,604			446
	Total interest income on investment securities	$	47,345	$	36,923		$	35,657

Loans_and_Leases_Tables

Loans and Leases (Tables)	12 Months Ended
	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Schedule Of Composition of Loans Portfolio	The following table summarizes the composition of our loan and lease portfolio as of the dates indicated:
		December 31, 2014												December 31, 2013
		Non-PCI												Non-PCI
		Loans				PCI								Loans				PCI
		and Leases				Loans				Total				and Leases				Loans			Total
		(In thousands)
	Real estate mortgage	$	5,350,827			$	256,489			$	5,607,316			$	2,424,864			$	371,134		$	2,795,998
	Real estate construction	309,162				6,924				316,086				209,090				10,427			219,517
	Commercial	5,852,420				27,155				5,879,575				1,241,776				974			1,242,750
	Consumer	101,423				284				101,707				54,809				261			55,070
	Total gross loans and leases	11,613,832				290,852				11,904,684				3,930,539				382,796			4,313,335
	Deferred fees and costs	(22,191		)		(61		)		(22,252		)		(983		)		—			(983		)
	Total loans and leases, net of unearned income	11,591,641				290,791				11,882,432				3,929,556				382,796			4,312,352
	Allowance for loan and lease losses	(70,456		)		(13,999		)		(84,455		)		(60,241		)		(21,793		)	(82,034		)
	Total net loans and leases	$	11,521,185			$	276,792			$	11,797,977			$	3,869,315			$	361,003		$	4,230,318
Schedule of Valuation and Qualifying Accounts Disclosure [Text Block]	The following table presents a summary of the activity in the allowance for credit losses on Non‑PCI loans and leases for the years indicated:
		Components								Total
		Non-PCI				Non-PCI				Non-PCI
		Allowance for				Reserve for				Allowance
		Loan and lease				Unfunded Loan				for Credit
		Losses				Commitments				Losses
		(In thousands)
	Balance, December 31, 2011	$	85,313			$	8,470			$	93,783
	Charge-offs	(13,070		)		—				(13,070		)
	Recoveries	3,406				—				3,406
	Negative provision	(9,750		)		(2,250		)		(12,000		)
	Balance, December 31, 2012	65,899				6,220				72,119
	Charge-offs	(11,159		)		—				(11,159		)
	Recoveries	6,856				—				6,856
	(Negative provision ) provision	(1,355		)		1,355				—
	Balance, December 31, 2013	60,241				7,575				67,816
	Charge-offs	(11,875		)		—				(11,875		)
	Recoveries	10,344				—				10,344
	(Negative provision) provision	11,746				(1,264		)		10,482
	Balance, December 31, 2014	$	70,456			$	6,311			$	76,767
Allowance for Loan Losses	The following tables present a summary of the activity in the allowance for loan and lease losses on Non‑PCI loans and leases by portfolio segment and PCI loans for the years indicated:
		Year Ended December 31, 2014
		Real Estate Mortgage				Real Estate Construction				Commercial				Consumer				Total Non-PCI			Total PCI			Total
		(In thousands)
	Allowance for Loan and Lease Losses:
	Balance, beginning of year	$	26,078			$	4,298			$	26,921			$	2,944			$	60,241		$	21,793		$	82,034
	Charge-offs	(2,080		)		—				(9,463		)		(332		)		(11,875		)	(9,577		)	(21,452		)
	Recoveries	2,640				156				6,265				1,283				10,344			766			11,110
	Provision (negative provision)	(1,541		)		(206		)		16,135				(2,642		)		11,746			1,017			12,763
	Balance, end of year	$	25,097			$	4,248			$	39,858			$	1,253			$	70,456		$	13,999		$	84,455
	Amount of the allowance applicable to loans and leases:
	Individually evaluated for impairment	$	693			$	69			$	9,975			$	37			$	10,774
	Collectively evaluated for impairment	$	24,404			$	4,179			$	29,883			$	1,216			$	59,682
	Acquired loans with deteriorated credit quality																				$	13,999
	Loan and Leases:
	Ending balance(1)	$	5,340,560			$	307,135			$	5,842,463			$	101,483			$	11,591,641		$	290,791		$	11,882,432
	The ending balance of the loan and lease portfolio is composed of loans and leases:
	Individually evaluated for impairment	$	57,857			$	10,555			$	46,709			$	3,744			$	118,865
	Collectively evaluated for impairment	$	5,282,703			$	296,580			$	5,795,754			$	97,739			$	11,472,776
	Acquired loans with deteriorated credit quality																				$	290,791
	_________________________
	-1	As of December 31, 2014, the amounts of loans covered by loss sharing provisions of FDIC loss sharing agreements in the Non-PCI and PCI categories were $61.5 million and $100.4 million.
		Year Ended December 31, 2013
		Real Estate Mortgage				Real Estate Construction				Commercial				Consumer				Total Non-PCI			Total PCI			Total
		(In thousands)
	Allowance for loan and lease losses:
	Balance, beginning of year	$	38,700			$	3,221			$	22,252			$	1,726			$	65,899		$	26,069		$	91,968
	Charge-offs	(4,552		)		—				(6,409		)		(198		)		(11,159		)	(66		)	(11,225		)
	Recoveries	2,507				1,654				2,621				74				6,856			—			6,856
	Provision (negative provision)	(10,577		)		(577		)		8,457				1,342				(1,355		)	(4,210		)	(5,565		)
	Balance, end of year	$	26,078			$	4,298			$	26,921			$	2,944			$	60,241		$	21,793		$	82,034
	Amount of the allowance applicable to loans and leases:
	Individually evaluated for impairment	$	2,188			$	169			$	5,003			$	240			$	7,600
	Collectively evaluated for impairment	$	23,890			$	4,129			$	21,918			$	2,704			$	52,641
	Acquired loans with deteriorated credit quality																				$	21,793
	Loan and Leases:
	Ending balance(1)	$	2,422,107			$	207,779			$	1,244,785			$	54,885			$	3,929,556		$	382,796		$	4,312,352
	The ending balance of the loan and lease portfolio is composed of loans and leases:
	Individually evaluated for impairment	$	62,276			$	7,512			$	17,932			$	702			$	88,422
	Collectively evaluated for impairment	$	2,359,831			$	200,267			$	1,226,853			$	54,183			$	3,841,134
	Acquired loans with deteriorated credit quality																				$	382,796
	_________________________
	-1	As of December 31, 2013, the amounts of loans covered by loss sharing provisions of FDIC loss sharing agreements in the Non-PCI and PCI categories were $85.9 million and $362.5 million.
CV of Loans Held for Investment by class by performing and nonperforming	The following table presents the credit risk rating categories for Non‑PCI loans and leases by portfolio segment and class as of the dates indicated. Nonclassified loans and leases are those with a credit risk rating of either pass or special mention, while classified loans and leases are those with a credit risk rating of either substandard or doubtful.
		31-Dec-14												December 31, 2013
		Classified				Nonclassified				Total				Classified				Nonclassified			Total
		(In thousands)
	Real estate mortgage:
	Hospitality	$	17,761			$	542,458			$	560,219			$	12,337			$	168,216		$	180,553
	SBA	11,141				364,786				375,927				5,297				39,869			45,166
	Other	68,084				4,336,330				4,404,414				64,279				2,132,109			2,196,388
	Total real estate mortgage	96,986				5,243,574				5,340,560				81,913				2,340,194			2,422,107
	Real estate construction:
	Residential	402				96,326				96,728				750				58,131			58,881
	Commercial	3,346				207,061				210,407				6,291				142,607			148,898
	Total real estate construction	3,748				303,387				307,135				7,041				200,738			207,779
	Commercial:
	Collateralized	22,433				416,754				439,187				18,838				567,643			586,481
	Unsecured	1,323				130,501				131,824				1,856				151,896			153,752
	Asset-based	11,547				1,783,304				1,794,851				6,859				195,569			202,428
	Cash flow	83,321				2,376,530				2,459,851				—				—			—
	Equipment finance	15,973				953,516				969,489				632				272,851			273,483
	SBA	3,207				44,054				47,261				5,761				22,880			28,641
	Total commercial	137,804				5,704,659				5,842,463				33,946				1,210,839			1,244,785
	Consumer	4,073				97,410				101,483				4,411				50,474			54,885
	Total Non-PCI loans and leases	$	242,611			$	11,349,030			$	11,591,641			$	127,311			$	3,802,245		$	3,929,556
Accretable Yield on Purchased Credit Impaired Loans [Table Text Block]	The following table summarizes the accretable yield on the PCI loans acquired in the CapitalSource Inc. merger as of April 7, 2014:
		April 7, 2014
		Accretable Yield
		(In thousands)
	Undiscounted contractual cash flows	$	231,832
	Undiscounted cash flows not expected to be collected (nonaccretable difference)	(138,870		)
	Undiscounted cash flows expected to be collected	92,962
	Estimated fair value of PCI loans acquired	(79,234		)
	Accretable yield	$	13,728
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period	The following table summarizes the changes in the carrying amount of PCI loans and accretable yield on those loans for the years indicated:
		Carrying Amount				Accretable Yield
		(In thousands)
	Balance, December 31, 2011	$	674,058			$	(259,265	)
	Accretion	49,562				49,562
	Payments received	(232,623		)		—
	Decrease in expected cash flows, net	—				13,681
	Negative provision for credit losses	819				—
	Balance, December 31, 2012	491,816				(196,022		)
	Addition from the FCAL acquisition	44,146				(8,096		)
	Accretion	46,680				46,680
	Payments received	(225,849		)		—
	Decrease in expected cash flows, net	—				17,870
	Negative provision for credit losses	4,210				—
	Balance, December 31, 2013	361,003				(139,568		)
	Addition from the CapitalSource merger	79,234				(13,728		)
	Accretion	57,213				57,213
	Payments received	(219,641		)		—
	Increase in expected cash flows, net	—				(10,773		)
	Provision for credit losses	(1,017		)		—
	Balance, December 31, 2014	$	276,792			$	(106,856	)
Non Purchased Credit Impaired Loans and Leases [Domain]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Delinquent loans in loan portfolio	The following tables present an aging analysis of our Non‑PCI loans and leases by portfolio segment and class as of the dates indicated:
		31-Dec-14
		30-89 Days Past Due				90 or More				Total Past Due				Current				Total Loans
						Days Past Due
		(In thousands)
	Real estate mortgage:
	Hospitality	$	—			$	—			$	—			$	560,219			$	560,219
	SBA	5,530				4,357				9,887				366,040				375,927
	Other	6,098				7,630				13,728				4,390,686				4,404,414
	Total real estate mortgage	11,628				11,987				23,615				5,316,945				5,340,560
	Real estate construction:
	Residential	—				—				—				96,728				96,728
	Commercial	—				715				715				209,692				210,407
	Total real estate construction	—				715				715				306,420				307,135
	Commercial:
	Collateralized	878				965				1,843				437,344				439,187
	Unsecured	69				45				114				131,710				131,824
	Asset-based	—				—				—				1,794,851				1,794,851
	Cash flow	—				232				232				2,459,619				2,459,851
	Equipment finance	6,525				366				6,891				962,598				969,489
	SBA	205				1,362				1,567				45,694				47,261
	Total commercial	7,677				2,970				10,647				5,831,816				5,842,463
	Consumer	101				3,146				3,247				98,236				101,483
	Total Non-PCI loans and leases	$	19,406			$	18,818			$	38,224			$	11,553,417			$	11,591,641
		31-Dec-13
		30-89 Days Past Due				90 or More				Total Past Due				Current				Total Loans
						Days Past Due
		(In thousands)
	Real estate mortgage:
	Hospitality	$	—			$	—			$	—			$	180,553			$	180,553
	SBA	2,564				—				2,564				42,602				45,166
	Other	13,026				2,406				15,432				2,180,956				2,196,388
	Total real estate mortgage	15,590				2,406				17,996				2,404,111				2,422,107
	Real estate construction:
	Residential	—				—				—				58,881				58,881
	Commercial	—				2,013				2,013				146,885				148,898
	Total real estate construction	—				2,013				2,013				205,766				207,779
	Commercial:
	Collateralized	473				259				732				585,749				586,481
	Unsecured	83				68				151				153,601				153,752
	Asset-based	—				—				—				202,428				202,428
	Equipment finance	2,662				244				2,906				270,577				273,483
	SBA	1,770				243				2,013				26,628				28,641
	Total commercial	4,988				814				5,802				1,238,983				1,244,785
	Consumer	3,319				—				3,319				51,566				54,885
	Total Non-PCI loans and leases	$	23,897			$	5,233			$	29,130			$	3,900,426			$	3,929,556
Financing Receivable Non Accrual And Performing	The following table presents our nonaccrual and performing Non‑PCI loans and leases by portfolio segment and class as of the dates indicated:
		31-Dec-14												31-Dec-13
		Nonaccrual				Performing				Total				Nonaccrual				Performing			Total
		(In thousands)
	Real estate mortgage:
	Hospitality	$	6,366			$	553,853			$	560,219			$	6,723			$	173,830		$	180,553
	SBA	11,141				364,786				375,927				2,602				42,564			45,166
	Other	20,105				4,384,309				4,404,414				18,648				2,177,740			2,196,388
	Total real estate mortgage	37,612				5,302,948				5,340,560				27,973				2,394,134			2,422,107
	Real estate construction:
	Residential	381				96,347				96,728				389				58,492			58,881
	Commercial	1,178				209,229				210,407				2,830				146,068			148,898
	Total real estate construction	1,559				305,576				307,135				3,219				204,560			207,779
	Commercial:
	Collateralized	5,450				433,737				439,187				9,991				576,490			586,481
	Unsecured	639				131,185				131,824				458				153,294			153,752
	Asset-based	4,574				1,790,277				1,794,851				1,070				201,358			202,428
	Cash flow	15,964				2,443,887				2,459,851				—				—			—
	Equipment finance	11,131				958,358				969,489				632				272,851			273,483
	SBA	3,207				44,054				47,261				3,037				25,604			28,641
	Total commercial	40,965				5,801,498				5,842,463				15,188				1,229,597			1,244,785
	Consumer	3,485				97,998				101,483				394				54,491			54,885
	Total Non-PCI loans and leases	$	83,621			$	11,508,020			$	11,591,641			$	46,774			$	3,882,782		$	3,929,556
Schedule Of Non Accrual and Performing Restructured Impaired Financing Receivables	Non‑PCI nonaccrual loans and leases and performing restructured loans are considered impaired for reporting purposes. The following table presents the composition of our impaired loans and leases as of the dates indicated:
		December 31, 2014												December 31, 2013
						Performing				Total								Performing			Total
		Nonaccrual				Restructured				Impaired				Nonaccrual				Restructured			Impaired
		Loans/Leases				Loans				Loans/Leases				Loans/Leases				Loans			Loans/Leases
		(In thousands)
	Real estate mortgage	$	37,612			$	20,245			$	57,857			$	27,973			$	34,303		$	62,276
	Real estate construction	1,559				8,996				10,555				3,219				4,293			7,512
	Commercial	40,965				5,744				46,709				15,188				2,744			17,932
	Consumer	3,485				259				3,744				394				308			702
	Total	$	83,621			$	35,244			$	118,865			$	46,774			$	41,648		$	88,422
Impaired Financing Receivables, Average Balances And Interest Income Recognized	The following tables present information regarding our Non‑PCI impaired loans and leases by portfolio segment and class as of and for the years indicated:
		31-Dec-14												31-Dec-13
		Recorded Investment				Unpaid Principal Balance				Related				Recorded Investment				Unpaid Principal Balance			Related
										Allowance											Allowance
		(In thousands)
	With An Allowance Recorded:
	Real estate mortgage:
	Hospitality	$	1,946			$	1,945			$	47			$	5,717			$	6,215		$	198
	SBA	—				—				—				1,642				1,643			230
	Other	9,136				9,233				646				15,937				16,571			1,760
	Real estate construction:
	Residential	763				763				46				778				778			168
	Commercial	1,128				4,934				23				1,250				1,250			1
	Commercial:
	Collateralized	4,630				5,246				3,771				4,377				4,692			4,270
	Unsecured	912				924				799				801				829			375
	Asset-based	137				247				137				1,070				1,070			180
	Cash flow	15,578				17,970				2,667				—				—			—
	Equipment finance	6,956				7,268				2,601				—				—			—
	SBA	—				—				—				1,136				1,136			178
	Consumer	143				142				37				424				471			240
	With No Related Allowance Recorded:
	Real estate mortgage:
	Hospitality	$	6,366			$	7,593			$	—			$	3,013			$	3,385		$	—
	SBA	11,141				14,708				—				2,602				3,646			—
	Other	29,268				40,643				—				33,365				46,062			—
	Real estate construction:
	Residential	21				19				—				—				—			—
	Commercial	8,643				8,749				—				5,484				9,923			—
	Commercial:
	Collateralized	5,566				6,877				—				6,700				9,924			—
	Unsecured	725				809				—				179				247			—
	Asset-based	4,436				5,415				—				—				—			—
	Cash flow	387				919				—				—				—			—
	Equipment finance	4,175				7,528				—				632				632			—
	SBA	3,207				4,920				—				3,037				4,945			—
	Consumer	3,601				3,768				—				278				394			—
	Total Non-PCI Loans and Leases With and Without an Allowance Recorded:
	Real estate mortgage	$	57,857			$	74,122			$	693			$	62,276			$	77,522		$	2,188
	Real estate construction	10,555				14,465				69				7,512				11,951			169
	Commercial	46,709				58,123				9,975				17,932				23,475			5,003
	Consumer	3,744				3,910				37				702				865			240
	Total	$	118,865			$	150,620			$	10,774			$	88,422			$	113,813		$	7,600
		Year Ended December 31,
		2014								2013								2012
		Weighted Average				Interest				Weighted Average				Interest				Weighted Average			Interest
		Balance(1)				Income				Balance(1)				Income				Balance(1)			Income
						Recognized								Recognized							Recognized
		(In thousands)
	With An Allowance Recorded:
	Real estate mortgage:
	Hospitality	$	1,946			$	67			$	5,717			$	81			$	8,954		$	80
	SBA	—				—				1,642				90				827			41
	Other	9,136				409				13,205				509				51,441			2,070
	Real estate construction:
	Residential	763				15				778				14				1,303			11
	Commercial	1,027				17				1,250				63				6,723			231
	Commercial:
	Collateralized	4,077				27				3,281				29				2,219			48
	Unsecured	661				21				772				33				2,273			20
	Asset-based	137				—				569				—				—			—
	Cash flow	7,837				—				—				—				—			—
	Equipment finance	3,802				—				—				—				—			—
	SBA	—				—				1,136				56				2,593			53
Consumer	132				8				425				10				389			7
With No Related Allowance Recorded:
Real estate mortgage:
Hospitality	$	6,366			$	—			$	3,013			$	—			$	—		$	—
SBA	6,610				77				2,601				—				1,472			—
Other	21,652				315				27,912				1,060				29,316			1,523
Real estate construction:
Residential	4				—				—				—				—			—
Commercial	8,642				244				4,866				11				17,424			589
Commercial:
Collateralized	2,869				170				3,410				20				1,657			27
Unsecured	126				1				157				—				148			—
Asset-based	3,270				—				—				—				132			—
Cash flow	1				—				—				—				—			—
Equipment finance	2,534				—				245				—				224			—
SBA	2,162				98				2,571				—				2,601			24
Consumer	3,027				2				161				—				136			—
Total Non-PCI Loans and Leases With and Without an Allowance Recorded:
Real estate mortgage	$	45,710			$	868			$	54,090			$	1,740			$	92,010		$	3,714
Real estate construction	10,436				276				6,894				88				25,450			831
Commercial	27,476				317				12,141				138				11,847			172
Consumer	3,159				10				586				10				525			7
Total	$	86,781			$	1,471			$	73,711			$	1,976			$	129,832		$	4,724
_________________________
-1	For the loans and leases (excluding PCI loans) reported as impaired at December 31, 2014, 2013 and 2012, amounts were calculated based on the period of time such loans and leases were impaired during the reported period.
Troubled Debt Restructurings on Financing Receivables	The following table presents new and defaulted troubled debt restructurings of Non-PCI loans for the years indicated:
		Troubled Debt Restructurings											Troubled Debt Restructurings That Subsequently Defaulted(1)
		Number of Loans			Pre- Modification Outstanding Recorded Investment				Post-Modification Outstanding Recorded Investment				Number of Loans			Recorded Investment
		(Dollars In thousands)
	Year Ended December 31, 2014
	Real estate mortgage:
	Hospitality	1			$	1,946			$	1,946			—			$	—
	SBA	1			64				64				1			55
	Other	23			17,443				17,444				—			—
	Real estate construction - Commercial	4			5,507				4,965				—			—
	Commercial:
	Collateralized	22			12,368				6,336				1			390
	Unsecured	10			752				752				—			—
	Equipment finance	1			518				518				—			—
	SBA	3			1,965				1,965				1			1,144
	Consumer	7			467				467				—			—
	Total	72			$	41,030			$	34,457			3			$	1,589		-2
	Year Ended December 31, 2013
	Real estate mortgage - Other	14			$	16,223			$	16,223			2			$	1,844
	Real estate construction - Residential	1			390				390				—			—
	Commercial:
	Collateralized	11			5,618				5,618				1			419
	Unsecured	5			521				521				2			66
	Asset-based	1			2,032				2,032				1			1,070
	SBA	4			137				137				—			—
	Consumer	2			125				125				—			—
	Total	38			$	25,046			$	25,046			6			$	3,399		-3
	Year Ended December 31, 2012
	Real estate mortgage:
	SBA	2			$	1,680			$	1,680			—			$	—
	Other	8			14,861				13,840				—			—
	Real estate construction - Other	3			6,919				6,919				—			—
	Commercial:
	Collateralized	7			1,652				1,652				2			458
	Unsecured	5			317				317				—			—
	SBA	4			1,216				1,216				1			873
	Consumer	1			206				206				—			—
	Total	30			$	26,851			$	25,830			3			$	1,331		-4
	_________________________
	-1	The population of defaulted restructured loans for the period indicated includes only those loans restructured during the preceding 12-month period. The table excludes defaulted troubled restructurings in those classes for which the recorded investment was zero at the end of the period.
	-2	Represents the balance at December 31, 2014, and is net of charge-offs of $129,000.
	-3	Represents the balance at December 31, 2013, and is net of charge-offs of $1.6 million.
	-4	Represents the balance at December 31, 2012, and is net of charge-offs of $921,000.
Purchased Credit Impaired Loans and Leases [Domain]
Accounts, Notes, Loans and Financing Receivable [Line Items]
CV of Loans Held for Investment by class by performing and nonperforming	The following table presents the credit risk rating categories for PCI loans by portfolio segment as of the dates indicated. Nonclassified loans are those with a credit risk rating of either pass or special mention, while classified loans are those with a credit risk rating of either substandard or doubtful.
		31-Dec-14												31-Dec-13
		Nonclassified				Classified				Total				Nonclassified				Classified			Total
		(In thousands)
	Real estate mortgage	$	155,281			$	101,161			$	256,442			$	216,092			$	155,042		$	371,134
	Real estate construction	3,010				3,901				6,911				4,399				6,028			10,427
	Commercial	212				26,942				27,154				569				405			974
	Consumer	—				284				284				—				261			261
	Total PCI loans	$	158,503			$	132,288			$	290,791			$	221,060			$	161,736		$	382,796
Schedule of Accounts, Notes, Loans and Financing Receivable	The following table reflects the PCI loans by portfolio segment as of the dates indicated:
		December 31, 2014				December 31, 2013
		(In thousands)
	Real estate mortgage	$	299,660			$	412,791
	Real estate construction	7,743				12,015
	Commercial	32,904				3,021
	Consumer	332				424
	Total gross PCI loans	340,639				428,251
	Less:
	Discount	(49,848		)		(45,455		)
	Allowance for loan losses	(13,999		)		(21,793		)
	Total net PCI loans	$	276,792			$	361,003

Foreclosed_Assets_Foreclosed_A1

Foreclosed Assets Foreclosed Assets (Tables)	12 Months Ended
	Dec. 31, 2014
Other Real Estate Owned Net Covered and NonCovered Including Foreclosed Assets [Abstract]
Other Real Estate and Foreclosed Assets	The following table summarizes foreclosed assets at the dates indicated:
	Property Type:	31-Dec-14			31-Dec-13
		(In thousands)
	Commercial real estate	$	2,449		$	15,753
	Construction and land development	24,759			35,063
	Multi‑family	4,823			835
	Single family residence	3,392			186
	Total other real estate owned, net	35,423			51,837
	Other foreclosed assets	8,298			4,054
	Total foreclosed assets, net(1)	$	43,721		$	55,891
	_________________________
	-1	As of December 31, 2014 and 2013, the amounts of covered foreclosed assets were $9.3 million and $9.0 million.
Other Foreclosed Assets Rollforward	The following table presents the changes in foreclosed assets, net of the valuation allowance, for the years indicated:
		Year Ended December 31,
		2014			2013			2012
	Foreclosed Assets:	(In thousands)
	Balance, beginning of year	$	55,891		$	56,414		$	81,918
	Addition due to acquisitions	6,382			13,772			1,561
	Foreclosures	9,806			19,470			40,207
	Provision for losses	(7,307		)	(2,515		)	(14,333		)
	Reductions related to sales	(21,051		)	(31,289		)	(53,828		)
	Payments to third parties(1)	—			39			889
	Balance, end of year	$	43,721		$	55,891		$	56,414
	_________________________
	-1	Represents amounts due to participants and for guarantees, property taxes or other prior lien positions.
Foreclosed Assets Valuation Allowance Rollforward	The following table presents the changes in the foreclosed assets valuation allowance for the years indicated:
		Year Ended December 31,
		2014			2013			2012
	Foreclosed Assets Valuation Allowance:	(In thousands)
	Balance, beginning of year	$	11,314		$	16,681		$	20,575
	Provision for losses	7,307			2,515			14,333
	Reductions related to sales	(6,498		)	(7,882		)	(19,103		)
	Selling costs(1)	—			—			876
	Balance, end of year	$	12,123		$	11,314		$	16,681
	_________________________
	-1	During 2011, the FDIC changed its methodology such that selling costs are reimbursed at the time of sale rather than at the time of foreclosure. Such amounts will be realized when the related OREO parcels

