Columbia Banking System (COLB) 10-Q 6 May 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2015	Apr. 30, 2015
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Mar-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Entity Registrant Name	COLUMBIA BANKING SYSTEM INC
Entity Central Index Key	887343
Current Fiscal Year End Date	-19
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		57,692,047

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Mar. 31, 2015		Dec. 31, 2014
In Thousands, unless otherwise specified
ASSETS
Cash and due from banks	$177,026		$171,221
Interest-earning deposits with banks	71,575		16,949
Total cash and cash equivalents	248,601		188,170
Securities available for sale at fair value (amortized cost of $1,981,977 and $2,087,069, respectively)	2,007,159		2,098,257
Federal Home Loan Bank stock at cost	33,004		33,365
Loans held for sale	3,545		1,116
Loans, net of unearned income of ($53,867) and ($59,374), respectively	5,450,895		5,445,378
Loans and Leases Receivable, Allowance	70,234		69,569
Loans, net	5,380,661		5,375,809
FDIC loss sharing asset	14,644		15,174
Interest receivable	29,088		27,802
Premises and equipment, net	172,958		172,090
Other real estate owned	23,299		22,190
Goodwill	382,537		382,537
Other intangible assets, net	28,642		30,459
Other assets	228,764		231,877
Total Assets	8,552,902		8,578,846
LIABILITIES AND SHAREHOLDERS' EQUITY
Noninterest-bearing	3,260,376		2,651,373
Interest-bearing	3,814,589		4,273,349
Total deposits	7,074,965		6,924,722
Federal Home Loan Bank advances	36,559		216,568
Securities sold under agreements to repurchase	96,852		105,080
Other Borrowings	0		8,248
Other liabilities	100,083		96,053
Total liabilities	7,308,459		7,350,671
Commitments and contingent liabilities
Shareholders' equity:
Preferred Stock, Shares Authorized	2,000		2,000
Preferred Stock, Shares Issued	9		9
Preferred Stock, Value, Issued	2,217		2,217
Authorized shares	63,033		63,033
Common Stock Shares Issued And Outstanding	57,699		57,437
Common Stock (no par value)	986,348		985,839
Retained earnings	241,592		234,498
Accumulated other comprehensive income	14,286	[1]	5,621	[1]
Total shareholders' equity	1,244,443		1,228,175
Total Liabilities and Shareholders' Equity	$8,552,902		$8,578,846
[1]	All amounts are net of tax. Amounts in parenthesis indicate debits.

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, except Per Share data, unless otherwise specified
Securities available-for-sale, amortized cost	$1,981,977	$2,087,069
Less: Unearned income on loans	-53,867	-59,374
Loans and Leases Receivable, Allowance	70,234	69,569
Other real estate owned covered by FDIC loss share	$23,299	$22,190
Common stock, par value	$0	$0
Authorized shares	63,033	63,033
Common stock, shares outstanding	57,699	57,437

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Net of tax	$24,361		$19,844
Unrealized gain from securities:
Net unrealized holding loss from available for sale securities arising during the period	9,376		7,119
Reclassification adjustment of net gain from sale of available for sale securities included in income	-459		-142
Net unrealized gain from securities, net of reclassification adjustment	8,917		6,977
Pension plan liability adjustment:
Unrecognized net actuarial gain (loss) during the period	-280		0
Less: amortization of unrecognized net actuarial loss included in net periodic pension cost	28		24
Pension plan liability adjustment, net	-252		24
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	8,665	[1]	7,001	[1]
Total comprehensive income	$33,026		$26,845
[1]	All amounts are net of tax. Amounts in parenthesis indicate debits.

Consolidated_Statements_of_Inc

Consolidated Statements of Income (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Interest Income
Loans	$70,822		$65,541
Taxable securities	7,526		6,752
Tax-exempt securities	3,042		2,618
Deposits in banks	27		14
Total interest income	81,417		74,925
Interest Expense
Deposits	748		752
Federal Home Loan Bank advances	159		114
Other borrowings	146		119
Total interest expense	1,053		985
Net Interest Income	80,364		73,940
Provision for loan and lease losses	1,209	[1]	1,922	[1]
Net interest income after provision for loan and lease losses	79,155		72,018
Noninterest Income (Loss)
Service charges and other fees	14,869		12,936
Merchant services fees	2,040		1,870
Gain (Loss) on Sale of Securities, Net	721		223
Bank owned life insurance	1,078		965
Change in FDIC loss sharing asset	150		-4,819
Other	3,909		2,833
Total noninterest income (loss)	22,767		14,008
Noninterest Expense
Compensation and employee benefits	39,100		31,338
Occupancy	7,993		8,244
Merchant processing	977		980
Advertising and promotion	931		769
Data processing and communications	4,984		3,520
Legal and professional fees	2,507		2,169
Taxes, licenses and fees	1,232		1,180
Regulatory premiums	1,221		1,176
Net cost (benefit) of operation of other real estate owned	-1,246		146
Amortization of intangibles	1,817		1,580
Other	7,218		6,284
Total noninterest expense	66,734		57,386
Income before income taxes	35,188		28,640
Income tax provision	10,827		8,796
Net Income	$24,361		$19,844
Earnings per common share
Basic ($ per share)	$0.42		$0.38
Diluted ($ per share)	$0.42		$0.37
Dividends paid per common share	$0.30		$0.12
Weighted average number of common shares outstanding	56,965		51,097
Weighted average number of diluted common shares outstanding	56,978		52,433
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Consolidated_Statements_of_Com1