FDIC_Loss_Sharing_Asset_FDIC_L1

FDIC Loss Sharing Asset FDIC Loss Sharing Asset (Tables)	12 Months Ended
	Dec. 31, 2014
FDIC Loss-Sharing Arrangements [Abstract]
FDIC Indemnification Asset Roll Forward	The following table presents the changes in the FDIC loss sharing asset for the years indicated:
		Year Ended December 31,
		2014			2013			2012
		(In thousands)
	Balance, beginning of year	$	45,524		$	57,475		$	95,187
	Addition from the FCAL acquisition	—			17,241			—
	FDIC share of additional losses, net of recoveries	(4,941		)	4,969			6,169
	Cash paid to (received from) FDIC	3,202			(7,332		)	(33,223		)
	Net amortization	(25,051		)	(26,829		)	(10,658		)
	Balance, end of year	$	18,734		$	45,524		$	57,475
Schedule of Composition of Loss Sharing Assets and True Up Liability	The following table presents information about the composition of the FDIC loss sharing asset, the true‑up liability, and the non‑single family and the single family covered assets as of the date indicated:
		31-Dec-14
		Affinity Bank			Los Padres Bank			Western Commercial Bank			San Luis Trust Bank		Total
		(In thousands)
	FDIC loss sharing asset	$	(302	)	$	9,435		$	1,165		$	8,436	$	18,734
	True‑up liability	N/A			N/A			$	1,753		$	5,433	$	7,186
	Non-single family covered assets (1)	$	113,361		$	77,814		$	11,327		$	28,555	$	231,057
	Single family covered assets	$	10,987		$	56,891		N/A			$	30,517	$	98,395
	Loss sharing expiration dates:
	Non‑single family	3rd Quarter 2014			3rd Quarter 2015			4th Quarter 2015			1st Quarter 2016
	Single family	3rd Quarter 2019			3rd Quarter 2020			N/A			1st Quarter 2021
	Loss recovery expiration dates:
	Non‑single family	3rd Quarter 2017			3rd Quarter 2018			4th Quarter 2018			1st Quarter 2019
	Single family	3rd Quarter 2019			3rd Quarter 2020			N/A			1st Quarter 2021

Premises_and_Equipment_Net_Pre

Premises and Equipment, Net Premises and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2014
Premises and Equipment, Net [Abstract]
Property, Plant and Equipment	The following table presents the components of premises and equipment as of the dates indicated:
		December 31,
		2014			2013
		(In thousands)
	Land	$	5,505		$	6,755
	Buildings	14,198			12,725
	Furniture, fixtures and equipment	32,359			31,080
	Leasehold improvements	33,157			26,091
	Premises and equipment, gross	85,219			76,651
	Less: accumulated depreciation and amortization	(48,668		)	(44,216		)
	Premises and equipment, net	$	36,551		$	32,435
Schedule of Future Minimum Rental Payments for Operating Leases	We have obligations under a number of noncancelable operating leases for premises and equipment. The following table presents future minimum rental payments under noncancelable operating leases as of December 31, 2014:
	Estimated Lease Payments for Year Ending December 31,	Amount
		(In thousands)
	2015	$	26,767
	2016	22,978
	2017	20,009
	2018	17,293
	2019	13,626
	Thereafter	43,943
	Total	$	144,616

Deposits_Deposits_Tables

Deposits Deposits (Tables)	12 Months Ended
	Dec. 31, 2014
Deposits [Abstract]
Summary of Interest Bearing Deposits	The following table presents the components of interest‑bearing deposits as of the dates indicated:
		December 31,
	Deposit Category	2014		2013
		(In thousands)
	Interest checking deposits	$	736,367	$	620,622
	Money market deposits	1,825,510		1,458,910
	Savings deposits	762,961		218,638
	Time deposits under $100,000	2,467,338		225,360
	Time deposits $100,000 and over	3,031,600		439,011
	Total interest-bearing deposits	$	8,823,776	$	2,962,541
Schedule of Maturities Of Time Deposits	The following table summarizes the maturities of time deposits as of the date indicated:
		31-Dec-14
	Year of Maturity	Time		Time		Total		Rate
		Deposits		Deposits		Time
		Under		$100,000		Deposits
		$100,000		or More
		(Dollars in thousands)
	2015	$	2,233,704	$	2,724,756	4,958,460		0.72	%
	2016	176,125		248,533		424,658		1.01	%
	2017	32,047		36,778		68,825		0.84	%
	2018	20,272		15,067		35,339		1.13	%
	2019	4,880		6,466		11,346		1.03	%
	2020	310		—		310		0.78	%
	Total	$	2,467,338	$	3,031,600	$	5,498,938	0.75	%

Borrowings_and_Subordinated_De1

Borrowings and Subordinated Debentures (Tables)	12 Months Ended
	Dec. 31, 2014
Borrowings Subordinated Debentures And Brokered Deposits [Abstract]
Schedule of Debt	The following table summarizes our borrowings as of the dates indicated:
		December 31, 2014					December 31, 2013
		Amount			Rate		Amount			Rate
		(Dollars in thousands)
	Non‑recourse debt	$	3,402		6.43	%	$	7,126		6.3	%
	FHLB overnight advances	380,000			0.27	%	106,600			0.06	%
	Total borrowings	$	383,402				$	113,726
Borrowings Subordinated Debentures And Brokered Deposits Disclosure	The following table summarizes the terms of each issuance of subordinated debentures outstanding as of the dates indicated:
		31-Dec-14					31-Dec-13
												Date	Maturity	Rate Index
	Series	Amount			Rate (1)		Amount			Rate (2)		Issued	Date	(Quarterly Reset)
		(Dollars in thousands)
	Trust V	$	10,310		3.33	%	$	10,310		3.34	%	8/15/03	9/17/33	3 month LIBOR + 3.10
	Trust VI	10,310			3.29	%	10,310			3.29	%	9/3/03	9/15/33	3 month LIBOR + 3.05
	Trust CII	5,155			3.19	%	5,155			3.19	%	9/17/03	9/17/33	3 month LIBOR + 2.95
	Trust VII	61,856			2.98	%	61,856			2.99	%	2/5/04	4/23/34	3 month LIBOR + 2.75
	Trust CIII	20,619			1.93	%	20,619			1.93	%	8/15/05	9/15/35	3 month LIBOR + 1.69
	Trust FCCI	16,495			1.84	%	16,495			1.84	%	1/25/07	3/15/37	3 month LIBOR + 1.60
	Trust FCBI	10,310			1.79	%	10,310			1.79	%	9/30/05	12/15/35	3 month LIBOR + 1.55
	Trust CS 2005-1 (3)	82,475			2.19	%	—			—		11/21/05	12/15/35	3 month LIBOR + 1.95
	Trust CS 2005-2 (3)	128,866			2.18	%	—			—		12/14/05	1/30/36	3 month LIBOR + 1.95
	Trust CS 2006-1 (3)	51,545			2.18	%	—			—		2/22/06	4/30/36	3 month LIBOR + 1.95
	Trust CS 2006-2 (3)	51,550			2.18	%	—			—		9/27/06	10/30/36	3 month LIBOR + 1.95
	Trust CS 2006-3 (3)(4)	31,188			2.14	%	—			—		9/29/06	10/30/36	3 month EURIBOR + 2.05
	Trust CS 2006-4 (3)	16,470			2.18	%	—			—		12/5/06	1/30/37	3 month LIBOR + 1.95
	Trust CS 2006-5 (3)	6,650			2.18	%	—			—		12/19/06	1/30/37	3 month LIBOR + 1.95
	Trust CS 2007-2 (3)	39,177			2.18	%	—			—		6/13/07	7/30/37	3 month LIBOR + 1.95
	Gross subordinated debentures	542,976					135,055
	Unamortized discount (5)	(109,393		)			(2,410		)
	Net subordinated debentures	$	433,583				$	132,645
	___________________
	-1	As of December 31, 2014.
	-2	As of January 28, 2014.
	-3	Acquired in the CapitalSource Inc. merger.
	-4	Denomination is in Euros with a value of €25.8 million.
	-5	Amount represents the fair value adjustment on trust preferred securities assumed in the CapitalSource Inc. and FCAL acquisitions.

Commitments_and_Contingencies_

Commitments and Contingencies Commitments and Contingencies Disclosure (Tables)	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Commitments Disclosure	The following table presents a summary of the financial instruments described above as of the dates indicated:
		31-Dec-14		31-Dec-13
		(In thousands)
	Loan commitments to extend credit	$	1,921,067	$	1,001,740
	Standby letters of credit	88,495		39,200
	Commitments to purchase equipment being acquired for lease to others	12,839		8,475
		$	2,022,401	$	1,049,415

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Assets and Liabilities Carried at Fair Value on Recurring Basis	The following tables presents information on the assets measured and recorded at fair value on a recurring basis as of the dates indicated:
		Fair Value Measurements as of
		December 31, 2014
	Measured on a Recurring Basis:	Total				Level 1			Level 2			Level 3
		(In thousands)
	Securities available‑for‑sale:
	Government agency and government‑sponsored enterprise
	pass-through securities	$	535,672			$	—		$	535,672		$	—
	Government agency and government‑sponsored enterprise
	collateralized mortgage obligations	277,946				—			277,946			—
	Covered private label CMOs	33,947				—			—			33,947
	Other private label CMOs	10,914				—			10,914			—
	Municipal securities	536,116				—			536,116			—
	Corporate debt securities	110,109				—			110,109			—
	Government‑sponsored enterprise debt securities	36,757				—			36,757			—
	Other securities	25,716				519			25,197			—
	Total securities available-for-sale	1,567,177				519			1,532,711			33,947
	Derivative assets	5,234				—			5,234			—
	Total recurring assets	$	1,572,411			$	519		$	1,537,945		$	33,947
	Derivative liabilities	$	118			$	—		$	118		$	—
		Fair Value Measurements as of
		December 31, 2013
	Measured on a Recurring Basis:	Total				Level 1			Level 2			Level 3
		(In thousands)
	Securities available‑for‑sale:
	Government agency and government‑sponsored enterprise
	pass-through securities	$	707,188			$	—		$	707,188		$	—
	Government agency and government‑sponsored enterprise
	collateralized mortgage obligations	192,873				—			192,873			—
	Covered private label CMOs	37,904				—			—			37,904
	Municipal securities	436,658				—			436,658			—
	Corporate debt securities	82,707				—			82,707			—
	Government‑sponsored enterprise debt securities	9,872				—			9,872			—
	Other securities	27,543				507			27,036			—
	Total recurring assets	$	1,494,745			$	507		$	1,456,334		$	37,904
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques	The following table presents information about quantitative inputs and assumptions used to determine the fair values provided by our third party pricing service for our Level 3 covered private label CMOs measured at fair value on a recurring basis as of December 31, 2014:
			Covered Private Label CMOs
	Unobservable Inputs:		Range of Inputs		Weighted Average Input
	Voluntary annual prepayment speeds		0% - 36.4%		6.30%
	Annual default rates		0% - 38.0%		2.30%
	Loss severity rates		0% - 68.6%		24.00%
	Discount rates		0.2% - 6.7%		4.90%
Fair Value, Assets Measured on Recurring Basis, Significant Unobservable Inputs (Level 3) Reconciliation	The following table summarizes activity for assets measured at fair value on a recurring basis that are categorized as Level 3 for the years indicated:
		Year Ended December 31,
		2014				2013			2012
	Covered Private Label CMOs:	(In thousands)
	Balance, beginning of year	$	37,904			$	44,684		$	45,149
	Total realized in earnings(1)	1,627				1,938			340
	Total unrealized gain (loss) in comprehensive income	(344		)		(1,204		)	4,883
	Net settlements	(5,240		)		(7,514		)	(5,688		)
	Balance, end of year	$	33,947			$	37,904		$	44,684
Assets carried at fair value on a nonrecurring basis	The following tables present assets measured at fair value on a non‑recurring basis as of the dates indicated:
		Fair Value Measurement as of
		December 31, 2014
		Total				Level 1			Level 2			Level 3
	Measured on a Non‑Recurring Basis:	(In thousands)
	Impaired Non‑PCI loans	$	42,693			$	—		$	2,366		$	40,327
	Other real estate owned	24,015				—			18,400			5,615
	Investments carried at cost	566				—			—			566
	Total non-recurring	$	67,274			$	—		$	20,766		$	46,508
		Fair Value Measurement as of
		December 31, 2013
		Total				Level 1			Level 2			Level 3
	Measured on a Non‑Recurring Basis:	(In thousands)
	Impaired Non‑PCI loans	$	40,886			$	—		$	2,051		$	38,835
	Other real estate owned	10,877				—			8,784			2,093
	Total non-recurring	$	51,763			$	—		$	10,835		$	40,928
Net Losses (Gains) on Nonrecurring Assets [Table Text Block]	The following table presents gains and (losses) recognized on assets measured on a nonrecurring basis for the years indicated:
		Year Ended December 31,
		2014				2013			2012
	Gain (Loss) on Assets Measured on a Non‑Recurring Basis:	(In thousands)
	Impaired Non‑PCI loans	$	(7,006	)		$	(1,206	)	$	(5,582	)
	Other real estate owned	(6,737		)		(1,045		)	(3,920		)
	Investments carried at cost	(141		)		—			—
	Total net loss	$	(13,884	)		$	(2,251	)	$	(9,502	)
Fair Value Inputs, Assets, Quantitative Information	The following table presents the valuation methodology and unobservable inputs for Level 3 assets measured at fair value on a nonrecurring basis as of December 31, 2014:
	Asset	Fair Value				Valuation Technique		Unobservable Inputs	Range		Weighted
		(In thousands)									Average
	Impaired Non-PCI loans	$	36,149			Discounted cash flows		Discount rates	0% - 12.17%		5.92%
		4,178				Appraisals		No discounts
	Other real estate owned	5,615				Appraisals		Discount, including selling costs	24% - 38%		35%
	Investments carried at cost	566				Market and Income Approach		Illiquidity Discount	75%		75%
	Total non-recurring Level 3	$	46,508
Fair Value, by Balance Sheet Grouping	The following tables present a summary of the carrying values and estimated fair values of certain financial instruments as of the dates indicated:
		31-Dec-14
		Carrying or				Estimated Fair Value
		Contract
		Amount				Total			Level 1			Level 2		Level 3
		(In thousands)
	Financial Assets:
	Cash and due from banks	$	164,757			$	164,757		$	164,757		$	—	$	—
	Interest‑earning deposits in financial institutions	148,469				148,469			148,469			—		—
	Securities available‑for‑sale	1,567,177				1,567,177			519			1,532,711		33,947
	Investment in FHLB stock	40,609				40,609			—			40,609		—
	Investments carried at cost	3,691				3,691			—			—		3,691
	Investments accounted for under the equity method	21,461				21,700			—			—		21,700
	Loans and leases, net	11,797,977				11,757,951			—			2,366		11,755,585
	Derivative assets	5,234				5,234			—			5,234		—
	Financial Liabilities:
	Deposits:
	Demand, money market, interest checking, and savings deposits	6,256,190				6,256,190			—			6,256,190		—
	Time deposits	5,498,938				5,202,464			—			5,202,464		—
	Borrowings	383,402				383,539			380,000			3,539		—
	Subordinated debentures	433,583				417,657			—			417,657		—
	Derivative liabilities	118				118			—			118		—
		31-Dec-13
		Carrying or				Estimated Fair Value
		Contract
		Amount				Total			Level 1			Level 2		Level 3
		(In thousands)
	Financial Assets:
	Cash and due from banks	$	96,424			$	96,424		$	96,424		$	—	$	—
	Interest‑earning deposits in financial institutions	50,998				50,998			50,998			—		—
	Securities available‑for‑sale	1,494,745				1,494,745			507			1,456,334		37,904
	Investment in FHLB stock	27,939				27,939			—			27,939		—
	Loans and leases, net	4,230,318				4,231,078			—			2,051		4,229,027
	Financial Liabilities:
	Deposits:
	Demand, money market, interest checking, and savings deposits	4,616,616				4,616,616			—			4,616,616		—
	Time deposits	664,371				665,148			—			665,148		—
	Borrowings	113,726				113,726			106,600			7,126		—
	Subordinated debentures	132,645				132,498			—			132,498		—

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit)	The following table presents the components of income tax expense for the years indicated:
		December 31,
		2014			2013			2012
		(In thousands)
	Current Income Tax Expense:
	Federal	$	(11,459	)	$	(29,591	)	$	(24,177	)
	State	(10,823		)	(7,667		)	(1,825		)
	Total current income tax expense	(22,282		)	(37,258		)	(26,002		)
	Deferred Income Tax (Expense) Benefit:
	Federal	(70,662		)	9,099			(2,550		)
	State	(19,795		)	(1,586		)	(8,143		)
	Total deferred income tax (expense) benefit	(90,457		)	7,513			(10,693		)
	Total income tax expense	$	(112,739	)	$	(29,745	)	$	(36,695	)
Schedule of Effective Income Tax Rate Reconciliation	The following table presents a reconciliation of the recorded income tax expense to the amount of taxes computed by applying the applicable federal statutory income tax rate of 35% to earnings or loss before income taxes for the years indicated:
		December 31,
		2014			2013			2012
		(In thousands)
	Computed expected income tax expense at federal statutory rate	$	(98,575	)	$	(26,201	)	$	(32,724	)
	State tax expense, net of federal tax benefit	(15,689		)	(6,014		)	(6,479		)
	Tax‑exempt interest benefit	4,472			3,979			1,847
	Increase in cash surrender value of life insurance	739			407			442
	Tax credits	3,567			2,480			1,313
	Nondeductible employee compensation	(6,792		)	(4,730		)	(322		)
	Nondeductible acquisition‑related expense	(2,994		)	(1,196		)	(532		)
	Acquisition‑related securities gain	—			1,828			—
	Other, net	2,533			(298		)	(240		)
	Recorded income tax expense	$	(112,739	)	$	(29,745	)	$	(36,695	)
Schedule of Deferred Tax Assets and Liabilities	The following table presents the tax effects of temporary differences that give rise to significant portions of deferred tax assets and deferred tax liabilities as of the dates indicated:
		December 31,
		2014			2013
		(In thousands)
	Deferred Tax Assets:
	Book allowance for loan losses in excess of tax specific charge-offs	$	100,981		$	45,840
	Interest on nonaccrual loans	7,394			444
	Deferred compensation	4,585			4,541
	Premises and equipment, principally due to differences in depreciation	5,359			3,643
	Foreclosed assets valuation allowance	7,353			9,784
	Assets acquired in FDIC‑assisted acquisition	10,217			16,375
	State tax benefit	5,009			2,368
	Net operating losses	207,575			197
	Capital loss carryforwards	57,494			—
	Accrued liabilities	36,115			16,629
	Other	6,254			8,084
	Equity Investments	8,666			568
	Goodwill	44,372			6,595
	Deferred loan fees and costs	—			378
	Tax credits	32,183			—
	Unrealized loss on securities available‑for‑sale	—			2,424
	Gross deferred tax assets	533,557			117,870
	Valuation Allowance	(130,282		)	—
	Deferred tax assets, net of valuation allowance	403,275			117,870
	Deferred Tax Liabilities:
	Core deposit and customer relationship intangibles	3,978			6,022
	Deferred loan fees and costs	17,594			—
	Unrealized gain on securities available‑for‑sale	17,926			—
	FHLB stock	2,820			7,123
	Subordinated debentures	40,369			1,003
	Operating Leases	34,136			—
	Unrealized income from FDIC‑assisted acquisition	2,041			24,086
	Gross deferred tax liabilities	118,864			38,234
	Total net deferred tax asset	$	284,411		$	79,636
Schedule of Unrecognized Tax Benefits Roll Forward	The schedule below details the activities during 2014.
		Unrecognized
		Tax Benefits
		(In thousands)
	Balance, December 31, 2013	$	—
	Increase related to CapitalSource Inc. merger	18,724
	Increase based on tax positions related to prior years	2,371
	Reductions related to settlements	(293		)
	Reductions for tax positions as a result of a lapse of the applicable statute of limitations	(301		)
	Balance, December 31, 2014	$	20,501

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Net Income Per Share	The following table presents the computation of basic and diluted net earnings per share for the years indicated:
		Year Ended December 31,
		2014			2013			2012
		(Dollars in thousands, except per share data)
	Basic earnings per share:
	Net earnings from continuing operations	$	170,468		$	45,477		$	56,801
	Less: earnings allocated to unvested restricted stock(1)	(1,959		)	(1,096		)	(1,845		)
	Net earnings from continuing operations allocated to common shares	168,509			44,381			54,956
	Net (loss) earnings from discontinued operations allocated to common shares	(1,545		)	(348		)	—
	Net earnings allocated to common shares	$	166,964		$	44,033		$	54,956
	Weighted-average basic shares and unvested restricted stock outstanding	87,871			42,506			37,370
	Less: weighted-average unvested restricted stock outstanding	(1,018		)	(1,683		)	(1,685		)
	Weighted-average basic shares outstanding	86,853			40,823			35,685
	Basic earnings per share:
	Net earnings from continuing operations	$	1.94		$	1.09		$	1.54
	Net loss from discontinued operations	(0.02		)	(0.01		)	—
	Net earnings	$	1.92		$	1.08		$	1.54
	Diluted earnings per share:
	Net earnings from continuing operations allocated to common shares	$	168,509		$	44,381		$	54,956
	Net (loss) earnings from discontinued operations allocated to common shares	(1,545		)	(348		)	—
	Net earnings allocated to common shares	$	166,964		$	44,033		$	54,956
	Weighted-average basic shares outstanding	86,853			40,823			35,685
	Diluted earnings per share:
	Net earnings from continuing operations	$	1.94		$	1.09		$	1.54
	Net loss from discontinued operations	(0.02		)	(0.01		)	—
	Net earnings	$	1.92		$	1.08		$	1.54
	________________________
	-1	Represents cash dividends paid to holders of unvested restricted stock, net of estimated forfeitures, plus undistributed earnings amounts available to holders of unvested restricted stock, if any.

Stock_Based_Compensation_Plan_

Stock Based Compensation Plan Stock-based Compensation Plan (Tables)	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]	The following table presents a summary of restricted stock transactions for the years indicated:
		Number of		Weighted Average
		Shares		Grant Date Fair Value
				(Per Share)
	Unvested restricted stock, December 31, 2011	1,675,730		$	30.53
	Granted	226,400		23.77
	Shares issued by the Company upon vesting	(195,871	)	21.69
	Forfeited	(7,978	)	22.31
	Unvested restricted stock, December 31, 2012	1,698,281		30.68
	Granted	673,900		29.06
	Shares issued by the Company upon vesting	(819,461	)	24.84
	Forfeited	(336,196	)	48.92
	Unvested restricted stock, December 31, 2013	1,216,524		28.69
	Granted	1,129,805		40.37
	Shares issued by the Company upon vesting	(1,183,024	)	28.53
	Forfeited	(54,800	)	38.97
	Unvested restricted stock, December 31, 2014	1,108,505		$	40.37
Schedule of Share-based Compensation Arrangement by Share-based Payment Award, Restricted Stock Units, Vested and Expected to Vest [Table Text Block]	The following table summarizes information about outstanding time-based restricted stock awards as of the date indicated:
		December 31, 2014
				Weighted				Weighted
				Average		Weighted		Average
		Number		Grant Date		Average		Remaining
		of Shares		Fair Value		Fair Value(1)		Contractual
		Outstanding		(Per Share)		(In thousands)		Life (Years)
	Time-based restricted stock granted in:
	2013	27,000		$	35.08	$	1,228	1.6
	2014	1,081,505		$	40.37	49,165		1.6
	Outstanding time-based restricted stock awards	1,108,505		$	40.37	$	50,393	1.6
	_________________________
	-1	Determined using the $45.46 closing price of PacWest common stock on December 31, 2014.

Dividend_Availability_and_Regu1

Dividend Availability and Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2014
Dividend Availability and Regulatory Matters [Abstract]
Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations	The following table presents actual capital amounts and ratios for the Company and the Bank as of the dates indicated:
		Actual			Well Capitalized			Excess
					Minimum			Capital
					Requirement
		Amount	Ratio		Amount	Ratio		Amount
		(Dollars in thousands)
	31-Dec-14
	Tier I capital (to average assets):
	PacWest Bancorp Consolidated	1,722,870	12.34	%	698,109	5	%	1,024,761
	Pacific Western Bank	1,621,546	11.7	%	693,174	5	%	928,372
	Tier I capital (to risk‑weighted assets):
	PacWest Bancorp Consolidated	1,722,870	13.16	%	785,781	6	%	937,089
	Pacific Western Bank	1,621,546	12.46	%	780,834	6	%	840,712
	Total capital (to risk‑weighted assets):
	PacWest Bancorp Consolidated	2,104,984	16.07	%	1,309,635	10	%	795,349
	Pacific Western Bank	1,712,312	13.16	%	1,301,390	10	%	410,922
	31-Dec-13
	Tier I capital (to average assets):
	PacWest Bancorp Consolidated	718,800	11.22	%	320,405	5	%	398,395
	Pacific Western Bank	690,440	10.79	%	319,999	5	%	370,441
	Tier I capital (to risk‑weighted assets):
	PacWest Bancorp Consolidated	718,800	15.12	%	285,163	6	%	433,637
	Pacific Western Bank	690,440	14.54	%	284,825	6	%	405,615
	Total capital (to risk‑weighted assets):
	PacWest Bancorp Consolidated	778,582	16.38	%	475,271	10	%	303,311
	Pacific Western Bank	750,152	15.8	%	474,708	10	%	275,444

Business_Segment_Tables

Business Segment (Tables)	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Reconciliation of Assets from Segment to Consolidated [Table Text Block]	The following tables present information regarding our business segments as of and for the years indicated:
		31-Dec-14
		Community			National						Consolidated
	Balance Sheet Data:	Banking			Lending			Other			Company
		(In thousands)
	Loans and leases, net of unearned income	$	3,401,129		$	8,455,849		$	25,454		$	11,882,432
	Allowance for loan and lease losses	(48,253		)	(36,202		)	—			(84,455		)
	Total loans and leases, net	$	3,352,876		$	8,419,647		$	25,454		$	11,797,977
	Goodwill(1)	$	326,078		$	1,394,401		$	—		$	1,720,479
	Core deposit and customer relationship intangibles, net	16,306			898			—			17,204
	Total assets	6,512,313			9,483,601			238,886			16,234,800
	Total deposits(2)	12,030,436			33,179			(308,487		)	11,755,128
	________________________
	-1	The increase in the goodwill for the Community Banking segment and National Lending segment during 2014 was due primarily to $1.5 billion from the CapitalSource merger.
	-2	The negative balance for total deposits in the “Other” segment represents the elimination of holding company cash held in deposit accounts at the Bank.
		31-Dec-13
		Community			National						Consolidated
	Balance Sheet Data:	Banking			Lending			Other			Company
		(In thousands)
	Loans and leases, net of unearned income	$	3,837,475		$	474,877		$	—		$	4,312,352
	Allowance for loan and lease losses	(75,498		)	(6,536		)	—			(82,034		)
	Total loans and leases, net	$	3,761,977		$	468,341		$	—		$	4,230,318
	Goodwill(1)	$	183,065		$	25,678		$	—		$	208,743
	Core deposit and customer relationship intangibles, net	15,331			1,917			—			17,248
	Total assets	6,004,067			519,675			9,621			6,533,363
	Total deposits(2)	5,302,822			—			(21,835		)	5,280,987
	________________________
	-1	The increase in the Community Banking segment's goodwill during 2013 was due primarily to $129.1 million from the FCAL acquisition.
	-2	The negative balance for total deposits in the “Other” segment represents the elimination of holding company cash held in deposit accounts at the Bank.
Continuing operations of operating segments
		Year Ended December 31, 2014
		Community			National						Consolidated
	Results of Operations:	Banking			Lending			Other			Company
		(In thousands)
	Interest income	$	279,671		$	422,677		$	2,427		$	704,775
	Interest expense	(27,598		)	(230		)	(14,570		)	(42,398		)
	Intersegment interest income (expense)	15,716			(15,716		)	—			—
	Net interest income (expense)	267,789			406,731			(12,143		)	662,377
	Negative provision (provision) for credit losses	21,311			(32,810		)	—			(11,499		)
	Gain on securities	4,841			—			—			4,841
	FDIC loss sharing expense	(31,730		)	—			—			(31,730		)
	Other noninterest income	25,168			34,215			9,693			69,076
	Total noninterest income	(1,721		)	34,215			9,693			42,187
	Foreclosed assets (expense) income, net	(5,685		)	(302		)	586			(5,401		)
	Intangible asset amortization	(5,745		)	(523		)	—			(6,268		)
	Acquisition, integration and reorganization costs	(89,888		)	(10,073		)	(1,055		)	(101,016		)
	Other noninterest expense	(198,921		)	(80,418		)	(16,720		)	(296,059		)
	Total noninterest expense	(300,239		)	(91,316		)	(17,189		)	(408,744		)
	Intersegment noninterest income (expense)	71,897			(71,897		)	—			—
	Total noninterest expense - adjusted	(228,342		)	(163,213		)	(17,189		)	(408,744		)
	Earnings from continuing operations before taxes	59,037			244,923			(19,639		)	284,321
	Income tax (expense) benefit	(27,370		)	(97,853		)	11,370			(113,853		)
	Net earnings (loss) from continuing operations	31,667			147,070			(8,269		)	170,468
	Loss from discontinued operations before taxes	(2,677		)	—			—			(2,677		)
	Income tax benefit	1,114			—			—			1,114
	Net loss from discontinued operations	(1,563		)	—			—			(1,563		)
	Net earnings (loss)	$	30,104		$	147,070		$	(8,269	)	$	168,905
		Year Ended December 31, 2013
		Community			National						Consolidated
	Results of Operations:	Banking			Lending			Other			Company
		(In thousands)
	Interest income	$	261,492		$	48,422		$	—		$	309,914
	Interest expense	(7,873		)	(532		)	(3,796		)	(12,201		)
	Intersegment interest income (expense)	1,525			(1,525		)	—			—
	Net interest income	255,144			46,365			(3,796		)	297,713
	Negative provision (provision) for credit losses	8,079			(3,869		)	—			4,210
	Gain on securities	137			—			5,222			5,359
	FDIC loss sharing expense	(26,172		)	—			—			(26,172		)
	Other noninterest income	21,395			3,558			104			25,057
	Total noninterest income	(4,640		)	3,558			5,326			4,244
	Foreclosed assets income, net	1,503			—			—			1,503
	Intangible asset amortization	(4,748		)	(654		)	—			(5,402		)
	Acquisition, integration and reorganization costs	(40,552		)	—			(260		)	(40,812		)
	Other noninterest expense	(156,600		)	(23,575		)	(5,801		)	(185,976		)
	Total noninterest expense	(200,397		)	(24,229		)	(6,061		)	(230,687		)
	Earnings (loss) from continuing operations before taxes	58,186			21,825			(4,531		)	75,480
	Income tax (expense) benefit	(24,940		)	(9,101		)	4,038			(30,003		)
	Net earnings from continuing operations	33,246			12,724			(493		)	45,477
	Loss from discontinued operations before taxes	(620		)	—			—			(620		)
	Income tax benefit	258			—			—			258
	Net loss from discontinued operations	(362		)	—			—			(362		)
	Net earnings (loss)	$	32,884		$	12,724		$	(493	)	$	45,115
		Year Ended December 31, 2012
		Community			National						Consolidated
	Results of Operations:	Banking			Lending			Other			Company
		(In thousands)
	Interest income	$	251,720		$	44,395		$	—		$	296,115
	Interest expense	(15,043		)	(884		)	(3,721		)	(19,648		)
	Intersegment interest income (expense)	2,055			(2,055		)	—			—
	Net interest income	238,732			41,456			(3,721		)	276,467
	Negative provision (provision) for credit losses	14,585			(1,766		)	—			12,819
	Gain on securities	1,239			—			—			1,239
	FDIC loss sharing expense	(10,070		)	—			—			(10,070		)
Other noninterest income	20,572			4,017			114			24,703
Total noninterest income	11,741			4,017			114			15,872
Foreclosed assets expense, net	(10,931		)	—			—			(10,931		)
Intangible asset amortization	(5,898		)	(428		)	—			(6,326		)
Acquisition, integration and reorganization costs	(4,089		)	—			—			(4,089		)
Debt termination expense	(24,195		)	—			1,597			(22,598		)
Other noninterest expense	(138,640		)	(23,502		)	(5,576		)	(167,718		)
Total noninterest expense	(183,753		)	(23,930		)	(3,979		)	(211,662		)
Earnings (loss) before taxes	81,305			19,777			(7,586		)	93,496
Income tax (expense) benefit	(31,542		)	(8,327		)	3,174			(36,695		)
Net earnings (loss)	$	49,763		$	11,450		$	(4,412	)	$	56,801

Condensed_Financial_Informatio1

Condensed Financial Information Of Parent Company (Tables)	12 Months Ended
	Dec. 31, 2014
Condensed Financial Information Of Parent Company [Abstract]
Condensed Balance Sheet
	Parent Company Only	December 31,
	Condensed Balance Sheets	2014			2013
		(In thousands)
	Assets:
	Cash and due from banks	$	309,220		$	21,835
	Investments in subsidiaries	3,119,642			911,200
	Other assets	212,157			10,341
	Total assets	$	3,641,019		$	943,376
	Liabilities:
	Subordinated debentures	$	133,232		$	132,645
	Other liabilities	1,362			1,638
	Total liabilities	134,594			134,283
	Stockholders’ equity	3,506,425			809,093
	Total liabilities and stockholders’ equity	$	3,641,019		$	943,376
Condensed Income Statement
	Parent Company Only	December 31,
	Condensed Statement of Earnings	2014			2013			2012
		(In thousands)
	Miscellaneous income	$	122		$	104		$	114
	Acquisition‑related securities gain	—			5,222			—
	Debt termination income	—			—			1,597
	Dividends from Bank subsidiary	137,000			48,000			50,000
	Total income	137,122			53,326			51,711
	Interest expense	4,211			3,796			3,721
	Operating expenses	8,105			6,061			5,576
	Total expenses	12,316			9,857			9,297
	Earnings before income taxes and equity in undistributed earnings of subsidiaries	124,806			43,469			42,414
	Income tax benefit	5,164			4,038			3,174
	Earnings before equity in undistributed earnings of subsidiaries	129,970			47,507			45,588
	Equity in undistributed earnings of subsidiaries	38,935			(2,392		)	11,213
	Net earnings	$	168,905		$	45,115		$	56,801
Condensed Cash Flow Statement
	Parent Company Only	December 31,
	Condensed Statements of Cash Flows	2014			2013			2012
		(In thousands)
	Cash flows from operating activities:
	Net earnings	$	168,905		$	45,115		$	56,801
	Adjustments to reconcile net earnings to net cash provided by operating activities:
	Acquisition‑related securities gain	—			(5,222		)	—
	Change in other assets	39,874			(609		)	711
	Change in liabilities	310			4,932			(4,122		)
	Tax effect in stockholders’ equity of restricted stock vesting	4,625			(364		)	(102		)
	Earned stock compensation	41,099			441			715
	Equity in undistributed (earnings) losses of subsidiaries	(38,935		)	2,392			(11,213		)
	Net cash provided by operating activities	215,878			46,685			42,790
	Cash flows from investing activities:
	Net cash and cash equivalents acquired in acquisition	226,960			857			—
	Purchases of securities available‑for‑sale	—			—			(1,500		)
	Net cash provided by (used in) investing activities	226,960			857			(1,500		)
	Cash flows from financing activities:
	Redemptions of subordinated debentures	—			—			(18,558		)
	Tax effect in stockholders’ equity of restricted stock vesting	(4,625		)	364			102
	Restricted stock surrendered	(22,307		)	(13,537		)	(1,475		)
	Cash dividends paid, net	(114,162		)	(41,006		)	(28,787		)
	Net cash used in financing activities	(141,094		)	(54,179		)	(48,718		)
	Net increase (decrease) in cash and cash equivalents	301,744			(6,637		)	(7,428		)
	Cash and cash equivalents, beginning of year	21,835			28,472			35,900
	Cash and cash equivalents, end of year	$	323,579		$	21,835		$	28,472
	Supplemental disclosure of noncash investing and financing activities:
	Common stock issued for acquisitions	$	2,594,070		$	242,268		$	—

Selected_Quarterly_Financial_D1

Selected Quarterly Financial Data Selected Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	The following tables set forth our unaudited quarterly results for the periods indicated:
		Three Months Ended
		December 31,			September 30,			June 30,			March 31,
		2014			2014			2014			2014
		(Dollars in thousands, except per share data)
	Interest income	$	209,696		$	202,356		$	204,363		$	88,360
	Interest expense	(14,713		)	(13,510		)	(11,830		)	(2,345		)
	Net interest income	194,983			188,846			192,533			86,015
	(Provision) negative provision for credit losses	(2,063		)	(5,050		)	(5,030		)	644
	FDIC loss sharing expense, net	(4,360		)	(7,415		)	(8,525		)	(11,430		)
	Gain on securities	—			—			89			4,752
	Other noninterest income	17,063			23,729			16,915			11,369
	Total noninterest income	12,703			16,314			8,479			4,691
	Foreclosed assets (expense) income, net	(1,938		)	(4,827		)	(497		)	1,861
	Acquisition, integration and reorganization costs	(7,381		)	(5,193		)	(86,242		)	(2,200		)
	Other noninterest expense	(83,021		)	(85,609		)	(83,167		)	(50,530		)
	Total noninterest expense	(92,340		)	(95,629		)	(169,906		)	(50,869		)
	Earnings from continuing operations before income taxes	113,283			104,481			26,076			40,481
	Income tax expense	(42,226		)	(42,205		)	(14,846		)	(14,576		)
	Net earnings from continuing operations	71,057			62,276			11,230			25,905
	Loss from discontinued operations before income taxes	(105		)	(8		)	(1,151		)	(1,413		)
	Income tax benefit	47			3			476			588
	Net loss from discontinued operations	(58		)	(5		)	(675		)	(825		)
	Net earnings	$	70,999		$	62,271		$	10,555		$	25,080
	Basic earnings per share:
	Net earnings from continuing operations	$	0.69		$	0.6		$	0.11		$	0.57
	Net earnings	$	0.69		$	0.6		$	0.1		$	0.55
	Diluted earnings per share:
	Net earnings from continuing operations	$	0.69		$	0.6		$	0.11		$	0.57
	Net earnings	$	0.69		$	0.6		$	0.1		$	0.55
		Three Months Ended
		December 31,			September 30,			June 30,			March 31,
		2013			2013			2013			2013
		(Dollars in thousands, except per share data)
	Interest income	$	83,856		$	85,158		$	71,631		$	69,269
	Interest expense	(2,598		)	(2,869		)	(3,158		)	(3,576		)
	Net interest income	81,258			82,289			68,473			65,693
	Negative provision (provision) for credit losses	1,338			4,167			1,842			(3,137		)
	FDIC loss sharing expense, net	(10,593		)	(7,032		)	(5,410		)	(3,137		)
	(Loss) gain on securities	(272		)	5,222			—			409
	Other noninterest income	6,939			6,937			5,613			5,568
	Total noninterest income	(3,926		)	5,127			203			2,840
	Foreclosed assets income, net	569			420			14			500
	Acquisition, integration and reorganization costs	(16,673		)	(5,450		)	(17,997		)	(692		)
	Other noninterest expense	(49,984		)	(51,170		)	(46,233		)	(43,991		)
	Total noninterest expense	(66,088		)	(56,200		)	(64,216		)	(44,183		)
	Earnings from continuing operations before income taxes	12,582			35,383			6,302			21,213
	Income tax expense	(9,135		)	(11,243		)	(1,906		)	(7,719		)
	Net earnings from continuing operations	3,447			24,140			4,396			13,494
	(Loss) earnings from discontinued operations before income taxes	(578		)	39			(81		)	—
	Income tax benefit (expense)	240			(16		)	34			—
	Net (loss) earnings from discontinued operations	(338		)	23			(47		)	—
	Net earnings	$	3,109		$	24,163		$	4,349		$	13,494
	Basic earnings per share:
	Net earnings from continuing operations	$	0.07		$	0.53		$	0.11		$	0.37
	Net earnings	$	0.06		$	0.53		$	0.11		$	0.37
	Diluted earnings per share:
	Net earnings from continuing operations	$	0.07		$	0.53		$	0.11		$	0.37
	Net earnings	$	0.06		$	0.53		$	0.11		$	0.37

Organization_Details

Organization (Details) (USD $)	12 Months Ended		0 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Apr. 07, 2014	31-May-13	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
	bank_branch
Business Acquisition [Line Items]
Total assets	$16,234,800				$6,533,363
Accounting Policies [Abstract]
Total loans and leases, net	11,797,977				4,230,318
Total deposits	11,755,128	[1]			5,280,987	[1]
Total stockholders' equity	$3,506,425				$809,093		$589,121	$546,203
Number Of Branches	80
Number of Businesses Acquired	27
Capitalsource, Inc. [Member]
Accounting Policies [Abstract]
Business Acquisition, Effective Date of Acquisition	7-Apr-14		7-Apr-14
First California Financial Group, Inc. [Member]
Accounting Policies [Abstract]
Business Acquisition, Effective Date of Acquisition				31-May-13
[1]	(2)The negative balance for total deposits in the “Other” segment represents the elimination of holding company cash held in deposit accounts at the Bank.

Organization_FDIC_Loss_Share_A

Organization FDIC Loss Share Agreements (Details) (USD $)	3 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2014
Schedule of FDIC Loss Sharing Asset [Line Items]
Date of asset-based lending companies reorganization & sale of Celtic Corporation	1-Jul-14
Affinity Bank [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
Threshold of covered assets per FDIC loss-share agreement		234
Affinity Bank [Member] | Below threshold [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
FDIC Indemnification rate on covered assets		80.00%
Recovery rate of assuming bank on covered assets		80.00%
Affinity Bank [Member] | Above threshold [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
FDIC Indemnification rate on covered assets		95.00%
Recovery rate of assuming bank on covered assets		95.00%
Affinity Bank [Member] | Commercial Real Estate [Member] | FDIC indemnification provision under loss share arrangement [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
Expiration date of provision		30-Sep-14
Affinity Bank [Member] | Commercial Real Estate [Member] | Recovery provision for assuming bank under FDIC loss-share agreement [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
Expiration date of provision		30-Sep-17
Affinity Bank [Member] | Residential Mortgage [Member] | FDIC indemnification provision under loss share arrangement [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
Expiration date of provision		30-Sep-19
Affinity Bank [Member] | Residential Mortgage [Member] | Recovery provision for assuming bank under FDIC loss-share agreement [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
Expiration date of provision		30-Sep-19
Los Padres Bank [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
FDIC Indemnification rate on covered assets		80.00%
Recovery rate of assuming bank on covered assets		80.00%
Los Padres Bank [Member] | Commercial Real Estate [Member] | FDIC indemnification provision under loss share arrangement [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
Expiration date of provision		30-Sep-15
Los Padres Bank [Member] | Commercial Real Estate [Member] | Recovery provision for assuming bank under FDIC loss-share agreement [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
Expiration date of provision		30-Sep-18
Los Padres Bank [Member] | Residential Mortgage [Member] | FDIC indemnification provision under loss share arrangement [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
Expiration date of provision		30-Sep-20
Los Padres Bank [Member] | Residential Mortgage [Member] | Recovery provision for assuming bank under FDIC loss-share agreement [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
Expiration date of provision		30-Sep-20
Western Commercial Bank [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
FDIC Indemnification rate on covered assets		80.00%
Recovery rate of assuming bank on covered assets		80.00%
Western Commercial Bank [Member] | Commercial Real Estate [Member] | FDIC indemnification provision under loss share arrangement [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
Expiration date of provision		31-Dec-15
Western Commercial Bank [Member] | Commercial Real Estate [Member] | Recovery provision for assuming bank under FDIC loss-share agreement [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
Expiration date of provision		31-Dec-18
San Luis Trust Bank [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
FDIC Indemnification rate on covered assets		80.00%
Recovery rate of assuming bank on covered assets		80.00%
San Luis Trust Bank [Member] | Commercial Real Estate [Member] | FDIC indemnification provision under loss share arrangement [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
Expiration date of provision		31-Mar-16
San Luis Trust Bank [Member] | Commercial Real Estate [Member] | Recovery provision for assuming bank under FDIC loss-share agreement [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
Expiration date of provision		31-Mar-19
San Luis Trust Bank [Member] | Residential Mortgage [Member] | FDIC indemnification provision under loss share arrangement [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
Expiration date of provision		31-Mar-21
San Luis Trust Bank [Member] | Residential Mortgage [Member] | Recovery provision for assuming bank under FDIC loss-share agreement [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
Expiration date of provision		31-Mar-21

Organization_Derivatives_Detai

Organization Derivatives Details (Details) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair Value Hedges, Net	$0
Derivative, Notional Amount	$67.80

Discontinued_Operations_Detail

Discontinued Operations (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 Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss from discontinued operations before taxes	($105,000)	($8,000)	($1,151,000)	($1,413,000)	($578,000)	$39,000	($81,000)	$0	($2,677,000)	($620,000)	$0
Liabilities	12,728,375,000				5,724,270,000				12,728,375,000	5,724,270,000
Electronic Payment Systems [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue									0	2,600,000
Liabilities	$21,300,000				$123,000,000				$21,300,000	$123,000,000

Restricted_Cash_Details

Restricted Cash (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Restricted Cash Balances [Abstract]
Restricted Cash and Cash Equivalents	$10	$13.10

Acquisitions_Details

Acquisitions (Details) (USD $)	12 Months Ended					0 Months Ended									1 Months Ended	0 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012	Aug. 01, 2012	Aug. 01, 2012	Apr. 03, 2012	Apr. 03, 2012	Apr. 07, 2014		Apr. 07, 2014		31-May-13	31-May-13	Jan. 03, 2012	Jan. 03, 2012	Dec. 31, 2011
Business Acquisition [Line Items]
Equipment leased to others under operating leases	$122,506		$0
Goodwill	1,720,479	[1]	208,743	[1]	79,866													39,141
Collection of securities sales proceeds	484,084		0		0
American Perspective Bank [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition						1-Aug-12
Cash and due from banks						3,370	3,370
Interest-earning deposits in financial institutions						10,081	10,081
Investments securities available-for-sale						48,887	48,887
FHLB stock						1,412	1,412
Loans and leases						197,279	197,279
Equipment leased to others under operating leases						0	0
Premises and equipment						0	0
Foreclosed Assets						1,561	1,561
FDIC loss sharing asset						0	0
Income Tax Assets						2,194	2,194
Goodwill						15,047	15,047
Other intangible assets						1,924	1,924
Leases In Process						0	0
Other assets						2,040	2,040
Total assets acquired						283,795	283,795
Noninterest-bearing deposits						40,673	40,673
Interest-bearing deposits						178,891	178,891
Other borrowings						5,315	5,315
Borrowings from Parent						0	0
Subordinated Debentures						0	0
Discontinued operations						0	0
Accrued interest payable and other liabilities						840	840
Total liabilities assumed						225,719	225,719
Total consideration paid						58,076	58,076
Cash paid						58,076
PacWest common stock issued						0
Cancellation of FCAL common stock owned by PacWest (at acquisition date fair value)						0	0
Celtic Capital Corporation [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition								3-Apr-12
Cash and due from banks								3,435	3,435
Interest-earning deposits in financial institutions								0	0
Investments securities available-for-sale								0	0
FHLB stock								0	0
Loans and leases								54,963	54,963
Equipment leased to others under operating leases								0	0
Premises and equipment								0	0
Foreclosed Assets								0	0
FDIC loss sharing asset								0	0
Income Tax Assets								19	19
Goodwill								6,645	6,645
Other intangible assets								1,300	1,300
Leases In Process								0	0
Other assets								720	720
Total assets acquired								67,082	67,082
Noninterest-bearing deposits								0	0
Interest-bearing deposits								0	0
Other borrowings								46,804	46,804
Borrowings from Parent								0	0
Subordinated Debentures								0	0
Discontinued operations								0	0
Accrued interest payable and other liabilities								2,278	2,278
Total liabilities assumed								49,082	49,082
Total consideration paid								18,000	18,000
Cash paid								18,000
PacWest common stock issued								0
Cancellation of FCAL common stock owned by PacWest (at acquisition date fair value)								0	0
Capitalsource, Inc. [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition	7-Apr-14											7-Apr-14
Cash and due from banks										768,553		768,553
Interest-earning deposits in financial institutions										60,612		60,612
Investments securities available-for-sale										382,797		382,797
FHLB stock										46,060		46,060
Loans and leases										6,877,427		6,877,427
Equipment leased to others under operating leases										160,015		160,015
Premises and equipment										12,663		12,663
Foreclosed Assets										6,382		6,382
FDIC loss sharing asset										0		0
Income Tax Assets										312,757		312,757
Goodwill										1,518,381		1,518,381
Other intangible assets										6,720		6,720
Leases In Process										0		0
Other assets										582,985	[2]	582,985	[2]
Total assets acquired										10,735,352		10,735,352
Noninterest-bearing deposits										4,631		4,631
Interest-bearing deposits										6,236,419		6,236,419
Other borrowings										992,109		992,109
Borrowings from Parent										0		0
Subordinated Debentures										300,918		300,918
Discontinued operations										0		0
Accrued interest payable and other liabilities										124,087		124,087
Total liabilities assumed										7,658,164		7,658,164
Total consideration paid										3,077,188		3,077,188
Cash paid										483,118
PacWest common stock issued										2,594,070
Cancellation of FCAL common stock owned by PacWest (at acquisition date fair value)										0		0
First California Financial Group, Inc. [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition														31-May-13
Cash and due from banks														6,124	6,124
Interest-earning deposits in financial institutions														266,889	266,889
Investments securities available-for-sale														4,444	4,444
FHLB stock														9,518	9,518
Loans and leases														1,049,613	1,049,613
Equipment leased to others under operating leases														0	0
Premises and equipment														15,322	15,322
Foreclosed Assets														13,772	13,772
FDIC loss sharing asset														17,241	17,241
Income Tax Assets														33,360	33,360
Goodwill														129,070	129,070
Other intangible assets														7,927	7,927
Leases In Process														0	0
Other assets														27,576	27,576
Total assets acquired														1,580,856	1,580,856
Noninterest-bearing deposits														361,166	361,166
Interest-bearing deposits														739,713	739,713
Other borrowings														0	0
Borrowings from Parent														0	0
Subordinated Debentures														24,061	24,061
Discontinued operations														184,619	184,619
Accrued interest payable and other liabilities														19,729	19,729
Total liabilities assumed														1,329,288	1,329,288
Total consideration paid														251,568	251,568
Cash paid														0
PacWest common stock issued														242,268
Cancellation of FCAL common stock owned by PacWest (at acquisition date fair value)														9,300	9,300
Pacific Western Equipment Finance [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition																3-Jan-12
Cash and due from banks																7,092	7,092
Interest-earning deposits in financial institutions																0	0
Investments securities available-for-sale																0	0
FHLB stock																0	0
Loans and leases																140,959	140,959
Equipment leased to others under operating leases																0	0
Premises and equipment																0	0
Foreclosed Assets																0	0
FDIC loss sharing asset																0	0
Income Tax Assets																0	0
Goodwill																19,033	19,033
Other intangible assets																1,700	1,700
Leases In Process																19,162	19,162
Other assets																1,887	1,887
Total assets acquired																189,833	189,833
Noninterest-bearing deposits																0	0
Interest-bearing deposits																0	0
Other borrowings																15,839	15,839
Borrowings from Parent																128,677	128,677
Subordinated Debentures																0	0
Discontinued operations																0	0
Accrued interest payable and other liabilities																10,317	10,317
Total liabilities assumed																154,833	154,833
Total consideration paid																35,000	35,000
Cash paid																35,000
PacWest common stock issued																0
Cancellation of FCAL common stock owned by PacWest (at acquisition date fair value)																$0	$0
[1]	(1)The increase in the goodwill for the Community Banking segment and National Lending segment during 2014 was due primarily to $1.5 billion from the CapitalSource merger.
[2]	(1) The CapitalSouce, Inc. amount includes a $484 million receivable for securities sales proceeds.