Consolidated Statements of Comprehensive Income (Parenthetical) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Net unrealized holding gain (loss) from available for sale securities arising during the period, tax	($5,338)	($4,049)
Reclassification adjustment of net gain from sale of available for sale securities included in income, tax	262	0
Net unrealized loss from unfunded defined benefit plan liability arising during the period, tax	159	0
Less: amortization of unrecognized net actuarial loss included in net periodic pension cost, tax	($16)	($13)

Consolidated_Statements_of_Cha

Consolidated Statements of Changes in Shareholders' Equity (USD $)	Total	Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]	Preferred Stock [Member]
In Thousands
Balance, value at Dec. 31, 2013	$1,053,249	$860,562	$202,514	($12,044)	$2,217
Balance, shares at Dec. 31, 2013		51,265			9
Net Income	19,844		19,844
Other comprehensive income	7,001			7,001
Issuance of common stock - cashless exercise of warrants, shares		1,140
Issuance of common stock - cashless exercise of warrants, value	0	0
Issuance of common stock - stock option and other plans, value	405	405
Issuance of common stock - stock option and other plans, shares		19
Issuance of common stock - restricted stock awards, net of cancelled awards, value	680	680
Issuance of common stock - restricted stock awards, net of cancelled awards, shares		197
Stock Repurchased During Period, Shares		-21
Stock Repurchased and Retired During Period, Value	-522	-522
Dividends, Preferred Stock, Cash	-12
Cash dividends paid on common stock	-6,154		-6,154
Balance, value at Mar. 31, 2014	1,074,491	861,125	216,192	-5,043	2,217
Balance, shares at Mar. 31, 2014		52,600			9
Balance, value at Dec. 31, 2014	1,228,175	985,839	234,498	5,621	2,217
Balance, shares at Dec. 31, 2014		57,437			9
Net Income	24,361		24,361
Other comprehensive income	8,665			8,665
Issuance of common stock - stock option and other plans, value	428	428
Issuance of common stock - stock option and other plans, shares		17
Issuance of common stock - restricted stock awards, net of cancelled awards, value	862	862
Issuance of common stock - restricted stock awards, net of cancelled awards, shares		273
Stock Repurchased During Period, Shares		-28
Stock Repurchased and Retired During Period, Value	-781	-781
Dividends, Preferred Stock, Cash	-31
Cash dividends paid on common stock	-17,236		-17,236
Balance, value at Mar. 31, 2015	$1,244,443	$986,348	$241,592	$14,286	$2,217
Balance, shares at Mar. 31, 2015		57,699			9

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Cash Flows From Operating Activities
Net Income	$24,361		$19,844
Adjustments to reconcile net income to net cash provided by operating activities
Provision for loan and lease losses	1,209	[1]	1,922	[1]
Stock-based compensation expense	862		680
Depreciation, amortization and accretion	7,735		8,972
Net realized gain on sale of securities	721		223
Net realized gain on sale of other assets	-306		8
Net realized (gain) loss on sale of other real estate owned	-1,736		-1,659
Write-down on other real estate owned	197		1,580
Net change in:
Loans held for sale	-2,429		735
Interest receivable	-1,286		-1,394
Interest payable	-79		-13
Other assets	-4,531		5,714
Other liabilities	3,680		-649
Net cash provided by operating activities	26,956		35,517
Cash Flows From Investing Activities
Payments for (Proceeds from) Loans and Leases	-12,443		-64,065
Purchases of securities available for sale	-11,362		-10,787
Purchases of premises and equipment	-4,032		-4,930
Proceeds from FDIC reimbursement on loss-sharing asset	1,138		539
Proceeds from sales of securities available for sale	57,243		6,441
Proceeds from principal repayments and maturities of securities available for sale	54,451		36,530
Proceeds from Sales of Assets, Investing Activities	7,745		337
Proceeds from sales of other real estate and other personal property owned	5,067	[2]	11,205	[2]
Payment to FDIC Related to Loss-Sharing Asset	-479		-2,217
Net cash provided by (used in) investing activities	97,328		-26,947
Cash Flows From Financing Activities
Net increase (decrease) in deposits	150,243		84,941
Proceeds from Federal Home Loan Bank advances	624,000		587,000
Proceeds from Federal Reserve Bank borrowings	0		50
Proceeds from exercise of stock options	428		405
Repayment of Federal Home Loan Bank advances	-804,000		-617,000
Repayment of Federal Reserve Bank borrowings	0		-50
Payment of common stock dividends	-17,236		-6,154
Payments of Ordinary Dividends, Preferred Stock and Preference Stock	-31		-12
Repayments of Subordinated Debt	8,248		0
Purchase and retirement of common stock	781		522
Net cash used by financing activities	-63,853		48,658
Increase (Decrease) in cash and cash equivalents	60,431		57,228
Cash and cash equivalents at beginning of period	188,170		179,561
Cash and cash equivalents at end of period	248,601		236,789
Supplemental Information:
Cash paid for interest	1,132		999
Cash paid for income tax	13		10
Non-cash investing and financing activities
Loans transferred to other real estate owned	4,692		5,751
Increase (Decrease) in Federal Funds Purchased and Securities Sold under Agreements to Repurchase, Net	($8,228)		$0
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[2]	Reclassified to conform to the current periodbs presentation. The reclassification was limited to removing the separate line item for bSales of covered other real estate ownedb and including the prior period activity in the line item for sales of other real estate and other personal property owned.