Acquisition_Details_1

Acquisition (Details 1) (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
Business Combinations [Abstract]
Business Combination, Severance and Employee-related									$57,868	[1]	$21,497	[1]	$260	[1]
Business Combination, System Conversion and Integration									1,868		3,829		1,312
Business Combinations, Asset Writedowns Lease Terminations and other facilities-related									6,353		3,212		0
Business Combinations, Segment or Division reorganization									10,073		0		0
Business Combinations, Banking Fees									16,117		5,309		1,298
Business Combinations, Other Expenses									8,737		6,965		1,219
Acquisition, integration and reorganization costs	$83,021	$85,609	$83,167	$50,530	$49,984	$51,170	$46,233	$43,991	$101,016		$40,812		$4,089
[1]	(1)Amount includes $26.1 million in 2014 and $12.4 million in 2013 for accelerated vesting of restricted stock.

Acquisitions_Details_2

Acquisitions (Details 2) (Capitalsource, Inc. [Member], USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Capitalsource, Inc. [Member]
Business Acquisition [Line Items]
Pro Forma Revenue (net interest income plus noninterest income)	$797,296	$833,373
Pro forma net earnings from continuing operations	$252,258	$251,347
Pro forma net earnings from continuing operations per share - Basic	$2.45	$2.46
Pro forma net earnings from continuing operations per share - Diluted	$2.45	$2.46

Acquisitions_Details_Textuals

Acquisitions (Details Textuals) (USD $)	3 Months Ended										12 Months Ended					0 Months Ended		9 Months Ended		0 Months Ended	1 Months Ended	0 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	Apr. 07, 2014	Apr. 07, 2014	Dec. 31, 2014		31-May-13	31-May-13	Aug. 01, 2012	Aug. 01, 2012	Apr. 03, 2012	Apr. 03, 2012	Jan. 03, 2012	Jan. 03, 2012	Dec. 31, 2011
																bank_branch	bank_branch				bank_branch
Business Acquisition [Line Items]
Common Stock, Par or Stated Value Per Share	$0.01					$0.01					$0.01		$0.01					$0.01
Goodwill	$1,720,479,000	[1]				$208,743,000	[1]				$1,720,479,000	[1]	$208,743,000	[1]	$79,866,000			$1,720,479,000	[1]									$39,141,000
Goodwill, Impairment Loss											6,645,000
Impairment of Intangible Assets, Finite-lived											804,000		0		0
Acquisition, integration and reorganization costs	83,021,000		85,609,000	83,167,000	50,530,000	49,984,000		51,170,000	46,233,000	43,991,000	101,016,000		40,812,000		4,089,000
Capitalsource, Inc. [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition											7-Apr-14						7-Apr-14
Total consideration paid																3,077,188,000	3,077,188,000
Business Acquisition, Share Price																$2.47	$2.47
Business Acquisition Shares Receivable By Stockholders Of Acquiree Ratio																0.2837	0.2837
Common Stock, Par or Stated Value Per Share																$45.83	$45.83
Common Stock, Value, Outstanding																3,100,000,000	3,100,000,000
Business Integration Completion Date																12-Apr-14
Number of Branches																21	21
Number Of Operating Branches Closed As Part Of Integration And Consolidation Plan																12	12
Number Of Operating Branches Which Overlapped With Existing Branches																1	1
Goodwill																1,518,381,000	1,518,381,000
Pro forma revenues (net interest income plus noninterest income)																		400,600,000
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual																		184,600,000
First California Financial Group, Inc. [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition																				31-May-13
Total consideration paid																				251,568,000	251,568,000
Number of Branches																				15	15
Goodwill																				129,070,000	129,070,000
Number Of Locations Added To Branch Network As Result Of Integration And Consolidation Plan																				7	7
American Perspective Bank [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition																						1-Aug-12
Total consideration paid																						58,076,000	58,076,000
Goodwill																						15,047,000	15,047,000
Celtic Capital Corporation [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition																								3-Apr-12
Total consideration paid																								18,000,000	18,000,000
Goodwill																								6,645,000	6,645,000
Asset Based Lending Maximum																								5,000,000	5,000,000
Goodwill, Impairment Loss				-6,600,000
Pacific Western Equipment Finance [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition																										3-Jan-12
Total consideration paid																										35,000,000	35,000,000
Goodwill																										19,033,000	19,033,000
Shares Of Common Stock [Member] | Capitalsource, Inc. [Member]
Business Acquisition [Line Items]
Stock Issued During Period, Shares, New Issues																56,600,000
Vesting Based On Service [Member] | Restricted Stock [Member]
Business Acquisition [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award Accelerated Compensation Cost											26,100,000		12,400,000
CDI and CRI [Member]
Business Acquisition [Line Items]
Impairment of Intangible Assets, Finite-lived											1,300,000		0		0
CDI and CRI [Member] | Celtic Capital Corporation [Member]
Business Acquisition [Line Items]
Impairment of Intangible Assets, Finite-lived				$500,000
[1]	(1)The increase in the goodwill for the Community Banking segment and National Lending segment during 2014 was due primarily to $1.5 billion from the CapitalSource merger.

Goodwill_and_Other_Intangible_2

Goodwill and Other Intangible Assets (Details) (USD $)	12 Months Ended			3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2012	Jun. 30, 2014	Dec. 31, 2013	Apr. 03, 2012	Aug. 01, 2012	31-May-13
Goodwill [Roll Forward]
Goodwill	$208,743	[1]	$39,141
Goodwill, Acquired During Period	1,518,381		19,033
Goodwill, Impairment Loss	-6,645
Goodwill	1,720,479	[1]	79,866
Celtic Capital Corporation [Member]
Goodwill [Roll Forward]
Goodwill						6,645
Goodwill, Acquired During Period			6,645
Goodwill, Impairment Loss				6,600
Goodwill						6,645
American Perspective Bank [Member]
Goodwill [Roll Forward]
Goodwill							15,047
Goodwill, Other Changes					-193
Goodwill, Acquired During Period			15,047
Goodwill							15,047
First California Financial Group, Inc. [Member]
Goodwill [Roll Forward]
Goodwill								129,070
Goodwill, Acquired During Period					129,070
Goodwill								$129,070
[1]	(1)The increase in the goodwill for the Community Banking segment and National Lending segment during 2014 was due primarily to $1.5 billion from the CapitalSource merger.

Goodwill_and_Other_Intangible_3

Goodwill and Other Intangible Assets (Details 1) (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
Finite-lived Intangible Assets [Roll Forward]
Balance, beginning of year				$48,963				$45,412	$48,963	$45,412	$67,100
Balance, beginning of year				-31,715				-30,689	-31,715	-30,689	-49,685
Additions due to acquisitions									6,720	7,927	4,924
Additions	-7,381	-5,193	-86,242	-2,200	-16,673	-5,450	-17,997	-692	-6,268	-5,402	-6,326
Fully amortized portion									-1,293	-4,376	-20,746
Write-off due to the asset financing segment reorganization									-804	0	0
Removal due to branch sale									0	0	4,576
Balance, end of year	53,090				48,963				53,090	48,963	45,412
Net CDI and CRI, end of year	17,204				17,248				17,204	17,248	14,723
Net CDI and CRI, end of year	-35,886				-31,715				-35,886	-31,715	-30,689
CDI and CRI [Member]
Finite-lived Intangible Assets [Roll Forward]
Fully amortized portion									-1,293	-4,376	-20,746
Write-off due to the asset financing segment reorganization									-1,300	0	0
Removal due to branch sale									$0	$0	$5,866

Goodwill_and_Other_Intangible_4

Goodwill and Other Intangible Assets (Details Textual) (USD $)	12 Months Ended			3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2014
Goodwill, Impairment Loss	($6,645,000)
Impairment of Intangible Assets, Finite-lived	804,000	0	0
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	4 years 6 months 20 days
Aggregate Amortization Expense 2015	6,000,000
Aggregate Amortization Expense 2016	4,100,000
Aggregate Amortization Expense 2017	2,300,000
Aggregate Amortization Expense 2018	2,000,000
Aggregate Amortization Expense 2019	1,700,000
CDI and CRI [Member]
Impairment of Intangible Assets, Finite-lived	1,300,000	0	0
CDI and CRI [Member] | Celtic Capital Corporation [Member]
Impairment of Intangible Assets, Finite-lived				$500,000

Investments_Details_1

Investments (Details 1) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	$1,522,871	$1,500,516
Available-for-sale Securities, Gross Unrealized Gain	47,908	27,774
Available-for-sale Securities, Gross Unrealized Loss	-3,602	-33,545
Securities available‑for‑sale	1,567,177	1,494,745
Government agency and government-sponsored enterprise pass through securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	515,902	691,944
Available-for-sale Securities, Gross Unrealized Gain	20,142	18,012
Available-for-sale Securities, Gross Unrealized Loss	-372	-2,768
Government agency and government-sponsored enterprise collateralized mortgage obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	275,513	197,069
Available-for-sale Securities, Gross Unrealized Gain	3,513	388
Available-for-sale Securities, Gross Unrealized Loss	-1,080	-4,584
Covered private label collateralized mortgage obligation [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	26,889	30,502
Available-for-sale Securities, Gross Unrealized Gain	7,153	7,552
Available-for-sale Securities, Gross Unrealized Loss	-95	-150
Other Private Label Collateralized Mortgage Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	10,961	0
Available-for-sale Securities, Gross Unrealized Gain	46	0
Available-for-sale Securities, Gross Unrealized Loss	-93	0
Securities available‑for‑sale		0
Municipal securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	521,499	459,182
Available-for-sale Securities, Gross Unrealized Gain	15,899	1,749
Available-for-sale Securities, Gross Unrealized Loss	-1,282	-24,273
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	110,074	84,119
Available-for-sale Securities, Gross Unrealized Gain	597	71
Available-for-sale Securities, Gross Unrealized Loss	-562	-1,483
US Government-sponsored Enterprises Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	36,232	10,046
Available-for-sale Securities, Gross Unrealized Gain	525	0
Available-for-sale Securities, Gross Unrealized Loss	0	-174
Other securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	25,801	27,654
Available-for-sale Securities, Gross Unrealized Gain	33	2
Available-for-sale Securities, Gross Unrealized Loss	($118)	($113)

Investments_Details_2

Investments (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	$106,602	$773,925
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	-882	-33,356
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	173,724	5,032
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	-2,720	-189
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	280,326	778,957
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	-3,602	-33,545
Government agency and government-sponsored enterprise pass through securities
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	10,711	148,662
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	-13	-2,767
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	27,100	32
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	-359	-1
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	37,811	148,694
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	-372	-2,768
Government agency and government-sponsored enterprise collateralized mortgage obligations [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	23,908	179,938
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	-73	-4,486
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	40,652	4,383
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	-1,007	-98
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	64,560	184,321
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	-1,080	-4,584
Covered private label collateralized mortgage obligation [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	0	1,640
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	0	-60
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	1,000	617
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	-95	-90
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	1,000	2,257
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	-95	-150
Other Private Label Collateralized Mortgage Obligations [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	1,618
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	-93
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	1,618
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	-93
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	11,854	337,208
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	-66	-24,273
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	84,822
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	-1,216	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	96,676	337,208
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	-1,282	-24,273
Corporate Debt Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	52,071	72,636
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	-547	-1,483
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	10,131	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	-15	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	62,202	72,636
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	-562	-1,483
US Government-sponsored Enterprises Debt Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss		9,872
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		-174
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss		9,872
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		-174
Other securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	6,440	23,969
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	-90	-113
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	10,019	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	-28	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	16,459	23,969
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	($118)	($113)

Investments_Details_3

Investments (Details 3) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Investment Securities, Available-for-Sale, Amortized Cost
Due in one year or less	$4,567
Due after one year through five years	85,288
Due after five years through ten years	262,556
Due after ten years	1,170,460
Total	1,522,871	1,500,516
Investment Securities, Available-for-Sale, Estimated Fair Value
Due in one year or less	4,596
Due after one year through five years	85,219
Due after five years through ten years	268,665
Due after ten years	1,208,697
Available-for-sale, at fair value	$1,567,177	$1,494,745

Investments_Details_4

Investments (Details 4) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Investments, Debt and Equity Securities [Abstract]
Interest Income, Securities, Operating, Taxable	$30,135	$23,542	$29,652
Interest Income, Securities, Operating, Tax Exempt	13,597	11,777	5,559
Investment Income, Dividend	3,613	1,604	446
Investment Income, Interest and Dividend	$47,345	$36,923	$35,657

Investments_Details_Textual

Investments (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Apr. 07, 2014	31-May-13	Aug. 01, 2012
Schedule of Available-for-sale Securities [Line Items]
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	$0	$0	$1,115,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	0	0
Available For Sale Securities Pledged As Collateral Amortized Cost	308,600,000
Proceeds from sales	465,608,000	22,415,000	90,745,000
Payments to Acquire Investments	236,700,000	550,200,000	485,900,000
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Reclassification Adjustments, Net of Tax	32,601,000	-30,946,000	10,169,000
FDIC Loss Share Income Offset			892,000
Federal Home Loan Bank stock, at cost	40,609,000	27,939,000
Government agency and government-sponsored enterprise pass through securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales	460,800,000		43,900,000
Available-for-sale Securities, Gross Realized Gains	4,800,000		1,200,000
Collateralized Loan Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales		10,000,000
Available-for-sale Securities, Gross Realized Losses		272,000
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales		12,400,000
Available-for-sale Securities, Gross Realized Gains		409,000
Capitalsource, Inc. [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales	322,700,000
Available-for-sale Securities, Gross Realized Gains	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities				382,797,000
First California Financial Group, Inc. [Member]
Schedule of Available-for-sale Securities [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities					4,444,000
First California Financial Group, Inc. [Member] | Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Gain (Loss) on Sale of Investments	5,200,000
American Perspective Bank [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales			45,600,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities						48,887,000
Gain (Loss) on Sale of Investments			0
Business Acquisition Purchase Price Allocation, Investment Securities			48,900,000
Below threshold [Member] | Affinity Bank [Member]
Schedule of Available-for-sale Securities [Line Items]
FDIC Indemnification rate on covered assets	80.00%
Federal Home Loan Bank of San Francisco [Member]
Schedule of Available-for-sale Securities [Line Items]
Increase (Decrease) in Marketable Securities, Restricted	$12,700,000

Loans_and_Leases_Details

Loans and Leases (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross	$11,904,684	$4,313,335
Loans And Leases Net Of Discounts Covered	290,791	382,796
Loans and Leases Receivable, Deferred Income	-22,252	-983
Loans held for investment, net	11,882,432	4,312,352
Loans and Leases Receivable, Allowance	-84,455	-82,034
Loans and Leases Receivable Allowance Covered And Noncovered	84,455	82,034		91,968
Loans and leases, net	11,797,977	4,230,318
Loans and Leases Receivable, Net Reported Amount, Covered	276,792	361,003
Total loans and leases, net	11,797,977	4,230,318
Mortgage Loans on Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross	5,607,316	2,795,998
Loans And Leases Net Of Discounts Covered	256,489	371,134
Loans and Leases Receivable, Allowance	-25,097	-26,078
Real Estate Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross	316,086	219,517
Loans And Leases Net Of Discounts Covered	6,924	10,427
Loans and Leases Receivable, Allowance	-4,248	-4,298
Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross	5,879,575	1,242,750
Loans And Leases Net Of Discounts Covered	27,155	974
Loans and Leases Receivable, Allowance	-39,858	-26,921
Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross	101,707	55,070
Loans And Leases Net Of Discounts Covered	284	261
Loans held for investment, net	101,483
Loans and Leases Receivable, Allowance	-1,253	-2,944
NonCovered [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross	11,613,832	3,930,539
Loans and Leases Receivable, Deferred Income	-22,191	-983
Loans held for investment, net	11,591,641	3,929,556	[1]
Loans and Leases Receivable, Allowance	-70,456	-60,241		-65,899	-85,313
Loans and leases, net	11,521,185	3,869,315
NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross	5,350,827	2,424,864
Loans held for investment, net	5,340,560	2,422,107	[1]
Loans and Leases Receivable, Allowance		-26,078		-38,700
NonCovered [Member] | Real Estate Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross	309,162	209,090
Loans held for investment, net	307,135	207,779	[1]
Loans and Leases Receivable, Allowance		-4,298		-3,221
NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross	5,852,420	1,241,776
Loans held for investment, net	5,842,463	1,244,785	[1]
Loans and Leases Receivable, Allowance		-26,921		-22,252
NonCovered [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross	101,423	54,809
Loans held for investment, net		54,885	[1]
Loans and Leases Receivable, Allowance		-2,944		-1,726
Purchased Credit Impaired Loans and Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans And Leases Net Of Discounts Covered	290,852	382,796
Loans and Leases Receivable, Deferred Income	-61	0
Loans held for investment, net	290,791	382,796	[1]
Loans and Leases Receivable, Allowance, Covered	-13,999	-21,793		-26,069
Loans and Leases Receivable, Net Reported Amount, Covered	$276,792	$361,003
[1]	(1)As of December 31, 2013, the amounts of loans covered by loss sharing provisions of FDIC loss sharing agreements in the Non-PCI and PCI categories were $85.9 million and $362.5 million.

Loans_and_Leases_Loans_and_Lea

Loans and Leases Loans and Leases (Details 1) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Allowance	$84,455	$82,034
Valuation Allowances and Reserves, Balance	76,767	67,816	72,119	93,783
Allowance for Loan and Lease Losses, Write-offs	-21,452	-11,225
Valuation Allowances and Reserves, Deductions	-11,875	-11,159	-13,070
Allowance for Loan and Lease Loss, Recovery of Bad Debts	11,110	6,856
Valuation Allowances and Reserves, Recoveries	10,344	6,856	3,406
Provision for Loan and Lease Losses	12,763	-5,565
Valuation Allowances and Reserves, Charged to Cost and Expense	10,482	0	-12,000
NonCovered [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Allowance	70,456	60,241	65,899	85,313
Allowance for Loan and Lease Losses, Write-offs	-11,875	-11,159	-13,070
Allowance for Loan and Lease Loss, Recovery of Bad Debts	10,344	6,856	3,406
Provision for Loan and Lease Losses	11,746	-1,355	-9,750
Commitments to Extend Credit [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Valuation Allowances and Reserves, Balance	6,311	7,575	6,220	8,470
Valuation Allowances and Reserves, Deductions	0	0	0
Valuation Allowances and Reserves, Recoveries	0	0	0
Valuation Allowances and Reserves, Charged to Cost and Expense	($1,264)	$1,355	($2,250)

Loans_and_Leases_Details_2

Loans and Leases (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Allowance	$84,455	$82,034
Loans and Leases Receivable Allowance Covered And Noncovered	84,455	82,034		91,968
Allowance for Loan and Lease Losses, Write-offs	-21,452	-11,225
Allowance for Loan and Lease Loss, Recovery of Bad Debts	11,110	6,856
Provision for Loan and Lease Losses	12,763	-5,565
Loans held for investment, net	11,882,432	4,312,352
Loans and Leases Receivable Net Of Deferred Income Covered And Noncovered	11,882,432	4,312,352	[1]
Mortgage Loans on Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Allowance	25,097	26,078
Real Estate Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Allowance	4,248	4,298
Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Allowance	39,858	26,921
Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Allowance	1,253	2,944
Loans held for investment, net	101,483
Purchased Credit Impaired Loans and Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Allowance, Covered	13,999	21,793		26,069
Allowance for Loan and Lease Losses, Write-offs	-9,577	-66
Allowance for Loan and Lease Loss, Recovery of Bad Debts	766	0
Provision for Loan and Lease Losses	1,017	-4,210
Financing Receivable, Allowance for Credit Losses, Acquired with Deteriorated Credit Quality	13,999	21,793
Loans held for investment, net	290,791	382,796	[1]
Financing Receivable, Acquired with Deteriorated Credit Quality	290,791	382,796
Purchased Credit Impaired Loans and Leases [Member] | Covered [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, net	100,400	362,500
Non Purchased Credit Impaired Loans and Leases [Member] | Covered [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, net	61,500	85,900
NonCovered [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Allowance	70,456	60,241		65,899	85,313
Allowance for Loan and Lease Losses, Write-offs	-11,875	-11,159		-13,070
Allowance for Loan and Lease Loss, Recovery of Bad Debts	10,344	6,856		3,406
Provision for Loan and Lease Losses	11,746	-1,355		-9,750
Financing Receivable, Individually Evaluated for Impairment	10,774	7,600
Financing Receivable, Collectively Evaluated for Impairment	59,682	52,641
Loans held for investment, net	11,591,641	3,929,556	[1]
Financing Receivable, Individually Evaluated for Impairment	118,865	88,422
Financing Receivable, Collectively Evaluated for Impairment	11,472,776	3,841,134
NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Allowance		26,078		38,700
Allowance for Loan and Lease Losses, Write-offs	-2,080	-4,552
Allowance for Loan and Lease Loss, Recovery of Bad Debts	2,640	2,507
Provision for Loan and Lease Losses	-1,541	-10,577
Financing Receivable, Individually Evaluated for Impairment	693	2,188
Financing Receivable, Collectively Evaluated for Impairment	24,404	23,890
Loans held for investment, net	5,340,560	2,422,107	[1]
Financing Receivable, Individually Evaluated for Impairment	57,857	62,276
Financing Receivable, Collectively Evaluated for Impairment	5,282,703	2,359,831
NonCovered [Member] | Real Estate Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Allowance		4,298		3,221
Allowance for Loan and Lease Losses, Write-offs	0	0
Allowance for Loan and Lease Loss, Recovery of Bad Debts	156	1,654
Provision for Loan and Lease Losses	-206	-577
Financing Receivable, Individually Evaluated for Impairment	69	169
Financing Receivable, Collectively Evaluated for Impairment	4,179	4,129
Loans held for investment, net	307,135	207,779	[1]
Financing Receivable, Individually Evaluated for Impairment	10,555	7,512
Financing Receivable, Collectively Evaluated for Impairment	296,580	200,267
NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Allowance		26,921		22,252
Allowance for Loan and Lease Losses, Write-offs	-9,463	-6,409
Allowance for Loan and Lease Loss, Recovery of Bad Debts	6,265	2,621
Provision for Loan and Lease Losses	16,135	8,457
Financing Receivable, Individually Evaluated for Impairment	9,975	5,003
Financing Receivable, Collectively Evaluated for Impairment	29,883	21,918
Loans held for investment, net	5,842,463	1,244,785	[1]
Financing Receivable, Individually Evaluated for Impairment	46,709	17,932
Financing Receivable, Collectively Evaluated for Impairment	5,795,754	1,226,853
NonCovered [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Allowance		2,944		1,726
Allowance for Loan and Lease Losses, Write-offs	-332	-198
Allowance for Loan and Lease Loss, Recovery of Bad Debts	1,283	74
Provision for Loan and Lease Losses	-2,642	1,342
Financing Receivable, Individually Evaluated for Impairment	37	240
Financing Receivable, Collectively Evaluated for Impairment	1,216	2,704
Loans held for investment, net		54,885	[1]
Financing Receivable, Individually Evaluated for Impairment	3,744	702
Financing Receivable, Collectively Evaluated for Impairment	$97,739	$54,183
[1]	(1)As of December 31, 2013, the amounts of loans covered by loss sharing provisions of FDIC loss sharing agreements in the Non-PCI and PCI categories were $85.9 million and $362.5 million.

Loans_and_Leases_Details_3

Loans and Leases (Details 3) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	$11,882,432	$4,312,352
Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	101,483
NonCovered [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired Financing Receivable, Related Allowance	10,774	7,600
Financing Receivable, Individually Evaluated for Impairment	10,774	7,600
Loans held for investment, net	11,591,641	3,929,556	[1]
NonCovered [Member] | Hospitality [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired Financing Receivable, Related Allowance	47	198
NonCovered [Member] | SBA Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired Financing Receivable, Related Allowance	0	230
NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired Financing Receivable, Related Allowance		2,188
Financing Receivable, Individually Evaluated for Impairment	693	2,188
Loans held for investment, net	5,340,560	2,422,107	[1]
NonCovered [Member] | Residential Real Estate Construction Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired Financing Receivable, Related Allowance	46	168
NonCovered [Member] | Real Estate Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired Financing Receivable, Related Allowance		169
Financing Receivable, Individually Evaluated for Impairment	69	169
Loans held for investment, net	307,135	207,779	[1]
NonCovered [Member] | Collateralized Loan Obligations [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired Financing Receivable, Related Allowance	3,771	4,270
NonCovered [Member] | Unsecured Commercial Member [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired Financing Receivable, Related Allowance	799	375
NonCovered [Member] | Asset Based [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired Financing Receivable, Related Allowance	137	180
NonCovered [Member] | Cash Flow [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired Financing Receivable, Related Allowance	2,667	0
NonCovered [Member] | Equipment Finance Commercial Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired Financing Receivable, Related Allowance	2,601	0
NonCovered [Member] | SBA Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired Financing Receivable, Related Allowance	0	178
NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired Financing Receivable, Related Allowance		5,003
Financing Receivable, Individually Evaluated for Impairment	9,975	5,003
Loans held for investment, net	5,842,463	1,244,785	[1]
NonCovered [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired Financing Receivable, Related Allowance	37	240
Financing Receivable, Individually Evaluated for Impairment	37	240
Loans held for investment, net		54,885	[1]
NonCovered [Member] | Nonclassified [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	11,349,030	3,802,245
NonCovered [Member] | Nonclassified [Member] | Hospitality [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	542,458	168,216
NonCovered [Member] | Nonclassified [Member] | SBA Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	364,786	39,869
NonCovered [Member] | Nonclassified [Member] | Real Estate Other Class [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	4,336,330	2,132,109
NonCovered [Member] | Nonclassified [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	5,243,574	2,340,194
NonCovered [Member] | Nonclassified [Member] | Residential Real Estate Construction Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	96,326	58,131
NonCovered [Member] | Nonclassified [Member] | Commercial Real Estate Construction Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	207,061	142,607
NonCovered [Member] | Nonclassified [Member] | Real Estate Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	303,387	200,738
NonCovered [Member] | Nonclassified [Member] | Collateralized Loan Obligations [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	416,754	567,643
NonCovered [Member] | Nonclassified [Member] | Unsecured Commercial Member [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	130,501	151,896
NonCovered [Member] | Nonclassified [Member] | Asset Based [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	1,783,304	195,569
NonCovered [Member] | Nonclassified [Member] | Cash Flow [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	2,376,530	0
NonCovered [Member] | Nonclassified [Member] | Equipment Finance Commercial Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	953,516	272,851
NonCovered [Member] | Nonclassified [Member] | SBA Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	44,054	22,880
NonCovered [Member] | Nonclassified [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	5,704,659	1,210,839
NonCovered [Member] | Nonclassified [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	97,410	50,474
NonCovered [Member] | Classified [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	242,611	127,311
NonCovered [Member] | Classified [Member] | Hospitality [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	17,761	12,337
NonCovered [Member] | Classified [Member] | SBA Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	11,141	5,297
NonCovered [Member] | Classified [Member] | Real Estate Other Class [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	68,084	64,279
NonCovered [Member] | Classified [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	96,986	81,913
NonCovered [Member] | Classified [Member] | Residential Real Estate Construction Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	402	750
NonCovered [Member] | Classified [Member] | Commercial Real Estate Construction Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	3,346	6,291
NonCovered [Member] | Classified [Member] | Real Estate Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	3,748	7,041
NonCovered [Member] | Classified [Member] | Collateralized Loan Obligations [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	22,433	18,838
NonCovered [Member] | Classified [Member] | Unsecured Commercial Member [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	1,323	1,856
NonCovered [Member] | Classified [Member] | Asset Based [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	11,547	6,859
NonCovered [Member] | Classified [Member] | Cash Flow [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	83,321	0
NonCovered [Member] | Classified [Member] | Equipment Finance Commercial Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	15,973	632
NonCovered [Member] | Classified [Member] | SBA Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	3,207	5,761
NonCovered [Member] | Classified [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	137,804	33,946
NonCovered [Member] | Classified [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	4,073	4,411
Purchased Credit Impaired Loans and Leases [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	290,791	382,796	[1]
Purchased Credit Impaired Loans and Leases [Member] | Covered [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	100,400	362,500
Unsecured Commercial Member [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	131,824	153,752
Asset Based [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	1,794,851	202,428
Cash Flow [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	2,459,851	0
Equipment Finance Commercial Financing Receivable [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	969,489	273,483
SBA Financing Receivable [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	47,261	28,641
Residential Real Estate Construction Financing Receivable [Member] | NonCovered [Member] | Real Estate Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	96,728	58,881
Commercial Real Estate Construction Financing Receivable [Member] | NonCovered [Member] | Real Estate Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	210,407	148,898
Hospitality [Member] | NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	560,219	180,553
SBA Loans [Member] | NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	375,927	45,166
Real Estate Other Class [Member] | NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, net	$4,404,414	$2,196,388
[1]	(1)As of December 31, 2013, the amounts of loans covered by loss sharing provisions of FDIC loss sharing agreements in the Non-PCI and PCI categories were $85.9 million and $362.5 million.

Loans_and_Leases_Details_4

Loans and Leases (Details 4) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Delinquent loans in loan portfolio
30-89 Days Past Due	$8,700	$4,200
Loans held for investment, net	11,882,432	4,312,352
Consumer Portfolio Segment [Member]
Delinquent loans in loan portfolio
Loans held for investment, net	101,483
NonCovered [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	19,406	23,897
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	18,818	5,233
Financing Receivable, Recorded Investment, Past Due	38,224	29,130
Current	11,553,417	3,900,426
Loans held for investment, net	11,591,641	3,929,556	[1]
NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	11,628	15,590
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	11,987	2,406
Financing Receivable, Recorded Investment, Past Due	23,615	17,996
Current	5,316,945	2,404,111
Loans held for investment, net	5,340,560	2,422,107	[1]
NonCovered [Member] | Real Estate Construction [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	0	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	715	2,013
Financing Receivable, Recorded Investment, Past Due	715	2,013
Current	306,420	205,766
Loans held for investment, net	307,135	207,779	[1]
NonCovered [Member] | Commercial Portfolio Segment [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	7,677	4,988
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	2,970	814
Financing Receivable, Recorded Investment, Past Due	10,647	5,802
Current	5,831,816	1,238,983
Loans held for investment, net	5,842,463	1,244,785	[1]
NonCovered [Member] | Consumer Portfolio Segment [Member]
Delinquent loans in loan portfolio
Loans held for investment, net		54,885	[1]
Consumer Financing Receivable [Member] | NonCovered [Member] | Consumer Portfolio Segment [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	101	3,319
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	3,146	0
Financing Receivable, Recorded Investment, Past Due	3,247	3,319
Current	98,236	51,566
Loans held for investment, net		54,885
Collateralized Loan Obligations [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	878	473
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	965	259
Financing Receivable, Recorded Investment, Past Due	1,843	732
Current	437,344	585,749
Loans held for investment, net	439,187	586,481
Unsecured Commercial Member [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	69	83
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	45	68
Financing Receivable, Recorded Investment, Past Due	114	151
Current	131,710	153,601
Loans held for investment, net	131,824	153,752
Asset Based [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	0	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	0
Financing Receivable, Recorded Investment, Past Due	0	0
Current	1,794,851	202,428
Loans held for investment, net	1,794,851	202,428
Cash Flow [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	232
Financing Receivable, Recorded Investment, Past Due	232
Current	2,459,619
Loans held for investment, net	2,459,851	0
Equipment Finance Commercial Financing Receivable [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	6,525	2,662
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	366	244
Financing Receivable, Recorded Investment, Past Due	6,891	2,906
Current	962,598	270,577
Loans held for investment, net	969,489	273,483
SBA Financing Receivable [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	205	1,770
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	1,362	243
Financing Receivable, Recorded Investment, Past Due	1,567	2,013
Current	45,694	26,628
Loans held for investment, net	47,261	28,641
Residential Real Estate Construction Financing Receivable [Member] | NonCovered [Member] | Real Estate Construction [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	0	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	0
Financing Receivable, Recorded Investment, Past Due	0	0
Current	96,728	58,881
Loans held for investment, net	96,728	58,881
Commercial Real Estate Construction Financing Receivable [Member] | NonCovered [Member] | Real Estate Construction [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	0	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	715	2,013
Financing Receivable, Recorded Investment, Past Due	715	2,013
Current	209,692	146,885
Loans held for investment, net	210,407	148,898
Hospitality [Member] | NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	0	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	0
Financing Receivable, Recorded Investment, Past Due	0	0
Current	560,219	180,553
Loans held for investment, net	560,219	180,553
SBA Loans [Member] | NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	5,530	2,564
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	4,357	0
Financing Receivable, Recorded Investment, Past Due	9,887	2,564
Current	366,040	42,602
Loans held for investment, net	375,927	45,166
Real Estate Other Class [Member] | NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Delinquent loans in loan portfolio
30-89 Days Past Due	6,098	13,026
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	7,630	2,406
Financing Receivable, Recorded Investment, Past Due	13,728	15,432
Current	4,390,686	2,180,956
Loans held for investment, net	$4,404,414	$2,196,388
[1]	(1)As of December 31, 2013, the amounts of loans covered by loss sharing provisions of FDIC loss sharing agreements in the Non-PCI and PCI categories were $85.9 million and $362.5 million.

Loans_and_Leases_Details_5

Loans and Leases (Details 5) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	$11,882,432	$4,312,352
Non-PCI nonaccrual loans	83,621	46,774
Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	101,483
NonCovered [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	11,591,641	3,929,556	[1]
Non-PCI nonaccrual loans		3,929,556
NonCovered [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net		54,885	[1]
NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	5,340,560	2,422,107	[1]
NonCovered [Member] | Real Estate Construction [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	307,135	207,779	[1]
NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	5,842,463	1,244,785	[1]
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Hospitality [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	6,366	6,723
Nonperforming Financing Receivable [Member] | NonCovered [Member] | SBA Loans [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	11,141	2,602
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Real Estate Other Class [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	20,105	18,648
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Residential Real Estate Construction Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	381	389
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Commercial Real Estate Construction Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	1,178	2,830
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Collateralized Loan Obligations [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	5,450	9,991
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Unsecured Commercial Member [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	639	458
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Asset Based [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	4,574	1,070
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Cash Flow [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	15,964	0
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Equipment Finance Commercial Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	11,131	632
Nonperforming Financing Receivable [Member] | NonCovered [Member] | SBA Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	3,207	3,037
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	3,485	394
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	37,612	27,973
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Real Estate Construction [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	1,559	3,219
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	40,965	15,188
Performing Financing Receivable [Member] | NonCovered [Member]
Financing Receivable, Impaired [Line Items]
Non-PCI nonaccrual loans	11,508,020	3,882,782
Performing Financing Receivable [Member] | NonCovered [Member] | Hospitality [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	553,853	173,830
Performing Financing Receivable [Member] | NonCovered [Member] | SBA Loans [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	364,786	42,564
Performing Financing Receivable [Member] | NonCovered [Member] | Real Estate Other Class [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	4,384,309	2,177,740
Performing Financing Receivable [Member] | NonCovered [Member] | Residential Real Estate Construction Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	96,347	58,492
Performing Financing Receivable [Member] | NonCovered [Member] | Commercial Real Estate Construction Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	209,229	146,068
Performing Financing Receivable [Member] | NonCovered [Member] | Collateralized Loan Obligations [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	433,737	576,490
Performing Financing Receivable [Member] | NonCovered [Member] | Unsecured Commercial Member [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	131,185	153,294
Performing Financing Receivable [Member] | NonCovered [Member] | Asset Based [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	1,790,277	201,358
Performing Financing Receivable [Member] | NonCovered [Member] | Cash Flow [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	2,443,887	0
Performing Financing Receivable [Member] | NonCovered [Member] | Equipment Finance Commercial Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	958,358	272,851
Performing Financing Receivable [Member] | NonCovered [Member] | SBA Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	44,054	25,604
Performing Financing Receivable [Member] | NonCovered [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	97,998	54,491
Performing Financing Receivable [Member] | NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	5,302,948	2,394,134
Performing Financing Receivable [Member] | NonCovered [Member] | Real Estate Construction [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	305,576	204,560
Performing Financing Receivable [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	5,801,498	1,229,597
Collateralized Loan Obligations [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	439,187	586,481
Unsecured Commercial Member [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	131,824	153,752
Asset Based [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	1,794,851	202,428
Cash Flow [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	2,459,851	0
Equipment Finance Commercial Financing Receivable [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	969,489	273,483
SBA Financing Receivable [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	47,261	28,641
Residential Real Estate Construction Financing Receivable [Member] | NonCovered [Member] | Real Estate Construction [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	96,728	58,881
Commercial Real Estate Construction Financing Receivable [Member] | NonCovered [Member] | Real Estate Construction [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	210,407	148,898
Hospitality [Member] | NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	560,219	180,553
SBA Loans [Member] | NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	375,927	45,166
Real Estate Other Class [Member] | NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	$4,404,414	$2,196,388
[1]	(1)As of December 31, 2013, the amounts of loans covered by loss sharing provisions of FDIC loss sharing agreements in the Non-PCI and PCI categories were $85.9 million and $362.5 million.

Loans_and_Leases_Details_6

Loans and Leases (Details 6) (USD $)	3 Months Ended				12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013		Dec. 31, 2012		Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Gross							$11,904,684	$4,313,335
Loans held for investment, net							11,882,432	4,312,352
Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Gross							101,707	55,070
Loans held for investment, net							101,483
Mortgage Loans on Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Gross							5,607,316	2,795,998
Real Estate Construction [Member]
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Gross							316,086	219,517
Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Gross							5,879,575	1,242,750
NonCovered [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance							10,774	7,600
Impaired Financing Receivable Performing Restructured Loans							35,244	41,648
Impaired Financing Receivable, Recorded Investment							118,865	88,422
Financing Receivable, Recorded Investment, Nonaccrual Status							83,621
Impaired Financing Receivable, Unpaid Principal Balance							150,620	113,813
Financing Receivable, Individually Evaluated for Impairment							10,774	7,600
Loans and Leases Receivable, Gross							11,613,832	3,930,539
Impaired Financing Receivable, Average Recorded Investment	86,781	[1]	73,711	[1]	129,832	[1]
Impaired Financing Receivable, Interest Income, Accrual Method	1,471		1,976		4,724
Financing Receivable, Individually Evaluated for Impairment							118,865	88,422
Loans held for investment, net							11,591,641	3,929,556	[2]
NonCovered [Member] | Hospitality [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment							1,946	5,717
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance							1,945	6,215
Impaired Financing Receivable, Related Allowance							47	198
Impaired Financing Receivable, with No Related Allowance, Recorded Investment							6,366	3,013
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance							7,593	3,385
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	1,946	[1]	5,717	[1]	8,954	[1]
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	67		81		80
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	6,366	[1]	3,013	[1]	0	[1]
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0		0		0
NonCovered [Member] | SBA Loans [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment							0	1,642
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance							0	1,643
Impaired Financing Receivable, Related Allowance							0	230
Impaired Financing Receivable, with No Related Allowance, Recorded Investment							11,141	2,602
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance							14,708	3,646
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	0	[1]	1,642	[1]	827	[1]
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	0		90		41
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	6,610	[1]	2,601	[1]	1,472	[1]
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	77		0		0
NonCovered [Member] | Real Estate Mortgage Other Receivable [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment							9,136	15,937
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance							9,233	16,571
Impaired Financing Receivable, Related Allowance							646	1,760
Impaired Financing Receivable, with No Related Allowance, Recorded Investment							29,268	33,365
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance							40,643	46,062
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	9,136	[1]	13,205	[1]	51,441	[1]
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	409		509		2,070
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	21,652	[1]	27,912	[1]	29,316	[1]
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	315		1,060		1,523
NonCovered [Member] | Residential Real Estate Construction Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment							763	778
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance							763	778
Impaired Financing Receivable, Related Allowance							46	168
Impaired Financing Receivable, with No Related Allowance, Recorded Investment							21	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance							19	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	763	[1]	778	[1]	1,303	[1]
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	15		14		11
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	4	[1]	0	[1]	0	[1]
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0		0		0
NonCovered [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment							1,128	1,250
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance							4,934	1,250
Impaired Financing Receivable, Related Allowance							23	1
Impaired Financing Receivable, with No Related Allowance, Recorded Investment							8,643	5,484
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance							8,749	9,923
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	1,027	[1]	1,250	[1]	6,723	[1]
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	17		63		231
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	8,642	[1]	4,866	[1]	17,424	[1]
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	244		11		589
NonCovered [Member] | Collateralized Loan Obligations [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment							4,630	4,377
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance							5,246	4,692
Impaired Financing Receivable, Related Allowance							3,771	4,270
Impaired Financing Receivable, with No Related Allowance, Recorded Investment							5,566	6,700
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance							6,877	9,924
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	4,077	[1]	3,281	[1]	2,219	[1]
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	27		29		48
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	2,869	[1]	3,410	[1]	1,657	[1]
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	170		20		27
NonCovered [Member] | Unsecured Commercial Member [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment							912	801
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance							924	829
Impaired Financing Receivable, Related Allowance							799	375
Impaired Financing Receivable, with No Related Allowance, Recorded Investment							725	179
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance							809	247
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	661	[1]	772	[1]	2,273	[1]
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	21		33		20
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	126	[1]	157	[1]	148	[1]
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	1		0		0
NonCovered [Member] | Asset Based [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment							137	1,070
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance							247	1,070
Impaired Financing Receivable, Related Allowance							137	180
Impaired Financing Receivable, with No Related Allowance, Recorded Investment							4,436	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance							5,415	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	137	[1]	569	[1]	0	[1]
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	0		0		0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	3,270	[1]	0	[1]	132	[1]
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0		0		0
NonCovered [Member] | Cash Flow [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment							15,578	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance							17,970	0
Impaired Financing Receivable, Related Allowance							2,667	0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment							387	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance							919	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	7,837	[1]	0	[1]	0	[1]
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	0		0		0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	1	[1]	0	[1]	0	[1]
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0		0		0
NonCovered [Member] | Equipment Finance Commercial Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment							6,956	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance							7,268	0
Impaired Financing Receivable, Related Allowance							2,601	0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment							4,175	632
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance							7,528	632
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	3,802	[1]	0	[1]	0	[1]
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	0		0		0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	2,534	[1]	245	[1]	224	[1]
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0		0		0
NonCovered [Member] | SBA Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment							0	1,136
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance							0	1,136
Impaired Financing Receivable, Related Allowance							0	178
Impaired Financing Receivable, with No Related Allowance, Recorded Investment							3,207	3,037
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance							4,920	4,945
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	0	[1]	1,136	[1]	2,593	[1]
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	0		56		53
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	2,162	[1]	2,571	[1]	2,601	[1]
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	98		0		24
NonCovered [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment							143	424
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance							142	471
Impaired Financing Receivable, Related Allowance							37	240
Impaired Financing Receivable, with No Related Allowance, Recorded Investment							3,601	278
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance							3,768	394
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	132	[1]	425	[1]	389	[1]
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	8		10		7
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	3,027	[1]	161	[1]	136	[1]
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	2		0		0
Impaired Financing Receivable Performing Restructured Loans							259	308
Impaired Financing Receivable, Recorded Investment							3,744	702
Financing Receivable, Recorded Investment, Nonaccrual Status								394
Impaired Financing Receivable, Unpaid Principal Balance							3,910	865
Financing Receivable, Individually Evaluated for Impairment							37	240
Loans and Leases Receivable, Gross							101,423	54,809
Impaired Financing Receivable, Average Recorded Investment	3,159	[1]	586	[1]	525	[1]
Impaired Financing Receivable, Interest Income, Accrual Method	10		10		7
Financing Receivable, Individually Evaluated for Impairment							3,744	702
Loans held for investment, net								54,885	[2]
NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance								2,188
Impaired Financing Receivable Performing Restructured Loans							20,245	34,303
Impaired Financing Receivable, Recorded Investment							57,857	62,276
Financing Receivable, Recorded Investment, Nonaccrual Status								27,973
Impaired Financing Receivable, Unpaid Principal Balance							74,122	77,522
Financing Receivable, Individually Evaluated for Impairment							693	2,188
Loans and Leases Receivable, Gross							5,350,827	2,424,864
Impaired Financing Receivable, Average Recorded Investment	45,710	[1]	54,090	[1]	92,010	[1]
Impaired Financing Receivable, Interest Income, Accrual Method	868		1,740		3,714
Financing Receivable, Individually Evaluated for Impairment							57,857	62,276
Loans held for investment, net							5,340,560	2,422,107	[2]
NonCovered [Member] | Real Estate Construction [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance								169
Impaired Financing Receivable Performing Restructured Loans							8,996	4,293
Impaired Financing Receivable, Recorded Investment							10,555	7,512
Financing Receivable, Recorded Investment, Nonaccrual Status								3,219
Impaired Financing Receivable, Unpaid Principal Balance							14,465	11,951
Financing Receivable, Individually Evaluated for Impairment							69	169
Loans and Leases Receivable, Gross							309,162	209,090
Impaired Financing Receivable, Average Recorded Investment	10,436	[1]	6,894	[1]	25,450	[1]
Impaired Financing Receivable, Interest Income, Accrual Method	276		88		831
Financing Receivable, Individually Evaluated for Impairment							10,555	7,512
Loans held for investment, net							307,135	207,779	[2]
NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Related Allowance								5,003
Impaired Financing Receivable Performing Restructured Loans							5,744	2,744
Impaired Financing Receivable, Recorded Investment							46,709	17,932
Financing Receivable, Recorded Investment, Nonaccrual Status								15,188
Impaired Financing Receivable, Unpaid Principal Balance							58,123	23,475
Financing Receivable, Individually Evaluated for Impairment							9,975	5,003
Loans and Leases Receivable, Gross							5,852,420	1,241,776
Impaired Financing Receivable, Average Recorded Investment	27,476	[1]	12,141	[1]	11,847	[1]
Impaired Financing Receivable, Interest Income, Accrual Method	317		138		172
Financing Receivable, Individually Evaluated for Impairment							46,709	17,932
Loans held for investment, net							5,842,463	1,244,785	[2]
Nonperforming Financing Receivable [Member] | NonCovered [Member]
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Gross								46,774
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Hospitality [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net							6,366	6,723
Nonperforming Financing Receivable [Member] | NonCovered [Member] | SBA Loans [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net							11,141	2,602
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Residential Real Estate Construction Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net							381	389
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Collateralized Loan Obligations [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net							5,450	9,991
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Unsecured Commercial Member [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net							639	458
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Asset Based [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net							4,574	1,070
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Cash Flow [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net							15,964	0
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Equipment Finance Commercial Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net							11,131	632
Nonperforming Financing Receivable [Member] | NonCovered [Member] | SBA Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net							3,207	3,037
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net							3,485	394
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net							37,612	27,973
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Real Estate Construction [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net							1,559	3,219
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net							$40,965	$15,188
[1]	(1)For the loans and leases (excluding PCI loans) reported as impaired at December 31, 2014, 2013 and 2012, amounts were calculated based on the period of time such loans and leases were impaired during the reported period.
[2]	(1)As of December 31, 2013, the amounts of loans covered by loss sharing provisions of FDIC loss sharing agreements in the Non-PCI and PCI categories were $85.9 million and $362.5 million.