Basis_of_Presentation_and_Sign

Basis of Presentation and Significant Accounting Policies	3 Months Ended
	Mar. 31, 2015
Basis of Presentation And Significant Accounting Policies
Basis of Presentation and Significant Accounting Policies	Basis of Presentation and Significant Accounting Policies
	Basis of Presentation
	The interim unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America for interim financial information and with instructions to Form 10-Q and Article 10 of Regulation S-X. The consolidated financial statements include the accounts of Columbia Banking System, Inc. (“we”, “our”, “Columbia” or the “Company”) and its subsidiaries, including its wholly owned banking subsidiary Columbia State Bank (“Columbia Bank” or the “Bank”) and West Coast Trust Company, Inc. (“West Coast Trust”). All intercompany transactions and accounts have been eliminated in consolidation. In the opinion of management, all adjustments (consisting only of normal recurring adjustments) considered necessary for a fair statement of the results for the interim periods presented have been included. The results of operations for the three months ended March 31, 2015 are not necessarily indicative of results to be anticipated for the year ending December 31, 2015. The accompanying interim unaudited consolidated financial statements should be read in conjunction with the financial statements and related notes contained in the Company’s 2014 Annual Report on Form 10-K.
	Due to the timing of the acquisition of Intermountain Community Bancorp (“Intermountain”) on November 1, 2014, our results of operations for the three month period ended March 31, 2015 include the acquisition for the entire three month period, however the prior year period’s results of operations do not include the acquisition. See Note 3, Business Combinations, for further information regarding this acquisition.
	Significant Accounting Policies
	The significant accounting policies used in preparation of our consolidated financial statements are disclosed in our 2014 Annual Report on Form 10-K. There have not been any changes in our significant accounting policies compared to those contained in our 2014 Form 10-K disclosure for the year ended December 31, 2014.

Accounting_Pronouncements_Rece

Accounting Pronouncements Recently Issued	3 Months Ended
	Mar. 31, 2015
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Accounting Pronouncements Recently Issued	Accounting Pronouncements Recently Issued
	In April 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2015-05, Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement. The Update provides guidance to customers about whether a cloud computing arrangement includes a software license. If a cloud computing arrangement includes a software license, the customer should account for the software license element of the arrangement consistent with the acquisition of other software licenses. If a cloud computing arrangement does not include a software license, the customer should account for the arrangement as a service contract. The new guidance does not change the accounting for a customer’s accounting for service contracts. ASU No. 2015-05 is effective for interim and annual reporting periods beginning after December 15, 2015. The Company is currently assessing the impact that this guidance will have on its consolidated financial statements, but does not expect the guidance to have a material impact on the Company’s consolidated financial statements.
	In June 2014, the FASB issued ASU 2014-11, Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures. The Update changes the accounting for repurchase-to-maturity transactions and linked repurchase financings to secured borrowing accounting, which is consistent with accounting for other repurchase agreements. Additionally, the amendment requires new disclosures on transfers accounted for as sales in transactions that are economically similar to repurchase agreements and requires increased transparency on collateral pledged in secured borrowings. The amendments in this update will be effective for the first interim or annual period beginning after December 31, 2014, with the exception of the collateral disclosures which will be effective for interim periods beginning after March 15, 2015. Early application is not permitted. The Company does not expect the guidance to have a material impact on the Company’s consolidated financial statements.
	In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers. The guidance in this update supersedes the revenue recognition requirements in ASC Topic 605, Revenue Recognition, and most industry-specific guidance throughout the industry topics of the codification. For public companies, this update will be effective for interim and annual periods beginning after December 15, 2016. The Company is currently assessing the impact that this guidance will have on its consolidated financial statements, but does not expect the guidance to have a material impact on the Company’s consolidated financial statements.

Business_combinations

Business combinations	3 Months Ended
	Mar. 31, 2015
Business Combinations [Abstract]
Business Combination Disclosure [Text Block]	Business Combinations
	On November 1, 2014, the Company completed its acquisition of Intermountain. The Company paid $131.9 million in total consideration to acquire 100% of the equity interests of Intermountain. The primary reason for the acquisition was to expand the Company’s geographic footprint into the state of Idaho, consistent with its ongoing growth strategy.
	The assets acquired and liabilities assumed have 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 November 1, 2014 acquisition date. Initial accounting for deferred taxes was incomplete as of March 31, 2015. The amount currently recognized in the financial statements has been determined provisionally as the final Intermountain Community Bancorp tax return has not yet been completed. The fair value of the net assets acquired totaled $93.4 million, including $736.8 million of deposits, $502.6 million of loans and $10.9 million of other intangible assets. Goodwill of $38.6 million was recorded as part of the acquisition. The goodwill is not deductible for income tax purposes.
	The operating results of the Company reported herein include the operating results produced by the acquired assets and assumed liabilities for the period January 1, 2015 to March 31, 2015. Disclosure of the amount of Intermountain’s revenue and net income (excluding integration costs) included in Columbia’s consolidated income statement is impracticable due to the integration of the operations and accounting for this acquisition.
	For illustrative purposes only, the following table presents certain unaudited pro forma information for the three month period ended March 31, 2014. This unaudited pro forma information was calculated as if Intermountain had been acquired as of the beginning of the year prior to the date of acquisition. The unaudited pro forma information combines the historical results of Intermountain with the Company’s consolidated historical results and includes certain adjustments reflecting the estimated impact of certain fair value adjustments for the respective period. The pro forma information is not indicative of what would have occurred had the acquisition occurred as of the beginning of the year prior to the acquisition. In particular, no adjustments have been made to eliminate the impact of other-than-temporary impairment losses and losses recognized on the sale of securities that may not have been necessary had the investment securities been recorded at fair value as of the beginning of the year prior to the date of acquisition. The unaudited pro forma information does not consider any changes to the provision for credit losses resulting from recording loan assets at fair value. Additionally, Columbia expects to achieve further operating cost savings and other business synergies, including revenue growth, as a result of the acquisition which are not reflected in the pro forma amounts that follow. As a result, actual amounts would have differed from the unaudited pro forma information presented.
		Unaudited Pro Forma
		Three Months Ended March 31,
		2014
		(in thousands except per share)
	Total revenues (net interest income plus noninterest income)	$	97,488
	Net income	$	21,078
	Earnings per share - basic	$	0.38
	Earnings per share - diluted	$	0.37
	In connection with the Intermountain acquisition, Columbia recognized $2.9 million in acquisition-related expenses for the three month period ended March 31, 2015 and recognized no acquisition-related expenses for the three month period ended March 31, 2014. In addition, related to the acquisition of West Coast Bancorp (“West Coast”) which was completed on April 1, 2013, Columbia recognized $72 thousand and $966 thousand in acquisition-related expenses for the three month periods ended March 31, 2015 and 2014, respectively.
	The following table shows the impact of the acquisition-related expenses related to the acquisition of Intermountain for the three months ended March 31, 2015 to the various components of noninterest expense:
		Three Months Ended March 31,
		2015
		(in thousands)
	Noninterest Expense
	Compensation and employee benefits	$	273
	Occupancy	499
	Advertising and promotion	96
	Data processing and communications	1,558
	Legal and professional fees	385
	Other	91
	Total impact of acquisition-related costs to noninterest expense	$	2,902
	See Note 2, Business Combinations, in Item 8 of our 2014 Form 10-K for additional details related to the Intermountain acquisition.