Loans_and_Leases_Details_7

Loans and Leases (Details 7) (USD $)	3 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
NonCovered [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	$129	$1,600			$921
Financing Receivable, Modifications, Number of Contracts			72	38	30
Financing Receivable, Modifications, Pre-Modification Recorded Investment			41,030	25,046	26,851
Financing Receivable, Modifications, Post-Modification Recorded Investment			34,457	25,046	25,830
NonCovered [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts			7	2	1
Financing Receivable, Modifications, Pre-Modification Recorded Investment			467	125	206
Financing Receivable, Modifications, Post-Modification Recorded Investment			467	125	206
Financing Receivable Troubled Debt Restructurings That Subsequently Defaulted [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts			3	6	3
Financing Receivable, Modifications, Subsequent Default, Recorded Investment			1,589	3,399	1,331
Financing Receivable Troubled Debt Restructurings That Subsequently Defaulted [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts			0	0	0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment			0	0	0
Collateralized Loan Obligations [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts			22	11	7
Financing Receivable, Modifications, Pre-Modification Recorded Investment			12,368	5,618	1,652
Financing Receivable, Modifications, Post-Modification Recorded Investment			6,336	5,618	1,652
Collateralized Loan Obligations [Member] | Financing Receivable Troubled Debt Restructurings That Subsequently Defaulted [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts			1	1	2
Financing Receivable, Modifications, Subsequent Default, Recorded Investment			390	419	458
Unsecured Commercial Member [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts			10	5	5
Financing Receivable, Modifications, Pre-Modification Recorded Investment			752	521	317
Financing Receivable, Modifications, Post-Modification Recorded Investment			752	521	317
Unsecured Commercial Member [Member] | NonCovered [Member] | Equipment Finance Commercial Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts			1
Financing Receivable, Modifications, Pre-Modification Recorded Investment			518
Financing Receivable, Modifications, Post-Modification Recorded Investment			518
Unsecured Commercial Member [Member] | Financing Receivable Troubled Debt Restructurings That Subsequently Defaulted [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts			0	2	0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment			0	66	0
Unsecured Commercial Member [Member] | Financing Receivable Troubled Debt Restructurings That Subsequently Defaulted [Member] | Equipment Finance Commercial Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts			0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment			0
Asset Based [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts				1
Financing Receivable, Modifications, Pre-Modification Recorded Investment				2,032
Financing Receivable, Modifications, Post-Modification Recorded Investment				2,032
Asset Based [Member] | Financing Receivable Troubled Debt Restructurings That Subsequently Defaulted [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts				1
Financing Receivable, Modifications, Subsequent Default, Recorded Investment				1,070
SBA Financing Receivable [Member] | NonCovered [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts			3	4	4
Financing Receivable, Modifications, Pre-Modification Recorded Investment			1,965	137	1,216
Financing Receivable, Modifications, Post-Modification Recorded Investment			1,965	137	1,216
SBA Financing Receivable [Member] | Financing Receivable Troubled Debt Restructurings That Subsequently Defaulted [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts			1	0	1
Financing Receivable, Modifications, Subsequent Default, Recorded Investment			1,144	0	873
Commercial Real Estate Construction Financing Receivable [Member] | NonCovered [Member] | Real Estate Construction [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts			4
Financing Receivable, Modifications, Pre-Modification Recorded Investment			5,507
Financing Receivable, Modifications, Post-Modification Recorded Investment			4,965
Commercial Real Estate Construction Financing Receivable [Member] | Financing Receivable Troubled Debt Restructurings That Subsequently Defaulted [Member] | Real Estate Construction [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts			0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment			0
Residential Real Estate Construction Financing Receivable [Member] | NonCovered [Member] | Real Estate Construction [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts				1
Financing Receivable, Modifications, Pre-Modification Recorded Investment				390
Financing Receivable, Modifications, Post-Modification Recorded Investment				390
Residential Real Estate Construction Financing Receivable [Member] | Financing Receivable Troubled Debt Restructurings That Subsequently Defaulted [Member] | Real Estate Construction [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts				0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment				0
Real Estate Construction [Member] | NonCovered [Member] | Real Estate Construction [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts					3
Financing Receivable, Modifications, Pre-Modification Recorded Investment					6,919
Financing Receivable, Modifications, Post-Modification Recorded Investment					6,919
Real Estate Construction [Member] | Financing Receivable Troubled Debt Restructurings That Subsequently Defaulted [Member] | Real Estate Construction [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts					0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment					0
Hospitality [Member] | NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts			1
Financing Receivable, Modifications, Pre-Modification Recorded Investment			1,946
Financing Receivable, Modifications, Post-Modification Recorded Investment			1,946
Hospitality [Member] | Financing Receivable Troubled Debt Restructurings That Subsequently Defaulted [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts			0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment			0
SBA Loans [Member] | NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts			1		2
Financing Receivable, Modifications, Pre-Modification Recorded Investment			64		1,680
Financing Receivable, Modifications, Post-Modification Recorded Investment			64		1,680
SBA Loans [Member] | Financing Receivable Troubled Debt Restructurings That Subsequently Defaulted [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts			1		0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment			55		0
Real Estate Mortgage Other Receivable [Member] | NonCovered [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts			23	14	8
Financing Receivable, Modifications, Pre-Modification Recorded Investment			17,443	16,223	14,861
Financing Receivable, Modifications, Post-Modification Recorded Investment			17,444	16,223	13,840
Real Estate Mortgage Other Receivable [Member] | Financing Receivable Troubled Debt Restructurings That Subsequently Defaulted [Member] | Mortgage Loans on Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts			0	2	0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment			$0	$1,844	$0

Loans_and_Leases_Details_8

Loans and Leases (Details 8) (USD $)	3 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2012	Dec. 31, 2014	Dec. 31, 2013
Purchased Credit Impaired Loans Composition [Line Items]
Non-PCI nonaccrual loans				$83,621	$46,774
Loans and Leases Receivable, Net Reported Amount, Covered				276,792	361,003
Mortgage Loans on Real Estate [Member]
Purchased Credit Impaired Loans Composition [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount, Covered				299,660	412,791
Real Estate Construction [Member]
Purchased Credit Impaired Loans Composition [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount, Covered				7,743	12,015
Commercial Portfolio Segment [Member]
Purchased Credit Impaired Loans Composition [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount, Covered				32,904	3,021
Consumer Portfolio Segment [Member]
Purchased Credit Impaired Loans Composition [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount, Covered				332	424
Purchased Credit Impaired Loans and Leases [Member]
Purchased Credit Impaired Loans Composition [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount, Covered				340,639	428,251
Loan Discounts				-49,848	-45,455
Loans and Leases Receivable, Allowance, Covered			-26,069	-13,999	-21,793
Loans and Leases Receivable, Net Reported Amount, Covered				276,792	361,003
NonCovered [Member]
Purchased Credit Impaired Loans Composition [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	129	1,600	921
Non-PCI nonaccrual loans					$3,929,556

Loans_and_LeasesDetails_9

Loans and Leases(Details 9) (Purchased Credit Impaired Loans and Leases [Member], Covered [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount, Net	$276,792	$361,003	$491,816	$674,058
Accretable yield	-106,856	-139,568	-196,022	-259,265
Carrying Amount [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Additions	79,234	44,146	49,562
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Accretion	57,213	46,680	-232,623
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Disposals of Loans	-219,641	-225,849	0
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Allowance for Loan Losses, Decreases	0	0	819
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Provision for Loan Losses	-1,017	4,210
Accretable Yield [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Additions	-13,728	-8,096	49,562
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Accretion	57,213	46,680	0
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Disposals of Loans	0	0	13,681
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Allowance for Loan Losses, Decreases	-10,773	17,870	0
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Provision for Loan Losses	$0	$0

Loans_and_Leases_Loans_and_Lea1

Loans and Leases Loans and Leases (Details 10) (CapitalSource Inc. [Member], Purchased Credit Impaired Loans and Leases [Member], USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
CapitalSource Inc. [Member] | Purchased Credit Impaired Loans and Leases [Member]
Accretable Yield on Purchased Credit Impaired Loans [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Acquired During Period, Contractually Required Payments Receivable at Acquisition	$231,832
Accretable yield	13,728
Certain Loans Acquired in Transfer, Nonaccretable Difference	-138,870
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Acquired During Period, Cash Flows Expected to be Collected at Acquisition	92,962
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Acquired During Period, at Acquisition, at Fair Value	($79,234)

Loans_and_Leases_Details_11

Loans and Leases (Details 11) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	$290,791	$382,796
Nonclassified [Member]
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	158,503	221,060
Classified [Member]
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	132,288	161,736
Purchased Credit Impaired Loans and Leases [Member]
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	290,852	382,796
Mortgage Loans on Real Estate [Member]
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	256,489	371,134
Loans And Leases PCI Net Of Discounts And Earned Income	256,442	371,134
Mortgage Loans on Real Estate [Member] | Nonclassified [Member]
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	155,281	216,092
Mortgage Loans on Real Estate [Member] | Classified [Member]
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	101,161	155,042
Real Estate Construction [Member]
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	6,924	10,427
Loans And Leases PCI Net Of Discounts And Earned Income	6,911	10,427
Real Estate Construction [Member] | Nonclassified [Member]
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	3,010	4,399
Real Estate Construction [Member] | Classified [Member]
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	3,901	6,028
Commercial Portfolio Segment [Member]
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	27,155	974
Loans And Leases PCI Net Of Discounts And Earned Income	27,154	974
Commercial Portfolio Segment [Member] | Nonclassified [Member]
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	212	569
Commercial Portfolio Segment [Member] | Classified [Member]
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	26,942	405
Consumer Portfolio Segment [Member]
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	284	261
Loans And Leases PCI Net Of Discounts And Earned Income	284	261
Consumer Portfolio Segment [Member] | Nonclassified [Member]
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	0	0
Consumer Portfolio Segment [Member] | Classified [Member]
Financing Receivable Recorded Investment By Credit Risk [Line Items]
Loans And Leases Net Of Discounts Covered	$284	$261

Loans_and_Leases_Details_Textu

Loans and Leases (Details Textual) (USD $)	12 Months Ended	3 Months Ended		12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2012	Dec. 31, 2013		Apr. 07, 2014
Financing Receivable, Impaired [Line Items]
Unfunded Commitments For Troubled Debt Restructurings	$214,000				$7,000
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	0				0
Loans held for investment, net	11,882,432,000				4,312,352,000
Loans and Leases Receivable, Gross	11,904,684,000				4,313,335,000
Financing Receivable Recorded Investment Thirty to Eighty Nine Days Past Due	8,700,000				4,200,000
Financing Receivable Recorded Investment Nonaccrual Status Current	56,100,000				37,300,000
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	7,500,000
NonCovered [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	83,621,000
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	18,818,000				5,233,000
Loans held for investment, net	11,591,641,000				3,929,556,000	[1]
Loans and Leases Receivable, Gross	11,613,832,000				3,930,539,000
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down		129,000	1,600,000	921,000
Financing Receivable Recorded Investment Thirty to Eighty Nine Days Past Due	19,406,000				23,897,000
Non Purchased Credit Impaired Loans and Leases [Member] | Covered [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	61,500,000				85,900,000
Purchased Credit Impaired Loans and Leases [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	290,791,000				382,796,000	[1]
Purchased Credit Impaired Loans and Leases [Member] | Covered [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	100,400,000				362,500,000
Nonperforming Financing Receivable [Member] | NonCovered [Member]
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Gross					46,774,000
Nonperforming Financing Receivable [Member] | NonCovered [Member] | Commercial Real Estate Construction Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Loans held for investment, net	1,178,000				2,830,000
Capitalsource, Inc. [Member] | NonCovered [Member]
Financing Receivable, Impaired [Line Items]
Business Combination, Acquired Receivables, Fair Value							6,800,000,000
Business Combination, Acquired Receivables, Gross Contractual Amount							9,400,000,000
Undiscounted Cash Flows Not Expected to be collected							839,800,000
Capitalsource, Inc. [Member] | Covered [Member]
Financing Receivable, Impaired [Line Items]
Business Combination, Acquired Receivables, Fair Value							$79,200,000
[1]	(1)As of December 31, 2013, the amounts of loans covered by loss sharing provisions of FDIC loss sharing agreements in the Non-PCI and PCI categories were $85.9 million and $362.5 million.

Foreclosed_Assets_Foreclosed_A2

Foreclosed Assets Foreclosed Assets (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Other Real Estate Owned Net	$35,423		$51,837
Other Foreclosed Assets	8,298		4,054
Foreclosed assets, net	43,721	[1]	55,891	[1]	56,414	81,918
NonCovered [Member] | Commercial Real Estate [Member]
Other Real Estate Owned Net	2,449
NonCovered [Member] | Construction and Land Development [Member]
Other Real Estate Owned Net	24,759
NonCovered [Member] | Multi Family [Member]
Other Real Estate Owned Net	4,823
NonCovered [Member] | Residential Mortgage [Member]
Other Real Estate Owned Net	3,392
Covered [Member] | Commercial Real Estate [Member]
Other Real Estate Owned Net			15,753
Covered [Member] | Construction and Land Development [Member]
Other Real Estate Owned Net			35,063
Covered [Member] | Multi Family [Member]
Other Real Estate Owned Net			835
Covered [Member] | Residential Mortgage [Member]
Other Real Estate Owned Net			186
Covered [Member]
Foreclosed assets, net	$9,300		$9,000
[1]	(1)As of December 31, 2014 and 2013, the amounts of covered foreclosed assets were $9.3 million and $9.0 million.

Foreclosed_Assets_Foreclosed_A3

Foreclosed Assets Foreclosed Assets (Details 1) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Other Real Estate [Roll Forward]
Foreclosed assets, net	$55,891	[1]	$56,414		$81,918
SEC Schedule III, Real Estate, Acquisitions Through Foreclosures	9,806		19,470		40,207
Provision for Other Real Estate Owned and Foreclosed Assets	7,307		2,515		14,333
Other Real Estate Owned Foreclosed Assets CORES	-21,051	[2]	-31,289	[2]	-53,828	[2]
Foreclosed Asset Payments Due To Third Parties	0		39		889
Foreclosed assets, net	43,721	[1]	55,891	[1]	56,414
Capitalsource, Inc. [Member]
Other Real Estate [Roll Forward]
Other Foreclosed Assets Acquired	$6,382		$13,772		$1,561
[1]	(1)As of December 31, 2014 and 2013, the amounts of covered foreclosed assets were $9.3 million and $9.0 million.
[2]	(1) Represents amounts due to participants and for guarantees, property taxes or other prior lien positions.

Foreclosed_Assets_Foreclosed_A4

Foreclosed Assets Foreclosed Assets (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Foreclosed Assets Rollforward [Abstract]
Foreclosed Assets Valuation Allowance	$11,314	$16,681	$20,575
Provision for Other Real Estate Owned and Foreclosed Assets	7,307	2,515	14,333
Foreclosed Assets, Valuation Allowance, Amounts Applied	-6,498	-7,882	-19,103
Foreclosed Assets Valuation Allowance Selling Costs	0	0	876	[1]
Foreclosed Assets Valuation Allowance	$12,123	$11,314	$16,681
[1]	(1) During 2011, the FDIC changed its methodology such that selling costs are reimbursed at the time of sale rather than at the time of foreclosure. Such amounts will be realized when the related OREO parcels are sold.

Foreclosed_Assets_Foreclosed_A5

Foreclosed Assets Foreclosed Assets Textuals (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Other Real Estate Owned Net Covered and NonCovered Including Foreclosed Assets [Abstract]
Foreclosed assets, net	$43,721	[1]	$55,891	[1]	$56,414	$81,918
Covered [Member]
Other Real Estate Owned Net Covered and NonCovered Including Foreclosed Assets [Abstract]
Foreclosed assets, net	$9,300		$9,000
[1]	(1)As of December 31, 2014 and 2013, the amounts of covered foreclosed assets were $9.3 million and $9.0 million.

FDIC_Loss_Sharing_Asset_FDIC_L2

FDIC Loss Sharing Asset FDIC Loss Sharing Asset (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
FDIC Indemnification Asset [Roll Forward]
Balance, beginning of year	$45,524	$57,475	$95,187
Addition from the FCAL acquisition	0	17,241	0
FDIC share of additional losses, net of recoveries	-4,941	4,969	6,169
Cash paid to (received from) FDIC	3,202	-7,332	-33,223
Net amortization	-25,051	-26,829	-10,658
Balance, end of year	$18,734	$45,524	$57,475

FDIC_Loss_Sharing_Asset_FDIC_L3

FDIC Loss Sharing Asset FDIC Loss Sharing Asset (Details1) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule of FDIC Loss Sharing Asset [Line Items]
FDIC loss sharing asset	$18,734	$45,524	$57,475	$95,187
True‑up liability	7,186
Non-single family covered assets (1)	231,057
Single family covered assets	98,395
Affinity Bank [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
FDIC loss sharing asset	-302
Non-single family covered assets (1)	113,361
Single family covered assets	10,987
Los Padres Bank [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
FDIC loss sharing asset	9,435
Non-single family covered assets (1)	77,814
Single family covered assets	56,891
Western Commercial Bank [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
FDIC loss sharing asset	1,165
True‑up liability	1,753
Non-single family covered assets (1)	11,327
San Luis Trust Bank [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
FDIC loss sharing asset	8,436
True‑up liability	5,433
Non-single family covered assets (1)	28,555
Single family covered assets	$30,517

FDIC_Loss_Sharing_Asset_FDIC_L4

FDIC Loss Sharing Asset FDIC Loss Textual (Details) (Below threshold [Member], Affinity Bank [Member])	12 Months Ended
	Dec. 31, 2014
Below threshold [Member] | Affinity Bank [Member]
Schedule of FDIC Loss Sharing Asset [Line Items]
FDIC Indemnification rate on covered assets	80.00%

Premises_and_Equipment_Net_Pre1

Premises and Equipment, Net Premises and Equipment, Net (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Premises and Equipment, Net [Abstract]
Land	$5,505	$6,755
Buildings and Improvements, Gross	14,198	12,725
Furniture and Fixtures, Gross	32,359	31,080
Leasehold Improvements, Gross	33,157	26,091
Property, Plant and Equipment, Gross	85,219	76,651
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	-48,668	-44,216
Property, Plant and Equipment, Net	$36,551	$32,435

Premises_and_Equipment_Net_Pre2

Premises and Equipment, Net Premises and Equipment, Net (Details 1) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Premises and Equipment, Net [Abstract]
2015	$26,767
2016	22,978
2017	20,009
2018	17,293
2019	13,626
Thereafter	43,943
Total	$144,616

Premises_and_Equipment_Net_Det

Premises and Equipment, Net (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Premises and Equipment, Net [Abstract]
Depreciation, Depletion and Amortization	$8,400,000	$6,000,000	$5,400,000
Operating Leases, Rent Expense	23,800,000	17,600,000	16,800,000
Operating Leases, Income Statement, Lease Revenue	589,000	750,000	505,000
Future Minimum Sublease Rentals, Sale Leaseback Transactions	$29,300,000

Deposits_Deposits_Details

Deposits Deposits (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Deposits [Abstract]
Interest checking deposits	$736,367	$620,622
Money market deposits	1,825,510	1,458,910
Savings deposits	762,961	218,638
Time deposits under $100,000	2,467,338	225,360
Time deposits $100,000 and over	3,031,600	439,011
Total interest-bearing deposits	$8,823,776	$2,962,541

Deposits_Deposits_Details_1

Deposits Deposits (Details 1) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Time Deposits Balance [Line Items]
Time Deposit Maturities, Next Twelve Months	$4,958,460
Time Deposits, Weighted Average Interest Rate, Maturities Year One	0.72%
Time Deposit Maturities, Year Two	424,658
Time Deposits, Weighted Average Interest Rate, Maturities Year Two	1.01%
Time Deposit Maturities, Year Three	68,825
Time Deposits, Weighted Average Interest Rate, Maturities Year Three	0.84%
Time Deposit Maturities, Year Four	35,339
Time Deposits, Weighted Average Interest Rate, Maturities Year Four	1.13%
Time Deposit Maturities, Year Five	11,346
Time Deposits, Weighted Average Interest Rate, Maturities Year Five	1.03%
Time Deposit Maturities, after Year Five	310
Time Deposits, Weighted Average Interest Rate, Maturities Greater than Five Years	0.78%
Time Deposits	5,498,938	664,371
Weighted Average Rate Domestic Deposit, Time Deposits	0.75%
Time Deposits Under $100,000
Time Deposits Balance [Line Items]
Time Deposit Maturities, Next Twelve Months	2,233,704
Time Deposit Maturities, Year Two	176,125
Time Deposit Maturities, Year Three	32,047
Time Deposit Maturities, Year Four	20,272
Time Deposit Maturities, Year Five	4,880
Time Deposit Maturities, after Year Five	310
Time Deposits	2,467,338
Time Deposits $100,000 Or More
Time Deposits Balance [Line Items]
Time Deposit Maturities, Next Twelve Months	2,724,756
Time Deposit Maturities, Year Two	248,533
Time Deposit Maturities, Year Three	36,778
Time Deposit Maturities, Year Four	15,067
Time Deposit Maturities, Year Five	6,466
Time Deposit Maturities, after Year Five	0
Time Deposits	$3,031,600

Deposits_Details

Deposits (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Time Deposits Balance [Line Items]
Interest-bearing Domestic Deposit, Brokered	$636.70	$49.40
Certificate of Deposit Account Registry Service Program [Member]
Time Deposits Balance [Line Items]
Interest-bearing Domestic Deposit, Brokered	$44	$49.40

Borrowings_and_Subordinated_De2

Borrowings and Subordinated Debentures (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Borrowings	$383,402,000	$113,726,000
Notes Payable, Other Payables [Member]
Debt Instrument [Line Items]
Non-Recourse Debt	3,402,000	7,126,000
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	6.43%	0.00%
Federal Home Loan Bank Advances [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Amount Outstanding	$380,000,000	$106,600,000
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	0.27%	0.00%

Borrowings_and_Subordinated_De3

Borrowings and Subordinated Debentures Borrowings and Subordinated Debentures (Details 1) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Subordinated Borrowing [Line Items]
Subordinated debentures	$433,583		$132,645
Subordinated Debt Trust V Due September 2033 [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross	10,310		10,310
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	3.33%	[1]	3.34%	[2]
Debt Instrument Date Issued	15-Aug-03
Debt Instrument, Maturity Date	17-Sep-33
Debt Instrument, Basis Spread on Variable Rate	3 month LIBOR + 3.10
Subordinated Debt Trust VI Due September 2033 [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross	10,310		10,310
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	3.29%	[1]	3.29%	[2]
Debt Instrument Date Issued	3-Sep-03
Debt Instrument, Maturity Date	15-Sep-33
Debt Instrument, Basis Spread on Variable Rate	3 month LIBOR + 3.05
Subordinated Debt Trust CII Due September 2033 [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross	5,155		5,155
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	3.19%	[1]	3.19%	[2]
Debt Instrument Date Issued	17-Sep-03
Debt Instrument, Maturity Date	17-Sep-33
Debt Instrument, Basis Spread on Variable Rate	3 month LIBOR + 2.95
Subordinated Debt Trust VII Due April 2034 [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross	61,856		61,856
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	2.98%	[1]	2.99%	[2]
Debt Instrument Date Issued	5-Feb-04
Debt Instrument, Maturity Date	23-Apr-34
Debt Instrument, Basis Spread on Variable Rate	3 month LIBOR + 2.75
Subordinated Debt Trust CIII Due September 2035 [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross	20,619		20,619
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	1.93%	[1]	1.93%	[2]
Debt Instrument Date Issued	15-Aug-05
Debt Instrument, Maturity Date	15-Sep-35
Debt Instrument, Basis Spread on Variable Rate	3 month LIBOR + 1.69
Subordinated Debt Trust FCCI Due March 2037 [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross	16,495		16,495
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	1.84%	[1]	1.84%	[2]
Debt Instrument Date Issued	25-Jan-07
Debt Instrument, Maturity Date	15-Mar-37
Debt Instrument, Basis Spread on Variable Rate	3 month LIBOR + 1.60
Subordinated Debt Trust FCBI Due December 2035 [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross	10,310		10,310
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	1.79%	[1]	1.79%	[2]
Debt Instrument Date Issued	30-Sep-05
Debt Instrument, Maturity Date	15-Dec-35
Debt Instrument, Basis Spread on Variable Rate	3 month LIBOR + 1.55
Trust Preferred Securities Two Thousand Five Series One [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross	82,475	[3]
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	2.19%	[1],[3]
Debt Instrument Date Issued	21-Nov-05
Debt Instrument, Maturity Date	15-Dec-35
Debt Instrument, Basis Spread on Variable Rate	3 month LIBOR + 1.95
Trust Preferred Securities Two Thousand Five Series Two [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross	128,866	[3]
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	2.18%	[1],[3]
Debt Instrument Date Issued	14-Dec-05
Debt Instrument, Maturity Date	30-Jan-36
Debt Instrument, Basis Spread on Variable Rate	3 month LIBOR + 1.95
Two Thousand Six One Term Debt Securitization [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross	51,545	[3]
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	2.18%	[1],[3]
Debt Instrument Date Issued	22-Feb-06
Debt Instrument, Maturity Date	30-Apr-36
Debt Instrument, Basis Spread on Variable Rate	3 month LIBOR + 1.95
Two Thousand Six Two Term Debt Securitization [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross	51,550	[3]
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	2.18%	[1],[3]
Debt Instrument Date Issued	27-Sep-06
Debt Instrument, Maturity Date	30-Oct-36
Debt Instrument, Basis Spread on Variable Rate	3 month LIBOR + 1.95
Trust Preferred Securities Two Thousand Six Series Three [Member]
Subordinated Borrowing [Line Items]
Liability, Reporting Currency Denominated, Value	25,800	[4]
Long-term Debt, Gross	31,188	[3],[4]
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	2.14%	[1],[3]
Debt Instrument Date Issued	29-Sep-06
Debt Instrument, Maturity Date	30-Oct-36
Debt Instrument, Basis Spread on Variable Rate	3 month EURIBOR + 2.05
Trust Preferred Securities Two Thousand Six Series Four [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross	16,470	[3]
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	2.18%	[1],[3]
Debt Instrument Date Issued	5-Dec-06
Debt Instrument, Maturity Date	30-Jan-37
Debt Instrument, Basis Spread on Variable Rate	3 month LIBOR + 1.95
Trust Preferred Securities Two Thousand Six Series Five [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross	6,650	[3]
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	2.18%	[1],[3]
Debt Instrument Date Issued	19-Dec-06
Debt Instrument, Maturity Date	30-Jan-37
Debt Instrument, Basis Spread on Variable Rate	3 month LIBOR + 1.95
Two Thousand Seven One Term Debt Securitization [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross	39,177	[3]
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	2.18%	[1],[3]
Debt Instrument Date Issued	13-Jun-07
Debt Instrument, Maturity Date	30-Jul-37
Debt Instrument, Basis Spread on Variable Rate	3 month LIBOR + 1.95
Subordinated Debt [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross	542,976		135,055
Debt Instrument, Unamortized Discount	-109,393	[5]	-2,410
Subordinated debentures	$433,583		$132,645
[1]	(1)As of December 31, 2014.
[2]	(2)As of January 28, 2014.
[3]	(3)Acquired in the CapitalSource Inc. merger.
[4]	(4)Denomination is in Euros with a value of €25.8 million.
[5]	(5)Amount represents the fair value adjustment on trust preferred securities assumed in the CapitalSource Inc. and FCAL acquisitions.