Securities

Securities	3 Months Ended
	Mar. 31, 2015
Available-for-sale Securities [Abstract]
Securities	Securities
	The following table summarizes the amortized cost, gross unrealized gains and losses and the resulting fair value of securities available for sale:
		Amortized			Gross			Gross			Fair Value
		Cost			Unrealized			Unrealized
					Gains			Losses
		(in thousands)
	March 31, 2015
	U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	1,093,576		$	13,765		$	(4,641	)	$	1,102,700
	State and municipal securities	486,969			15,434			(732		)	501,671
	U.S. government agency and government-sponsored enterprise securities	375,230			2,551			(983		)	376,798
	U.S. government securities	20,918			—			(140		)	20,778
	Other securities	5,284			40			(112		)	5,212
	Total	$	1,981,977		$	31,790		$	(6,608	)	$	2,007,159
	December 31, 2014
	U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	1,160,378		$	10,219		$	(8,210	)	$	1,162,387
	State and municipal securities	483,578			14,432			(1,526		)	496,484
	U.S. government agency and government-sponsored enterprise securities	416,919			856			(4,069		)	413,706
	U.S. government securities	20,910			—			(411		)	20,499
	Other securities	5,284			20			(123		)	5,181
	Total	$	2,087,069		$	25,527		$	(14,339	)	$	2,098,257
	Proceeds from sales of securities available-for-sale were $57.2 million and $6.4 million for the three months ended March 31, 2015 and 2014, respectively. The following table provides the gross realized gains and losses on the sales of securities for the periods indicated:
		Three Months Ended
		March 31,
		2015			2014
		(in thousands)
	Gross realized gains	$	730		$	223
	Gross realized losses	(9		)	—
	Net realized gains	$	721		$	223
	The scheduled contractual maturities of investment securities available for sale at March 31, 2015 are presented as follows:
		March 31, 2015
		Amortized Cost			Fair Value
		(in thousands)
	Due within one year	$	15,480		$	15,601
	Due after one year through five years	404,752			406,989
	Due after five years through ten years	526,230			534,584
	Due after ten years	1,030,231			1,044,773
	Other securities with no stated maturity	5,284			5,212
	Total investment securities available-for-sale	$	1,981,977		$	2,007,159
	The following table summarizes the carrying value of securities pledged as collateral to secure public deposits, borrowings and other purposes as permitted or required by law:
		March 31, 2015
		(in thousands)
	Washington and Oregon State to secure public deposits	$	323,771
	Federal Reserve Bank to secure borrowings	36,945
	Other securities pledged	156,385
	Total securities pledged as collateral	$	517,101
	The following table shows the gross unrealized losses and fair value of the Company’s investments with unrealized losses that are not deemed to be other-than-temporarily impaired, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at March 31, 2015 and December 31, 2014:
		Less than 12 Months						12 Months or More						Total
		Fair			Unrealized			Fair			Unrealized			Fair		Unrealized
		Value			Losses			Value			Losses			Value		Losses
		(in thousands)
	March 31, 2015
	U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	94,304		$	(634	)	$	213,050		$	(4,007	)	$	307,354	$	(4,641	)
	State and municipal securities	45,809			(227		)	31,597			(505		)	77,406		(732		)
	U.S. government agency and government-sponsored enterprise securities	999			(1		)	178,013			(982		)	179,012		(983		)
	U.S. government securities	1,050			(1		)	19,728			(139		)	20,778		(140		)
	Other securities	—			—			2,843			(112		)	2,843		(112		)
	Total	$	142,162		$	(863	)	$	445,231		$	(5,745	)	$	587,393	$	(6,608	)
	December 31, 2014
	U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	258,825		$	(1,287	)	$	279,015		$	(6,924	)	$	537,840	$	(8,211	)
	State and municipal securities	71,026			(543		)	44,148			(982		)	115,174		(1,525		)
	U.S. government agency and government-sponsored enterprise securities	105,250			(518		)	216,221			(3,551		)	321,471		(4,069		)
	U.S. government securities	—			—			19,450			(411		)	19,450		(411		)
	Other securities	2,313			(2		)	2,834			(121		)	5,147		(123		)
	Total	$	437,414		$	(2,350	)	$	561,668		$	(11,989	)	$	999,082	$	(14,339	)
At March 31, 2015, there were 77 U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations securities in an unrealized loss position, of which 34 were in a continuous loss position for 12 months or more. The decline in fair value is attributable to changes in interest rates relative to where these investments fall within the yield curve and their individual characteristics. Because the Company does not intend to sell these securities nor does the Company consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be upon maturity, the Company does not consider these investments to be other-than-temporarily impaired at March 31, 2015.
At March 31, 2015, there were 66 state and municipal government securities in an unrealized loss position, of which 32 were in a continuous loss position for 12 months or more. The unrealized losses on state and municipal securities were caused by interest rate changes or widening of market spreads subsequent to the purchase of the individual securities. Management monitors published credit ratings of these securities for adverse changes. As of March 31, 2015, none of the rated obligations of state and local government entities held by the Company had a below investment grade credit rating. Because the credit quality of these securities are investment grade and the Company does not intend to sell these securities nor does the Company consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be upon maturity, the Company does not consider these investments to be other-than-temporarily impaired at March 31, 2015.
At March 31, 2015, there were 18 U.S. government agency and government-sponsored enterprise securities in an unrealized loss position, 14 of which were in a continuous loss position for 12 months or more. The decline in fair value is attributable to changes in interest rates relative to where these investments fall within the yield curve and their individual characteristics. Because the Company does not currently intend to sell these securities nor does the Company consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be upon maturity, the Company does not consider these investments to be other-than-temporarily impaired at March 31, 2015.
At March 31, 2015, there were four U.S. government securities in an unrealized loss position, two of which were in a continuous loss position for 12 months or more. The decline in fair value is attributable to changes in interest rates relative to where these investments fall within the yield curve and their individual characteristics. Because the Company does not currently intend to sell these securities nor does the Company consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be upon maturity, the Company does not consider these investments to be other-than-temporarily impaired at March 31, 2015.
At March 31, 2015, there was one other security in an unrealized loss position, which was in a continuous unrealized loss position for 12 months or more. The decline in fair value is attributable to changes in interest rates and the additional risk premium investors are demanding for investment securities with these characteristics. The Company does not consider this investment to be other-than-temporarily impaired at March 31, 2015 as it has the intent and ability to hold the investment for sufficient time to allow for recovery in the market value.

Loans

Loans	3 Months Ended
	Mar. 31, 2015
Loans Receivable, Net [Abstract]
Loans	Loans
	The Company’s loan portfolio includes originated and purchased loans. Originated loans and purchased 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 are referred to collectively as loans, excluding purchased credit impaired loans. Purchased loans for which there was, at 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.”
	The following is an analysis of the loan portfolio by major types of loans (net of unearned income):
		March 31, 2015											December 31, 2014
		Loans, excluding PCI loans				PCI Loans				Total			Loans, excluding PCI loans			PCI Loans			Total
		(in thousands)
	Commercial business	$	2,139,873			$	46,335			$	2,186,208		$	2,119,565		$	44,505		$	2,164,070
	Real estate:
	One-to-four family residential	173,739				26,601				200,340			175,571			26,993			202,564
	Commercial and multifamily residential	2,374,454				118,230				2,492,684			2,363,541			128,769			2,492,310
	Total real estate	2,548,193				144,831				2,693,024			2,539,112			155,762			2,694,874
	Real estate construction:
	One-to-four family residential	124,017				3,797				127,814			116,866			4,021			120,887
	Commercial and multifamily residential	119,880				2,238				122,118			134,443			2,321			136,764
	Total real estate construction	243,897				6,035				249,932			251,309			6,342			257,651
	Consumer	352,960				22,638				375,598			364,182			23,975			388,157
	Less: Net unearned income	(53,867		)		—				(53,867		)	(59,374		)	—			(59,374		)
	Total loans, net of unearned income	5,231,056				219,839				5,450,895			5,214,794			230,584			5,445,378
	Less: Allowance for loan and lease losses	(53,703		)		(16,531		)		(70,234		)	(53,233		)	(16,336		)	(69,569		)
	Total loans, net	$	5,177,353			$	203,308			$	5,380,661		$	5,161,561		$	214,248		$	5,375,809
	Loans held for sale	$	3,545			$	—			$	3,545		$	1,116		$	—		$	1,116
	At March 31, 2015 and December 31, 2014, the Company had no material foreign activities. Substantially all of the Company’s loans and unfunded commitments are geographically concentrated in its service areas within the states of Washington, Oregon and Idaho.
	The Company has made loans to executive officers and directors of the Company and related interests. These loans are made on the same terms, including interest rates and collateral, as those prevailing at the time for comparable transactions with unrelated persons and do not involve more than the normal risk of collectability. The aggregate dollar amount of these loans was $12.7 million at March 31, 2015 and $13.2 million at December 31, 2014. During the first three months of 2015, there were no advances and repayments totaled $430 thousand.
	At March 31, 2015 and December 31, 2014, $1.30 billion and $1.08 billion of commercial and residential real estate loans were pledged as collateral on Federal Home Loan Bank of Seattle (“FHLB”) borrowings and additional borrowing capacity. The Company has also pledged $47.0 million and $46.0 million of commercial loans to the Federal Reserve Bank for additional borrowing capacity at March 31, 2015 and December 31, 2014, respectively.
	The following is an analysis of nonaccrual loans as of March 31, 2015 and December 31, 2014:
		March 31, 2015								December 31, 2014
		Recorded				Unpaid Principal				Recorded			Unpaid Principal
		Investment				Balance				Investment			Balance
		Nonaccrual				Nonaccrual				Nonaccrual			Nonaccrual
		Loans				Loans				Loans			Loans
		(in thousands)
	Commercial business:
	Secured	$	17,240			$	20,573			$	16,552		$	21,453
	Unsecured	189				211				247			269
	Real estate:
	One-to-four family residential	4,429				6,109				2,822			5,680
	Commercial & multifamily residential:
	Commercial land	1,616				1,560				821			1,113
	Income property	887				887				3,200			5,521
	Owner occupied	1,995				2,036				3,826			5,837
	Real estate construction:
	One-to-four family residential:
	Land and acquisition	871				871				95			112
	Residential construction	1,263				1,263				370			370
	Commercial & multifamily residential:
	Owner occupied	470				489				480			489
	Consumer	2,868				3,799				2,939			3,930
	Total	$	31,828			$	37,798			$	31,352		$	44,774
	Loans, excluding purchased credit impaired loans
	The following is an aging of the recorded investment of the loan portfolio as of March 31, 2015 and December 31, 2014:
		Current				30 - 59				60 - 89			Greater			Total			Nonaccrual			Total Loans
		Loans				Days				Days			than 90			Past Due			Loans
						Past Due				Past Due			Days Past
													Due
	March 31, 2015	(in thousands)
	Commercial business:
	Secured	$	2,024,277			$	11,910			$	1,874		$	58		$	13,842		$	17,240		$	2,055,359
	Unsecured	78,351				492				120			67			679			189			79,219
	Real estate:
	One-to-four family residential	164,962				771				124			21			916			4,429			170,307
	Commercial & multifamily residential:
	Commercial land	186,904				4,303				355			264			4,922			1,616			193,442
	Income property	1,305,595				2,502				560			—			3,062			887			1,309,544
	Owner occupied	841,551				2,206				435			—			2,641			1,995			846,187
Real estate construction:
One-to-four family residential:
Land and acquisition	15,860				67				—			—			67			871			16,798
Residential construction	104,378				—				—			4			4			1,263			105,645
Commercial & multifamily residential:
Income property	62,958				—				—			—			—			—			62,958
Owner occupied	54,969				—				—			—			—			470			55,439
Consumer	331,566				1,509				193			22			1,724			2,868			336,158
Total	$	5,171,371			$	23,760			$	3,661		$	436		$	27,857		$	31,828		$	5,231,056
	Current				30 - 59				60 - 89			Greater			Total			Nonaccrual			Total Loans
	Loans				Days				Days			than 90			Past Due			Loans
					Past Due				Past Due			Days Past
												Due
December 31, 2014	(in thousands)
Commercial business:
Secured	$	2,004,418			$	5,137			$	6,149		$	1,372		$	12,658		$	16,552		$	2,033,628
Unsecured	79,661				185				—			—			185			247			80,093
Real estate:
One-to-four family residential	167,197				1,700				45			—			1,745			2,822			171,764
Commercial & multifamily residential:
Commercial land	187,470				1,454				34			—			1,488			821			189,779
Income property	1,294,982				3,031				786			—			3,817			3,200			1,301,999
Owner occupied	839,689				937				289			—			1,226			3,826			844,741
Real estate construction:
One-to-four family residential:
Land and acquisition	15,462				953				—			—			953			95			16,510
Residential construction	97,821				326				—			4			330			370			98,521
Commercial & multifamily residential:
Income property	73,783				—				—			—			—			—			73,783
Owner occupied	57,470				—				994			—			994			480			58,944
Consumer	341,032				933				118			10			1,061			2,939			345,032
Total	$	5,158,985			$	14,656			$	8,415		$	1,386		$	24,457		$	31,352		$	5,214,794
The following is an analysis of impaired loans as of March 31, 2015 and December 31, 2014:
	Recorded Investment				Recorded Investment				Impaired Loans With									Impaired Loans Without
	of Loans				of Loans				Recorded Allowance									Recorded Allowance
	Collectively Measured				Individually
	for Contingency				Measured for
	Provision				Specific
					Impairment				Recorded			Unpaid			Related			Recorded			Unpaid
									Investment			Principal			Allowance			Investment			Principal
												Balance									Balance
March 31, 2015	(in thousands)
Commercial business:
Secured	$	2,044,486			$	10,873			$	96		$	96		$	24		$	10,777		$	12,986
Unsecured	79,219				—				—			—			—			—			—
Real estate:
One-to-four family residential	166,129				4,178				420			461			115			3,758			4,220
Commercial & multifamily residential:
Commercial land	192,972				470				—			—			—			470			470
Income property	1,307,556				1,988				—			—			—			1,988			2,355