Borrowings_and_Subordinated_De4

Borrowings and Subordinated Debentures (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Interest-bearing Domestic Deposit, Brokered	636,700,000	$49,400,000
Federal Reserve Bank Advances [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Amount Outstanding		0
Notes Payable, Other Payables [Member]
Debt Instrument [Line Items]
Debt Instruments Weighted Average Remaining Maturity Period	2 years 3 months 18 days
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Borrowing Capacity, Description	75,000,000
Line of Credit Facility, Amount Outstanding	0
Federal Home Loan Bank Advances [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Current Borrowing Capacity	2,400,000,000
Line of Credit Facility, Amount Outstanding	380,000,000	106,600,000
Unsecured Debt [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Borrowing Capacity, Description	80,000,000
Unused lines of Credit [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Amount Outstanding	0	0
Certificate of Deposit Account Registry Service Program [Member]
Debt Instrument [Line Items]
Interest-bearing Domestic Deposit, Brokered	44,000,000	49,400,000
Federal Home Loan Bank of San Francisco [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Borrowing Capacity, Description	1,300,000,000
Loans Pledged as Collateral	1,800,000,000
Line of Credit Facility, Amount Outstanding	0

Commitments_and_Contingencies_1

Commitments and Contingencies Details (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]
Loan commitments to extend credit	$1,921,067	$1,001,740
Standby letters of credit	88,495	39,200
Commitments to purchase equipment being acquired for lease to others	12,839	8,475
Fair Value Disclosure, Off-balance Sheet Risks, Amount, Liability	$2,022,401	$1,049,415

Commitments_and_Contingencies_2

Commitments and Contingencies (Details Textual) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Long-term Purchase Commitment [Line Items]
Commitment To Contribute Capital	$11	$11
Private Equity Funds [Member]
Long-term Purchase Commitment [Line Items]
Purchase Commitment, Remaining Minimum Amount Committed		$2.90
Number of funds		11

Fair_Value_Measurements_Detail

Fair Value Measurements (Details 1) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Securities available‑for‑sale	$1,567,177	$1,494,745
Derivative Asset, Fair Value of Collateral	5,234
Derivative Liability, Fair Value of Collateral	118
Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	1,567,177	1,494,745
Derivative Asset, Fair Value of Collateral	5,234
Assets, Fair Value Disclosure, Recurring	1,572,411
Derivative Liability, Fair Value of Collateral	118
Level 1
Securities available‑for‑sale		507
Derivative Asset, Fair Value of Collateral	0
Derivative Liability, Fair Value of Collateral	0
Level 1 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	519	507
Derivative Asset, Fair Value of Collateral	0
Assets, Fair Value Disclosure, Recurring	519
Derivative Liability, Fair Value of Collateral	0
Level 2
Securities available‑for‑sale		1,456,334
Derivative Asset, Fair Value of Collateral	5,234
Derivative Liability, Fair Value of Collateral	118
Level 2 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	1,532,711	1,456,334
Derivative Asset, Fair Value of Collateral	5,234
Assets, Fair Value Disclosure, Recurring	1,537,945
Derivative Liability, Fair Value of Collateral	118
Level 3
Securities available‑for‑sale		37,904
Derivative Asset, Fair Value of Collateral	0
Derivative Liability, Fair Value of Collateral	0
Level 3 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	33,947	37,904
Derivative Asset, Fair Value of Collateral	0
Assets, Fair Value Disclosure, Recurring	33,947
Derivative Liability, Fair Value of Collateral	0
Government agency and government-sponsored enterprise pass through securities | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	535,672	707,188
Government agency and government-sponsored enterprise pass through securities | Level 1 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	0	0
Government agency and government-sponsored enterprise pass through securities | Level 2 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	535,672	707,188
Government agency and government-sponsored enterprise pass through securities | Level 3 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	0	0
Government agency and government-sponsored enterprise collateralized mortgage obligations [Member] | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	277,946	192,873
Government agency and government-sponsored enterprise collateralized mortgage obligations [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	0	0
Government agency and government-sponsored enterprise collateralized mortgage obligations [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	277,946	192,873
Government agency and government-sponsored enterprise collateralized mortgage obligations [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	0	0
Covered private label collateralized mortgage obligation [Member] | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	33,947	37,904
Covered private label collateralized mortgage obligation [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	0	0
Covered private label collateralized mortgage obligation [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	0	0
Covered private label collateralized mortgage obligation [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	33,947	37,904
Other Private Label Collateralized Mortgage Obligations [Member]
Securities available‑for‑sale		0
Other Private Label Collateralized Mortgage Obligations [Member] | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	10,914
Other Private Label Collateralized Mortgage Obligations [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	0
Other Private Label Collateralized Mortgage Obligations [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	10,914
Other Private Label Collateralized Mortgage Obligations [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	0
Municipal securities | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	536,116	436,658
Municipal securities | Level 1 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	0	0
Municipal securities | Level 2 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	536,116	436,658
Municipal securities | Level 3 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	0	0
Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	110,109	82,707
Corporate Debt Securities [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	0	0
Corporate Debt Securities [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	110,109	82,707
Corporate Debt Securities [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	0	0
US Government-sponsored Enterprises Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	36,757	9,872
US Government-sponsored Enterprises Debt Securities [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	0	0
US Government-sponsored Enterprises Debt Securities [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	36,757	9,872
US Government-sponsored Enterprises Debt Securities [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	0	0
Other securities [Member] | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	25,716	27,543
Other securities [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	519	507
Other securities [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	25,197	27,036
Other securities [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Securities available‑for‑sale	$0	$0

Fair_Value_Measurements_Fair_V

Fair Value Measurements Fair Value Measurements (Details 2) (Level 3, Private Label CMOs, Fair Value, Measurements, Recurring [Member])	12 Months Ended
	Dec. 31, 2014
Minimum [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value Inputs, Prepayment Rate	0.00%
Fair Value Inputs, Probability of Default	0.00%
Fair Value Inputs, Loss Severity	0.00%
Fair Value Inputs, Discount Rate	0.00%
Maximum [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value Inputs, Prepayment Rate	36.40%
Fair Value Inputs, Probability of Default	38.00%
Fair Value Inputs, Loss Severity	68.60%
Fair Value Inputs, Discount Rate	6.70%
Weighted Average [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value Inputs, Prepayment Rate	6.30%
Fair Value Inputs, Probability of Default	2.30%
Fair Value Inputs, Loss Severity	24.00%
Fair Value Inputs, Discount Rate	4.90%

Fair_Value_Measurements_Fair_V1

Fair Value Measurements Fair Value Measurements (Details 3) (Covered Private Label Collateralized Mortgage Obligations Member [Domain], Fair Value, Measurements, Recurring [Member], Level 3, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014
Covered Private Label Collateralized Mortgage Obligations Member [Domain] | Fair Value, Measurements, Recurring [Member] | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings	$1,627	$1,938	$340
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	-344	-1,204	4,883
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	-5,240	-7,514	-5,688
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$37,904	$44,684	$45,149	$33,947

Fair_Value_Measurements_Fair_V2

Fair Value Measurements Fair Value Measurements (Details 4) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure	$11,757,951	$4,231,078
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure		0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure		2,051
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure	11,755,585	4,229,027
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	67,274	51,763
Fair Value, Measurements, Nonrecurring [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	20,766	10,835
Fair Value, Measurements, Nonrecurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	46,508	40,928
Non Purchased Credit Impaired Loans and Leases [Member] | Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	42,693	40,886
Non Purchased Credit Impaired Loans and Leases [Member] | Fair Value, Measurements, Nonrecurring [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring		0
Loans Receivable, Fair Value Disclosure	0
Non Purchased Credit Impaired Loans and Leases [Member] | Fair Value, Measurements, Nonrecurring [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring		2,051
Loans Receivable, Fair Value Disclosure	2,366
Non Purchased Credit Impaired Loans and Leases [Member] | Fair Value, Measurements, Nonrecurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	40,327	38,835
Other real estate and foreclosed assets [Member] | Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	24,015	10,877
Other real estate and foreclosed assets [Member] | Fair Value, Measurements, Nonrecurring [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	0	0
Other real estate and foreclosed assets [Member] | Fair Value, Measurements, Nonrecurring [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	18,400	8,784
Cost-method Investments [Member] | Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	566
Cost-method Investments [Member] | Fair Value, Measurements, Nonrecurring [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	0
Cost-method Investments [Member] | Fair Value, Measurements, Nonrecurring [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	0
Third party appraisals [Domain] | Non Purchased Credit Impaired Loans and Leases [Member] | Fair Value, Measurements, Nonrecurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	4,178
Third party appraisals [Domain] | Other real estate and foreclosed assets [Member] | Fair Value, Measurements, Nonrecurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	5,615	2,093
Third party appraisals [Domain] | Cost-method Investments [Member] | Fair Value, Measurements, Nonrecurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	$566

Fair_Value_Measurements_Fair_V3

Fair Value Measurements Fair Value Measurements (Details 5) (Fair Value, Measurements, Nonrecurring [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Net Gain (Loss) from Nonrecurring Assets	($13,884)	($2,251)	($9,502)
Other real estate and foreclosed assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Net Gain (Loss) from Nonrecurring Assets	-6,737	-1,045	-3,920
Non Purchased Credit Impaired Loans and Leases [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Net Gain (Loss) from Nonrecurring Assets	-7,006	-1,206	-5,582
Cost-method Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Net Gain (Loss) from Nonrecurring Assets	($141)	$0	$0

Fair_Value_Measurements_Fair_V4

Fair Value Measurements Fair Value Measurements (Details 6) (Fair Value, Measurements, Nonrecurring [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	67,274	$51,763
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	46,508	40,928
Non Purchased Credit Impaired Loans and Leases [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	42,693	40,886
Non Purchased Credit Impaired Loans and Leases [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	40,327	38,835
Other real estate and foreclosed assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	24,015	10,877
Cost-method Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	566
Discounted Cash Flow [Member] | Non Purchased Credit Impaired Loans and Leases [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	36,149
Third party appraisals [Domain] | Non Purchased Credit Impaired Loans and Leases [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	4,178
Third party appraisals [Domain] | Other real estate and foreclosed assets [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	5,615	2,093
Third party appraisals [Domain] | Cost-method Investments [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	566
Minimum [Member] | Discounted Cash Flow [Member] | Non Purchased Credit Impaired Loans and Leases [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	0.00%
Minimum [Member] | Third party appraisals [Domain] | Non Purchased Credit Impaired Loans and Leases [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	0.00%
Minimum [Member] | Third party appraisals [Domain] | Other real estate and foreclosed assets [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	24.00%
Minimum [Member] | Market Approach Valuation Technique [Member] | Cost-method Investments [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Illiquidity Discount	0.00%
Maximum [Member] | Discounted Cash Flow [Member] | Non Purchased Credit Impaired Loans and Leases [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	12.17%
Maximum [Member] | Third party appraisals [Domain] | Non Purchased Credit Impaired Loans and Leases [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	0.00%
Maximum [Member] | Third party appraisals [Domain] | Other real estate and foreclosed assets [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	38.00%
Maximum [Member] | Market Approach Valuation Technique [Member] | Cost-method Investments [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Illiquidity Discount	0.00%
Weighted Average [Member] | Discounted Cash Flow [Member] | Non Purchased Credit Impaired Loans and Leases [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	5.92%
Weighted Average [Member] | Third party appraisals [Domain] | Non Purchased Credit Impaired Loans and Leases [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	0.00%
Weighted Average [Member] | Third party appraisals [Domain] | Other real estate and foreclosed assets [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	35.00%
Weighted Average [Member] | Market Approach Valuation Technique [Member] | Cost-method Investments [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Illiquidity Discount	75.00%

Fair_Value_Measurements_Fair_V5

Fair Value Measurements Fair Value Measurements (Details 7) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	$164,757	$96,424
Interest-earning deposits in financial institutions	148,469	50,998
Available-for-sale Securities	1,567,177	1,494,745
Federal Home Loan Bank stock, at cost	40,609	27,939
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure	40,609	27,939
Cost Method Investments	3,691
Cost Method Investments, Fair Value Disclosure	3,691
Equity Method Investments	21,461
Equity Method Investments, Fair Value Disclosure	21,700
Loans and leases, net	11,797,977	4,230,318
Loans Receivable, Fair Value Disclosure	11,757,951	4,231,078
Derivative Asset	5,234
Derivative Asset, Fair Value of Collateral	5,234
Deposits, Savings Deposits	6,256,190	4,616,616
Time Deposits	5,498,938	664,371
Deposits, Fair Value Disclosure	5,202,464	665,148
Borrowed Funds	383,402	113,726
Long-term Debt, Fair Value	383,539	113,726
Subordinated debentures	433,583	132,645
Subordinated Debt Obligations, Fair Value Disclosure	417,657	132,498
Derivative Liability	118
Derivative Liability, Fair Value of Collateral	118
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	164,757	96,424
Interest-earning deposits in financial institutions	148,469	50,998
Available-for-sale Securities		507
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure	0	0
Cost Method Investments, Fair Value Disclosure	0
Equity Method Investments, Fair Value Disclosure	0
Loans Receivable, Fair Value Disclosure		0
Derivative Asset, Fair Value of Collateral	0
Deposits, Savings Deposits	0	0
Deposits, Fair Value Disclosure	0	0
Long-term Debt, Fair Value	380,000	106,600
Subordinated Debt Obligations, Fair Value Disclosure	0	0
Derivative Liability, Fair Value of Collateral	0
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	0	0
Interest-earning deposits in financial institutions	0	0
Available-for-sale Securities		1,456,334
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure	40,609	27,939
Cost Method Investments, Fair Value Disclosure	0
Equity Method Investments, Fair Value Disclosure	0
Loans Receivable, Fair Value Disclosure		2,051
Derivative Asset, Fair Value of Collateral	5,234
Deposits, Savings Deposits	6,256,190	4,616,616
Deposits, Fair Value Disclosure	5,202,464	665,148
Long-term Debt, Fair Value	3,539	7,126
Subordinated Debt Obligations, Fair Value Disclosure	417,657	132,498
Derivative Liability, Fair Value of Collateral	118
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	0	0
Interest-earning deposits in financial institutions	0	0
Available-for-sale Securities		37,904
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure	0	0
Cost Method Investments, Fair Value Disclosure	3,691
Equity Method Investments, Fair Value Disclosure	21,700
Loans Receivable, Fair Value Disclosure	11,755,585	4,229,027
Derivative Asset, Fair Value of Collateral	0
Deposits, Savings Deposits	0	0
Deposits, Fair Value Disclosure	0	0
Long-term Debt, Fair Value	0	0
Subordinated Debt Obligations, Fair Value Disclosure	0	0
Derivative Liability, Fair Value of Collateral	$0

Fair_Value_Measurements_Fair_V6

Fair Value Measurements Fair Value Measurements (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other than Temporary Impairment Losses, Investments, Portion in Other Comprehensive Loss, Tax, Portion Attributable to Parent	$0	$0	($1,115,000)
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	0	0	1,115,000
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount	0
Threshold for loans that are considered individually significant for allowance analysis purposes	250,000
Non-PCI nonaccrual loans	83,621,000	46,774,000
Non-PCI nonaccrual loans write downs based on collateral values	$4,400,000

Income_Taxes_Income_Taxes_Deta

Income Taxes Income Taxes (Details 1) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Federal	($11,459)	($29,591)	($24,177)
Current State and Local Tax Expense	-10,823	-7,667	-1,825
Current Income Tax Expense	-22,282	-37,258	-26,002
Deferred Federal Income Tax Expense	-70,662	9,099	-2,550
Deferred State and Local Income Tax Expense	-19,795	-1,586	-8,143
Deferred Income Tax Expense (Benefit)	-90,457	7,513	-10,693
Income Tax Expense (Benefit), Continuing Operations, Discontinued Operations, Extraordinary Items	($112,739)	($29,745)	($36,695)

Income_Taxes_Income_Taxes_Deta1

Income Taxes Income Taxes (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount	($98,575)	($26,201)	($32,724)
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount	-15,689	-6,014	-6,479
Effective Income Tax Rate Reconciliation, Tax Exempt Income, Amount	4,472	3,979	1,847
Income Tax Reconciliation Change In Cash Surrender Value Of Life Insurance	739	407	442
Effective Income Tax Rate Reconciliation, Tax Credit, Amount	3,567	2,480	1,313
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Amount	-6,792	-4,730	-322
Nondeductible acquisition-related expense	-2,994	-1,196	-532
Income Tax Reconciliation Acquisition Related Securities Gain Loss	0	1,828	0
Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount	2,533	-298	-240
Income Tax Expense (Benefit), Continuing Operations, Discontinued Operations, Extraordinary Items	$112,739	$29,745	$36,695

Income_Taxes_Income_Taxes_Deta2

Income Taxes Income Taxes (Details 3) (USD $)	Dec. 31, 2014	Apr. 07, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Income Tax Disclosure [Abstract]
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Provision for Loan Losses	$100,981		$45,840
Interest on nonaccrual loans	7,394		444
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Compensation	4,585		4,541
Deferred Tax Assets, Property, Plant and Equipment	5,359		3,643
Deferred tax assets, unrealized losses on other real estate owned	7,353		9,784
Assets acquired in FDIC-assisted acquisition	10,217		16,375
Deferred Tax Assets, State Taxes	5,009		2,368
Deferred Tax Assets, Operating Loss Carryforwards	207,575		197
Deferred Tax Assets, Capital Loss Carryforwards	57,494		0
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities	36,115		16,629
Deferred Tax Assets, Other	6,254		8,084
Deferred Tax Assets, Equity Method Investments	8,666		568
Deferred Tax Assets, Goodwill and Intangible Assets	44,372		6,595
Deferred Tax Assets, Deferred Income	0		378
Tax Credit Carryforward, Deferred Tax Asset	32,183		0
Deferred Tax Assets, Unrealized Losses on Available-for-Sale Securities, Gross	0		2,424
Deferred Tax Assets, Gross	533,557		117,870
Deferred Tax Assets, Valuation Allowance	-130,282	-130,700	0
Deferred Tax Assets, Net of Valuation Allowance	403,275		117,870
Deferred Tax Liabilities, Goodwill and Intangible Assets	3,978		6,022
Deferred Tax Liabilities, Tax Deferred Income	17,594		0
Deferred Tax Liabilities, Other Comprehensive Income	17,926		0
Deferred Tax Liabilities, Regulatory Assets	2,820		7,123
Deferred Tax Liabilities, Subordinated Debt	40,369		1,003
Deferred Tax Liabilities, Leasing Arrangements	34,136		0
Unrealized income from FDIC-assisted acquisition	2,041		24,086
Deferred Tax Liabilities, Gross	118,864		38,234
Deferred Tax Assets, Net	$284,411		$79,636

Income_Taxes_Income_Taxes_Deta3

Income Taxes Income Taxes (Details 4) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2012
Reconciliation of Unrecognized Tax Benefits [Roll Forward]
Balance, December 31, 2013	$0	$0
Increase related to CapitalSource Inc. merger	18,724,000
Increase based on tax positions related to prior years	2,371,000
Reductions related to settlements	-293,000
Reductions for tax positions as a result of a lapse of the applicable statute of limitations	-301,000
Balance, December 31, 2014	$20,501,000	$0

Income_Taxes_Income_Taxes_Deta4

Income Taxes Income Taxes (Details Textuals) (USD $)	12 Months Ended
	Dec. 31, 2014	Apr. 07, 2014	Dec. 31, 2013	Dec. 31, 2012
Increase related to CapitalSource Inc. merger	$18,724,000
Statutory Federal Income Tax Rate	35.00%
Income Taxes Receivable	18,300,000		39,600,000
Deferred Tax Assets, Valuation Allowance	130,282,000	130,700,000	0
Unused Federal operating loss carryforwards	446,400,000
Unused State operating loss carryforwards	936,300,000
Unused Federal capital loss carryforwards	135,800,000
Low Income Housing Tax Credit carryforwards	3,300,000
Tax Credit Carryforward, Expiration Date	31-Dec-34
Unrecognized Tax Benefits	20,501,000		0	0
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	2,400,000
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	2,000,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	200,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	3,300,000
Minimum [Member]
Unused Federal operating loss carryforward expiration date	1/1/30
State operating loss carryforwards expiration date	12/31/15
Federal capital loss carryforward expiration date	1/1/15
Foreign tax credit carryforward expiration date	1-Jan-16
Open Tax Year	2006
Maximum [Member]
Unused Federal operating loss carryforward expiration date	12/31/31
State operating loss carryforwards expiration date	12/31/33
Federal capital loss carryforward expiration date	12/31/19
Foreign tax credit carryforward expiration date	31-Dec-21
Open Tax Year	2013
CapitalSource Inc. [Member]
Unused Federal capital loss carryforwards	132,400,000
Deferred Tax Assets, Tax Credit Carryforwards, Foreign	28,600,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	$3,100,000
State and Local Jurisdiction [Member] | Minimum [Member]
Income Tax Examination, Year under Examination	2006
State and Local Jurisdiction [Member] | Maximum [Member]
Income Tax Examination, Year under Examination	2012
Internal Revenue Service (IRS) [Member] | Minimum [Member]
Income Tax Examination, Year under Examination	2008
Internal Revenue Service (IRS) [Member] | Maximum [Member]
Income Tax Examination, Year under Examination	2012

Earnings_Per_Share_Details

Earnings Per Share (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
Earnings Per Share [Abstract]
Income (Loss) from Continuing Operations Attributable to Parent									$170,468		$45,477		$56,801
Less: earnings allocated to unvested restricted stock(1)									-1,959	[1]	-1,096	[1]	-1,845	[1]
Net earnings from continuing operations allocated to common shares									168,509		44,381		54,956
Net (loss) earnings from discontinued operations allocated to common shares									-1,545		-348		0
Net earnings allocated to common shares									$166,964		$44,033		$54,956
Weighted-average basic shares and unvested restricted stock outstanding									87,871		42,506		37,370
Less: weighted-average unvested restricted stock outstanding									-1,018		-1,683		-1,685
Weighted-average basic shares outstanding									86,853		40,823		35,685
Net earnings from continuing operations	$690	$600	$110	$570	$70	$530	$110	$370	$1.94		$1.09		$1.54
Net loss from discontinued operations									($0.02)		($0.01)		$0
Basic net income per share (usd per share)	$690	$600	$100	$550	$60	$530	$110	$370	$1.92		$1.08		$1.54
Net earnings allocated to common shares									166,964		44,033		54,956
Net earnings from continuing operations	$690	$600	$110	$570	$70	$530	$110	$370	$1.94		$1.09		$1.54
Net loss from discontinued operations									($0.02)		($0.01)		$0
Diluted net income per share (usd per share)	$690	$600	$100	$550	$60	$530	$110	$370	$1.92		$1.08		$1.54
[1]	(1)Represents cash dividends paid to holders of unvested restricted stock, net of estimated forfeitures, plus undistributed earnings amounts available to holders of unvested restricted stock, if any.

Stock_Based_Compensation_Plan_1

Stock Based Compensation Plan Stock-based Compensation Plan (Details 1) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Number of Shares
Beginning balance	1,216,524	1,698,281	1,675,730
Granted	1,129,805	673,900	226,400
Shares issued by the Company upon vesting	-1,183,024	-819,461	-195,871
Forfeited	-54,800	-336,196	-7,978
Ending balance	1,108,505	1,216,524	1,698,281
Weighted Average Grant Date Fair Value (Per Share)
Beginning balance	$28.69	$30.68	$30.53
Granted	$40.37	$29.06	$23.77
Shares issued by the Company upon vesting	$28.53	$24.84	$21.69
Forfeited	$38.97	$48.92	$22.31
Ending balance	$40.37	$28.69	$30.68

Stock_Based_Compensation_Plan_2

Stock Based Compensation Plan Stock-based Compensation Plan (Details 2) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	1,129,805		673,900	226,400
Equity Instruments Other than Options, Nonvested, Number	1,108,505		1,216,524	1,698,281	1,675,730
Shares issued by the Company upon vesting	$28.53		$24.84	$21.69
Granted	$40.37		$29.06	$23.77
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	1,081,505		27,000
Restricted stock awarded and earned stock compensation, net of shares forfeited	$49,165		$1,228
Equity Instruments Other than Options, Nonvested, Number	1,108,505
Shares issued by the Company upon vesting	$40.37		$35.08
Granted	$50,393,000	[1]
Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms	1 year 6 months 37 days		1 year 6 months 37 days
[1]	(1)Determined using the $45.46 closing price of PacWest common stock on December 31, 2014.