Owner occupied	839,157				7,030				578			578			24			6,452			8,944
Real estate construction:
One-to-four family residential:
Land and acquisition	15,818				980				109			108			67			871			871
Residential construction	104,752				893				—			—			—			893			893
Commercial & multifamily residential:
Income property	62,958				—				—			—			—			—			—
Owner occupied	55,439				—				—			—			—			—			—
Consumer	335,474				684				—			—			—			684			895
Total	$	5,203,960			$	27,096			$	1,203		$	1,243		$	230		$	25,893		$	31,634
	Recorded Investment				Recorded Investment				Impaired Loans With									Impaired Loans Without
	of Loans				of Loans				Recorded Allowance									Recorded Allowance
	Collectively Measured				Individually
	for Contingency				Measured for
	Provision				Specific
					Impairment				Recorded			Unpaid			Related			Recorded			Unpaid
									Investment			Principal			Allowance			Investment			Principal
												Balance									Balance
December 31, 2014	(in thousands)
Commercial business:
Secured	$	2,023,104			$	10,524			$	99		$	99		$	25		$	10,425		$	12,410
Unsecured	80,091				2				2			2			2			—			—
Real estate:
One-to-four family residential	169,619				2,145				424			465			120			1,721			2,370
Commercial & multifamily residential:
Commercial land	189,779				—				—			—			—			—			—
Income property	1,295,650				6,349				—			—			—			6,349			10,720
Owner occupied	835,895				8,846				582			582			27			8,264			12,732
Real estate construction:
One-to-four family residential:
Land and acquisition	16,401				109				109			109			67			—			—
Residential construction	98,521				—				—			—			—			—			—
Commercial & multifamily residential:
Income property	73,783				—				—			—			—			—			—
Owner occupied	58,944				—				—			—			—			—			—
Consumer	344,908				124				—			—			—			124			201
Total	$	5,186,695			$	28,099			$	1,216		$	1,257		$	241		$	26,883		$	38,433
The following table provides additional information on impaired loans for the three month periods indicated:
	Three Months Ended March 31,
	2015								2014
	Average Recorded				Interest Recognized				Average Recorded			Interest Recognized
	Investment				on				Investment			on
	Impaired Loans				Impaired Loans				Impaired Loans			Impaired Loans
	(in thousands)
Commercial business:
Secured	$	10,698			$	7			$	6,232		$	17
Unsecured	1				—				31			—
Real estate:
One-to-four family residential	3,162				13				1,856			13
Commercial & multifamily residential:
Commercial land	235				—				111			—
Income property	4,168				10				6,436			62
Owner occupied	7,938				234				10,140			241
Real estate construction:
One-to-four family residential:
Land and acquisition	544				1				1,569			1
Residential construction	446				—				—			—
Consumer	404				2				163			2
Total	$	27,596			$	267			$	26,538		$	336
There were no troubled debt restructurings (“TDR”) during the three months ended March 31, 2015. The following is an analysis of loans classified as TDR during the three months ended March 31, 2014:
	Three months ended March 31, 2014
	Number of TDR Modifications			Pre-Modification				Post-Modification
				Outstanding				Outstanding
				Recorded				Recorded
				Investment				Investment
	(dollars in thousands)
Commercial business:
Secured	2			$	546			$	546
Real estate:
One-to-four family residential	2			494				494
Commercial and multifamily residential:
Income property	1			143				126
Total	5			$	1,183			$	1,166
The Company’s loans classified as TDR are loans that have been modified or the borrower has been granted special concessions due to financial difficulties that, if not for the challenges of the borrower, the Company would not otherwise consider. The TDR modifications or concessions are made to increase the likelihood that these borrowers with financial difficulties will be able to satisfy their debt obligations as amended. The concessions granted in the restructurings completed in the three month period ending March 31, 2014 largely consisted of maturity extensions, interest rate modifications or a combination of both. In limited circumstances, a reduction in the principal balance of the loan could also be made as a concession. Credit losses for loans classified as TDR are measured on the same basis as impaired loans. For impaired loans, an allowance is established when the collateral value less selling costs (or discounted cash flows or observable market price) of the impaired loan is lower than the recorded investment of that loan.
The Company had no commitments to lend additional funds on loans classified as TDR as of March 31, 2015 and December 31, 2014. The Company did not have any loans modified as TDR that defaulted within twelve months of being modified as TDR during the three month periods ended March 31, 2015 and 2014.
Purchased Credit Impaired Loans (“PCI Loans”)
PCI loans are accounted for under ASC 310-30 and initially measured at fair value based on expected future cash flows over the life of the loans. Loans that have common risk characteristics are aggregated into pools. The Company remeasures contractual and expected cash flows, at the pool-level, on a quarterly basis.
Contractual cash flows are calculated based upon the loan pool terms after applying a prepayment factor. Calculation of the applied prepayment factor for contractual cash flows is the same as described below for expected cash flows.
Inputs to the determination of expected cash flows include cumulative default and prepayment data as well as loss severity and recovery lag information. Cumulative default and prepayment data are calculated via a transition matrix. The transition matrix is a matrix of probability values that specifies the probability of a loan pool transitioning into a particular delinquency state (e.g. 0-30 days past due, 31 to 60 days, etc.) given its delinquency state at the remeasurement date. Loss severity factors are based upon either actual charge-off data within the loan pools or industry averages and recovery lags are based upon the collateral within the loan pools.
The excess of cash flows expected to be collected over the initial fair value of purchased credit impaired loans is referred to as the accretable yield and is accreted into interest income over the estimated life of the acquired loans using the effective yield method. Other adjustments to the accretable yield include changes in the estimated remaining life of the acquired loans, changes in expected cash flows and changes of indices for acquired loans with variable interest rates.
The following is an analysis of our PCI loans, net of related allowance for losses and remaining valuation discounts as of March 31, 2015 and December 31, 2014:
	March 31, 2015				December 31, 2014
	(in thousands)
Commercial business	$	52,115			$	50,334
Real estate:
One-to-four family residential	31,127				31,981
Commercial and multifamily residential	127,952				140,398
Total real estate	159,079				172,379
Real estate construction:
One-to-four family residential	4,026				4,353
Commercial and multifamily residential	2,501				2,588
Total real estate construction	6,527				6,941
Consumer	25,390				26,814
Subtotal of PCI loans	243,111				256,468
Less:
Valuation discount resulting from acquisition accounting	23,272				25,884
Allowance for loan losses	16,531				16,336
PCI loans, net of allowance for loan losses	$	203,308			$	214,248
The following table shows the changes in accretable yield for PCI loans for the three months ended March 31, 2015 and 2014:
	Three Months Ended March 31,
	2015				2014
	(in thousands)
Balance at beginning of period	$	73,849			$	103,907
Accretion	(6,319		)		(10,569		)
Disposals	(1,093		)		(2,826		)
Reclassifications from nonaccretable difference	2,289				11,031
Balance at end of period	$	68,726			$	101,543