Stock_Based_Compensation_Plan_3

Stock Based Compensation Plan Stock-based Compensation Plan (Details Textual) (USD $)	12 Months Ended				0 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012	Apr. 07, 2014	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity Instruments Other than Options, Nonvested, Number	1,108,505		1,216,524	1,698,281		1,675,730
Vesting period of time-based restricted stock, lower limit	3 years
Vesting period of time-based restricted stock, higher limit	4 years
Awarded shares of restricted common stock vested due to the triggering of the change of control provision contained within the 2003 Plan	1,013,377
Expense incurred due to awarded shares of restricted common stock vested due to the triggering of the change of control provision contained within the 2003 Plan	$26.10
Share Price	$45.46	[1]
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity Instruments Other than Options, Nonvested, Number	1,108,505
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	53.4		30.9	4.5
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options	36
Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms	1 year 6 months 37 days		1 year 6 months 37 days
Restricted Stock [Member] | Vesting Based On Service [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	9.8		8.5	5.7
Share-based Compensation Arrangement by Share-based Payment Award Accelerated Compensation Cost	26.1		12.4
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$3.90		$3.40	$2.20
PacWest 2003 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	19,686,565
Share-based compensation arrangement, number of Shares Authorized due to CapitalSource, Inc Plan	10,686,565
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	13,531,719
Share-based compensation arrangement, Number of Shares Available for Grant due to CapitalSource, Inc Compensation Plan	10,107,039
Capitalsource, Inc. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Business Acquisition, Effective Date of Acquisition	7-Apr-14				7-Apr-14
[1]	(1)Determined using the $45.46 closing price of PacWest common stock on December 31, 2014.

Benefit_Plans_Details_Textuals

Benefit Plans (Details Textuals) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
	Y
Benefit Plans [Abstract]
Minimum Hours Of Work Required By Participants	1,000
Minimum Age Of Work Required By Participants	21
Maximum Annual Contributions Per Employee, Percent	60.00%
Cost Recognized	$1.90	$1.30	$1

Stockholders_Equity_Details_Te

Stockholders' Equity (Details Textuals) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Shares, Outstanding	103,022,017	45,822,834	37,420,909	37,254,318
Treasury Stock, Shares, Acquired	493,890	351,640	63,681
Capitalsource, Inc. [Member]
Expiration of Dividend Reinvestment Program	30-Apr-15
Proceeds from (Repurchase of) Equity	0
Repurchased common stock from dividend reinvestment program	2,583

Dividend_Availability_and_Regu2

Dividend Availability and Regulatory Matters (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	4.00%
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	4.00%
Tier One Leverage Capital	$1,722,870	$718,800
Tier One Leverage Capital to Average Assets	12.34%	11.22%
Tier One Leverage Capital Required to be Well Capitalized	698,109	320,405
Tier One Leverage Capital Required to be Well Capitalized to Average Assets	5.00%	5.00%
Excess Tier One Leverage Capital	1,024,761	398,395
Tier One Risk Based Capital	1,722,870	718,800
Tier One Risk Based Capital to Risk Weighted Assets	13.16%	15.12%
Tier One Risk Based Capital Required to be Well Capitalized	785,781	285,163
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	6.00%	6.00%
Excess Tier One Risk Based Capital	937,089	433,637
Capital	2,104,984	778,582
Capital to Risk Weighted Assets	16.07%	16.38%
Capital Required to be Well Capitalized	1,309,635	475,271
Excess Capital	795,349	303,311
Pacific Western Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier One Leverage Capital	1,621,546	690,440
Tier One Leverage Capital to Average Assets	11.70%	10.79%
Tier One Leverage Capital Required to be Well Capitalized	693,174	319,999
Excess Tier One Leverage Capital	928,372	370,441
Tier One Risk Based Capital	1,621,546	690,440
Tier One Risk Based Capital to Risk Weighted Assets	12.46%	14.54%
Tier One Risk Based Capital Required to be Well Capitalized	780,834	284,825
Excess Tier One Risk Based Capital	840,712	405,615
Capital	1,712,312	750,152
Capital to Risk Weighted Assets	13.16%	15.80%
Capital Required to be Well Capitalized	1,301,390	474,708
Capital Required to be Well Capitalized to Risk Weighted Assets	10.00%	10.00%
Excess Capital	$410,922	$275,444

Dividend_Availability_and_Regu3

Dividend Availability and Regulatory Matters Textuals (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Proceeds from Dividends Received	$137,000,000
Capital Required for Capital Adequacy to Risk Weighted Assets	8.00%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	4.00%
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	4.00%
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	6.00%	6.00%
Tier One Leverage Capital Required to be Well Capitalized to Average Assets	5.00%	5.00%
Deferred Tax Assets, Regulatory Assets and Liabilities	156,700,000
Subordinated debentures	433,583,000	132,645,000
Proceeds from Issuance of Trust Preferred Securities	131,000,000
Pacific Western Bank [Member]
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Capital Required to be Well Capitalized to Risk Weighted Assets	10.00%	10.00%
Deferred Tax Assets, Regulatory Assets and Liabilities	0
Subordinated Debt [Member]
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Subordinated debentures	433,583,000	132,645,000
CapitalSource Inc. [Member] | Subordinated Debt [Member]
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Subordinated debentures	$300,400,000

Business_Segment_Segment_Repor

Business Segment Segment Reporting (Details 1) (USD $)	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Loans held for investment, net	$11,882,432		$4,312,352
Loans and Leases Receivable, Allowance	-84,455		-82,034
Total loans and leases, net	11,797,977		4,230,318
Goodwill	1,720,479	[1]	208,743	[1]	79,866	39,141
Core deposit and customer relationship intangibles, net	17,204		17,248
Total assets	16,234,800		6,533,363
Total deposits	11,755,128	[2]	5,280,987	[2]
Operating Segments [Member] | Pacific Western Bank [Member]
Loans held for investment, net	3,401,129		3,837,475
Loans and Leases Receivable, Allowance	-48,253		-75,498
Total loans and leases, net	3,352,876		3,761,977
Goodwill	326,078	[1]	183,065	[1]
Core deposit and customer relationship intangibles, net	16,306		15,331
Total assets	6,512,313		6,004,067
Total deposits	12,030,436	[2]	5,302,822	[2]
Operating Segments [Member] | National Lending Segment [Member]
Loans held for investment, net	8,455,849		474,877
Loans and Leases Receivable, Allowance	-36,202		-6,536
Total loans and leases, net	8,419,647		468,341
Goodwill	1,394,401	[1]	25,678	[1]
Core deposit and customer relationship intangibles, net	898		1,917
Total assets	9,483,601		519,675
Total deposits	33,179	[2]	0	[2]
Operating Segments [Member] | Other Segments [Member]
Loans held for investment, net	25,454		0
Loans and Leases Receivable, Allowance	0		0
Total loans and leases, net	25,454		0
Goodwill	0	[1]	0	[1]
Core deposit and customer relationship intangibles, net	0		0
Total assets	238,886		9,621
Total deposits	($308,487)	[2]	($21,835)	[2]
[1]	(1)The increase in the goodwill for the Community Banking segment and National Lending segment during 2014 was due primarily to $1.5 billion from the CapitalSource merger.
[2]	(2)The negative balance for total deposits in the “Other” segment represents the elimination of holding company cash held in deposit accounts at the Bank.

Business_Segment_Details_2

Business Segment (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 [Line Items]
Interest Income	$209,696	$202,356	$204,363	$88,360					$704,775	$309,914	$296,115
Interest expense	-14,713	-13,510	-11,830	-2,345	-2,598	-2,869	-3,158	-3,576	-42,398	-12,201	-19,648
Intersegment interest income (expense), net									0	0	0
Net interest income	194,983	188,846	192,533	86,015	81,258	82,289	68,473	65,693	662,377	297,713	276,467
Provision for credit losses	-2,063	-5,050	-5,030	644	1,338	4,167	1,842	-3,137	-11,499	4,210	12,819
Gain on securities	0	0	89	4,752	-272	5,222	0	409	4,841	5,359	1,239
FDIC loss sharing expense, net	-4,360	-7,415	-8,525	-11,430	-10,593	-7,032	-5,410	-3,137	-31,730	-26,172	-10,070
Other noninterest income	17,063	23,729	16,915	11,369	6,939	6,937	5,613	5,568	69,076	25,057	24,703
Total non-interest income	12,703	16,314	8,479	4,691	-3,926	5,127	203	2,840	42,187	4,244	15,872
Foreclosed assets (expense) income, net	-1,938	-4,827	-497	1,861	569	420	14	500	-5,401	1,503	-10,931
Intangible asset amortization	-7,381	-5,193	-86,242	-2,200	-16,673	-5,450	-17,997	-692	-6,268	-5,402	-6,326
Acquisition, integration and reorganization costs	-83,021	-85,609	-83,167	-50,530	-49,984	-51,170	-46,233	-43,991	-101,016	-40,812	-4,089
Debt Termination Expenses											-22,598
Other noninterest expense					-66,088	-56,200	-64,216	-44,183	-296,059	-185,976	-167,718
Total noninterest expense	-92,340	-95,629	-169,906	-50,869					-408,744	-230,687	-211,662
Income (Loss) from Continuing Operations Attributable to Parent									170,468	45,477	56,801
Intersegment noninterest income (expense_									0
Total noninterest expense - adjusted									-408,744
Earnings (loss) from continuing operations before taxes	113,283	104,481	26,076	40,481	12,582	35,383	6,302	21,213	284,321	75,480	93,496
Income Tax Expense (Benefit)	-42,226	-42,205	-14,846	-14,576	-9,135	-11,243	-1,906	-7,719	-113,853	-30,003	-36,695
Net earnings from continuing operations	71,057	62,276	11,230	25,905	3,447	24,140	4,396	13,494	170,468	45,477
Loss from discontinued operations before taxes	-105	-8	-1,151	-1,413	-578	39	-81	0	-2,677	-620	0
Income tax benefit	47	3	476	588	240	-16	34	0	1,114	258	0
Net loss from discontinued operations	-58	-5	-675	-825	-338	23	-47	0	-1,563	-362	0
Net earnings	70,999	62,271	10,555	25,080	3,109	24,163	4,349	13,494	168,905	45,115	56,801
Operating Segments [Member] | Pacific Western Bank [Member]
Segment Reporting Information [Line Items]
Interest Income									279,671	261,492	251,720
Interest expense									-27,598	-7,873	-15,043
Intersegment interest income (expense), net									15,716	1,525	2,055
Net interest income									267,789	255,144	238,732
Provision for credit losses									21,311	8,079	14,585
Gain on securities									4,841	137	1,239
FDIC loss sharing expense, net									-31,730	-26,172	-10,070
Other noninterest income									25,168	21,395	20,572
Total non-interest income									-1,721	-4,640	11,741
Foreclosed assets (expense) income, net									-5,685	1,503	-10,931
Intangible asset amortization									-5,745	-4,748	-5,898
Acquisition, integration and reorganization costs									-89,888	-40,552	-4,089
Debt Termination Expenses											-24,195
Other noninterest expense									-198,921	-156,600	-138,640
Total noninterest expense									-300,239	-200,397	-183,753
Intersegment noninterest income (expense_									71,897
Total noninterest expense - adjusted									-228,342
Earnings (loss) from continuing operations before taxes									59,037	58,186	81,305
Income Tax Expense (Benefit)									-27,370	-24,940	-31,542
Net earnings from continuing operations									31,667	33,246
Loss from discontinued operations before taxes									-2,677	-620
Income tax benefit									1,114	258
Net loss from discontinued operations									-1,563	-362
Net earnings									30,104	32,884	49,763
Operating Segments [Member] | National Lending Segment [Member]
Segment Reporting Information [Line Items]
Interest Income									422,677	48,422	44,395
Interest expense									-230	-532	-884
Intersegment interest income (expense), net									-15,716	-1,525	-2,055
Net interest income									406,731	46,365	41,456
Provision for credit losses									-32,810	-3,869	-1,766
Gain on securities									0	0	0
FDIC loss sharing expense, net									0	0	0
Other noninterest income									34,215	3,558	4,017
Total non-interest income									34,215	3,558	4,017
Foreclosed assets (expense) income, net									-302	0	0
Intangible asset amortization									-523	-654	-428
Acquisition, integration and reorganization costs									-10,073	0	0
Other noninterest expense									-80,418	-23,575	-23,502
Total noninterest expense									-91,316	-24,229	-23,930
Intersegment noninterest income (expense_									-71,897
Total noninterest expense - adjusted									-163,213
Earnings (loss) from continuing operations before taxes									244,923	21,825	19,777
Income Tax Expense (Benefit)									-97,853	-9,101	-8,327
Net earnings from continuing operations									147,070	12,724
Loss from discontinued operations before taxes									0	0
Income tax benefit									0	0
Net loss from discontinued operations									0	0
Net earnings									147,070	12,724	11,450
Operating Segments [Member] | Other Segments [Member]
Segment Reporting Information [Line Items]
Interest Income									2,427	0	0
Interest expense									-14,570	-3,796	-3,721
Intersegment interest income (expense), net									0	0	0
Net interest income									-12,143	-3,796	-3,721
Provision for credit losses									0	0	0
Gain on securities									0	5,222	0
FDIC loss sharing expense, net									0	0	0
Other noninterest income									9,693	104	114
Total non-interest income									9,693	5,326	114
Foreclosed assets (expense) income, net									586	0	0
Intangible asset amortization									0	0	0
Acquisition, integration and reorganization costs									-1,055	-260	0
Debt Termination Expenses											1,597
Other noninterest expense									-16,720	-5,801	-5,576
Total noninterest expense									-17,189	-6,061	-3,979
Intersegment noninterest income (expense_									0
Total noninterest expense - adjusted									-17,189
Earnings (loss) from continuing operations before taxes									-19,639	-4,531	-7,586
Income Tax Expense (Benefit)									11,370	4,038	3,174
Net earnings from continuing operations									-8,269	-493
Loss from discontinued operations before taxes									0	0
Income tax benefit									0	0
Net loss from discontinued operations									0	0
Net earnings									($8,269)	($493)	($4,412)

Business_Segment_Business_Segm

Business Segment Business Segment (Details Textuals) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2014		Dec. 31, 2012	Dec. 31, 2013		Dec. 31, 2011
Segment Reporting (Textuals) [Abstract]
Goodwill		$1,720,479	[1]	$79,866	$208,743	[1]	$39,141
Goodwill, Acquired During Period		$1,518,381		$19,033
Date of asset-based lending companies reorganization & sale of Celtic Corporation	1-Jul-14
[1]	(1)The increase in the goodwill for the Community Banking segment and National Lending segment during 2014 was due primarily to $1.5 billion from the CapitalSource merger.

Condensed_Financial_Informatio2

Condensed Financial Information Of Parent Company Parent Company Information (Details 1) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Condensed Financial Statements, Captions [Line Items]
Cash	$313,226	$147,422
Other assets	272,205	193,462
Total assets	16,234,800	6,533,363
Subordinated debentures	433,583	132,645
Liabilities	12,728,375	5,724,270
Stockholders' Equity Attributable to Parent Only	3,506,425	809,093	589,121	546,203
Liabilities and Equity	16,234,800	6,533,363
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Cash	309,220	21,835
Investments In Consolidated Banking Subsidiaries	3,119,642	911,200
Other assets	212,157	10,341
Total assets	3,641,019	943,376
Subordinated debentures	133,232	132,645
Other Liabilities	1,362	1,638
Liabilities	134,594	134,283
Stockholders' Equity Attributable to Parent Only	3,506,425	809,093
Liabilities and Equity	$3,641,019	$943,376

Condensed_Financial_Informatio3

Condensed Financial Information Of Parent Company Parent Company 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
Condensed Financial Statements, Captions [Line Items]
Investment Income, Dividend									$3,613	$1,604	$446
Interest Expense	14,713	13,510	11,830	2,345	2,598	2,869	3,158	3,576	42,398	12,201	19,648
Net earnings from continuing operations	71,057	62,276	11,230	25,905	3,447	24,140	4,396	13,494	170,468	45,477
Income Tax Expense (Benefit)	42,226	42,205	14,846	14,576	9,135	11,243	1,906	7,719	113,853	30,003	36,695
Net earnings	70,999	62,271	10,555	25,080	3,109	24,163	4,349	13,494	168,905	45,115	56,801
Parent Only
Condensed Financial Statements, Captions [Line Items]
Other Income									122	104	114
Acquisition Related Securities Gain									0	5,222	0
Debt Termination Income									0	0	1,597
Investment Income, Dividend									137,000	48,000	50,000
Total Income									137,122	53,326	51,711
Interest Expense									4,211	3,796	3,721
Operating Expenses									8,105	6,061	5,576
Total Expenses									12,316	9,857	9,297
Net earnings from continuing operations									124,806	43,469	42,414
Income Tax Expense (Benefit)									5,164	4,038	3,174
Income Loss From Continuing Operations Before Income Loss From Equity Method Investments									129,970	47,507	45,588
Income (Loss) from Equity Method Investments, Net of Dividends or Distributions									38,935	-2,392	11,213
Net earnings									$168,905	$45,115	$56,801

Condensed_Financial_Informatio4

Condensed Financial Information Of Parent Company Parent Company Information (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	Dec. 31, 2011
Condensed Financial Statements, Captions [Line Items]
Net earnings	$70,999	$62,271	$10,555	$25,080	$3,109	$24,163	$4,349	$13,494	$168,905	$45,115	$56,801
Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract]
Decrease (increase) in other assets									22,708	-9,403	18,754
Tax effect included in stockholders' equity of restricted stock vesting									-4,625	-2,133	-283
Earned stock compensation									36,474	21,246	5,999
Net Cash Provided by (Used in) Operating Activities, Continuing Operations									332,110	50,252	117,980
Net Cash Provided by (Used in) Investing Activities [Abstract]
Cash acquired in acquisitions, net of cash consideration paid									346,047	273,013	-87,098
Payments to Acquire Available-for-sale Securities									-236,739	-550,211	-485,860
Net Cash Provided by (Used in) Financing Activities [Abstract]
Tax effect included in stockholders' equity of restricted vesting stock									4,625	2,133	283
Restricted stock surrendered									-22,307	-13,537	-1,475
Cash dividends paid, net									-114,162	-41,006	-28,787
Net Cash Provided by (Used in) Financing Activities, Continuing Operations									-722,864	-480,173	-420,114
Net Cash Provided by (Used in) Continuing Operations									165,804	-16,982	-131,213
Cash and Cash Equivalents, at Carrying Value	313,226				147,422				313,226	147,422	164,404	295,617
Supplemental Cash Flow Information [Abstract]
Common stock ($0.01 par value, 200,000,000 and 75,000,000 shares authorized at December 31, 2014 and 2013; 104,219,197 and 46,526,124 shares issued, respectively, includes 1,108,505 and 1,216,524 shares of unvested restricted stock, respectively)	1,042				465				1,042	465
Parent Only
Condensed Financial Statements, Captions [Line Items]
Net earnings									168,905	45,115	56,801
Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract]
Acquisition Related Securities Gain									0	-5,222	0
Decrease (increase) in other assets									39,874	-609	711
Increase (Decrease) in Operating Liabilities									310	4,932	-4,122
Tax effect included in stockholders' equity of restricted stock vesting									4,625	-364	-102
Earned stock compensation									41,099	441	715
Income (Loss) from Equity Method Investments, Net of Dividends or Distributions									-38,935	2,392	-11,213
Net Cash Provided by (Used in) Operating Activities, Continuing Operations									215,878	46,685	42,790
Net Cash Provided by (Used in) Investing Activities [Abstract]
Cash acquired in acquisitions, net of cash consideration paid									226,960	857	0
Payments to Acquire Available-for-sale Securities									0	0	-1,500
Net Cash Provided by (Used in) Investing Activities, Continuing Operations									226,960	857	-1,500
Net Cash Provided by (Used in) Financing Activities [Abstract]
Repayments of Subordinated Debt									0	0	-18,558
Tax effect included in stockholders' equity of restricted vesting stock									-4,625	364	102
Restricted stock surrendered										-13,537	-1,475
Cash dividends paid, net									-114,162	-41,006	-28,787
Net Cash Provided by (Used in) Financing Activities, Continuing Operations									-141,094	-54,179	-48,718
Net Cash Provided by (Used in) Continuing Operations									301,744	-6,637	-7,428
Cash and Cash Equivalents, at Carrying Value	323,579				21,835				323,579	21,835	28,472	35,900
Supplemental Cash Flow Information [Abstract]
Common stock ($0.01 par value, 200,000,000 and 75,000,000 shares authorized at December 31, 2014 and 2013; 104,219,197 and 46,526,124 shares issued, respectively, includes 1,108,505 and 1,216,524 shares of unvested restricted stock, respectively)					$242,268					$242,268	$0

Selected_Quarterly_Financial_D2

Selected Quarterly Financial Data Selected Quarterly Financial Data (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
Interest Income (Expense), Net [Abstract]
Interest Income	$209,696	$202,356	$204,363	$88,360					$704,775	$309,914	$296,115
Interest expense	-14,713	-13,510	-11,830	-2,345	-2,598	-2,869	-3,158	-3,576	-42,398	-12,201	-19,648
Net interest income	194,983	188,846	192,533	86,015	81,258	82,289	68,473	65,693	662,377	297,713	276,467
Provision (negative provision) for credit losses	-2,063	-5,050	-5,030	644	1,338	4,167	1,842	-3,137	-11,499	4,210	12,819
FDIC loss sharing expense, net	-4,360	-7,415	-8,525	-11,430	-10,593	-7,032	-5,410	-3,137	-31,730	-26,172	-10,070
Noninterest Income [Abstract]
Gain on securities	0	0	89	4,752	-272	5,222	0	409	4,841	5,359	1,239
Noninterest Income, Other	17,063	23,729	16,915	11,369	6,939	6,937	5,613	5,568	69,076	25,057	24,703
Total non-interest income	12,703	16,314	8,479	4,691	-3,926	5,127	203	2,840	42,187	4,244	15,872
Noninterest Expense [Abstract]
Foreclosed assets (expense) income, net	-1,938	-4,827	-497	1,861	569	420	14	500	-5,401	1,503	-10,931
Additions	-7,381	-5,193	-86,242	-2,200	-16,673	-5,450	-17,997	-692	-6,268	-5,402	-6,326
Acquisition, integration and reorganization costs	-83,021	-85,609	-83,167	-50,530	-49,984	-51,170	-46,233	-43,991	-101,016	-40,812	-4,089
Total noninterest expense	-92,340	-95,629	-169,906	-50,869					-408,744	-230,687	-211,662
Income (Loss) from Continuing Operations Attributable to Parent [Abstract]
Earnings from continuing operations before taxes	113,283	104,481	26,076	40,481	12,582	35,383	6,302	21,213	284,321	75,480	93,496
Income Tax Expense (Benefit)	-42,226	-42,205	-14,846	-14,576	-9,135	-11,243	-1,906	-7,719	-113,853	-30,003	-36,695
Net earnings from continuing operations	71,057	62,276	11,230	25,905	3,447	24,140	4,396	13,494	170,468	45,477
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent [Abstract]
Loss from discontinued operations before taxes	-105	-8	-1,151	-1,413	-578	39	-81	0	-2,677	-620	0
Income tax benefit	47	3	476	588	240	-16	34	0	1,114	258	0
Net loss from discontinued operations	-58	-5	-675	-825	-338	23	-47	0	-1,563	-362	0
Net earnings	$70,999	$62,271	$10,555	$25,080	$3,109	$24,163	$4,349	$13,494	$168,905	$45,115	$56,801
Earnings Per Share, Basic [Abstract]
Net earnings from continuing operations	$690	$600	$110	$570	$70	$530	$110	$370	$1.94	$1.09	$1.54
Basic net income per share (usd per share)	$690	$600	$100	$550	$60	$530	$110	$370	$1.92	$1.08	$1.54
Earnings Per Share, Diluted [Abstract]
Net earnings from continuing operations	$690	$600	$110	$570	$70	$530	$110	$370	$1.94	$1.09	$1.54
Diluted net income per share (usd per share)	$690	$600	$100	$550	$60	$530	$110	$370	$1.92	$1.08	$1.54

Related_Party_Transaction_Rela

Related Party Transaction Related Party Transaction (Details) (USD $)	0 Months Ended	12 Months Ended	0 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Apr. 07, 2014	Dec. 31, 2014	31-May-13	Aug. 01, 2012	Dec. 31, 2012
Capitalsource, Inc. [Member]
Related Party Transaction [Line Items]
Business Acquisition, Effective Date of Acquisition	7-Apr-14	7-Apr-14
Capitalsource, Inc. [Member] | Castle Creek Finance LLC [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction		9,000
First California Financial Group, Inc. [Member]
Related Party Transaction [Line Items]
Business Acquisition, Effective Date of Acquisition			31-May-13
First California Financial Group, Inc. [Member] | Castle Creek Finance LLC [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction		1,300
American Perspective Bank [Member]
Related Party Transaction [Line Items]
Business Acquisition, Effective Date of Acquisition				1-Aug-12
American Perspective Bank [Member] | Castle Creek Finance LLC [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction					$448

Subsequent_Events_Subsequent_E

Subsequent Events Subsequent Events (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Subsequent Event [Line Items]
Dividends declared per share (usd per share)	$1.25	$1	$0.79
Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends Payable, Date Declared	11-Feb-15
Dividends Payable, Date to be Paid	5-Mar-15
Dividends Payable, Date of Record	23-Feb-15
Dividend Declared [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends declared per share (usd per share)	$0.50