Allowance_for_Loan_and_Lease_L

Allowance for Loan and Lease Losses and Unfunded Commitments and Letters of Credit	3 Months Ended
	Mar. 31, 2015
Allowance For Loan And Lease Losses And Unfunded Loan Commitments And Letters Of Credit
Allowance For Loan And Lease Losses And Unfunded Loan Commitments And Letters Of Credit Text Block
		Allowance for Loan and Lease Losses and Unfunded Commitments and Letters of Credit
	Loans, excluding PCI loans
	We maintain an allowance for loan and lease losses (“ALLL”) to absorb losses inherent in the loan portfolio. The size of the ALLL is determined through quarterly assessments of the probable estimated losses in the loan portfolio. Our methodology for making such assessments and determining the adequacy of the ALLL includes the following key elements:
	1	General valuation allowance consistent with the Contingencies topic of the FASB ASC.
	2	Classified loss reserves on specific relationships. Specific allowances for identified problem loans are determined in accordance with the Receivables topic of the FASB ASC.
	3	The unallocated allowance provides for other factors inherent in our loan portfolio that may not have been contemplated in the general and specific components of the allowance. This unallocated amount generally comprises less than 5% of the allowance. The unallocated amount is reviewed quarterly based on trends in credit losses, the results of credit reviews and overall economic trends.
	The general valuation allowance is calculated quarterly using quantitative and qualitative information about specific loan classes. The minimum required level with respect to which an entity develops a methodology to determine its ALLL is by general categories of loans, such as commercial business, real estate, and consumer. However, the Company’s methodology in determining its ALLL is prepared in a more detailed manner at the loan class level, utilizing specific categories such as commercial business secured, commercial business unsecured, real estate commercial land, and real estate income property multifamily. The quantitative information uses historical losses from a specific loan class and incorporates the loan’s risk rating migration from origination to the point of loss based upon the consideration of an appropriate look back period.
	A loan’s risk rating is primarily determined based upon the borrower’s ability to fulfill its debt obligation from a cash flow perspective. In the event there is financial deterioration of the borrower, the borrower’s other sources of income or repayment are also considered, including recent appraisal values for collateral dependent loans. The qualitative information takes into account general economic and business conditions affecting our marketplace, seasoning of the loan portfolio, duration of the business cycle, etc. to ensure our methodologies reflect the current economic environment and other factors as using historical loss information exclusively may not give an accurate estimate of inherent losses within the Company’s loan portfolio.
	When a loan is deemed to be impaired, the Company has to determine if a specific valuation allowance is required for that loan. The specific valuation allowance is a reserve, calculated at the individual loan level, for each loan determined to be both, impaired and containing a value less than its recorded investment. The Company measures the impairment based on the discounted expected future cash flows, observable market price, or the fair value of the collateral less selling costs if the loan is collateral dependent or if foreclosure is probable. The specific reserve for each loan is equal to the difference between the recorded investment in the loan and its determined impairment value.
	The ALLL is increased by provisions for loan and lease losses (“provision”) charged to expense, and is reduced by loans charged off, net of recoveries or a recovery of previous provisions. While the Company’s management believes the best information available is used to determine the ALLL, changes in market conditions could result in adjustments to the ALLL, affecting net income, if circumstances differ from the assumptions used in determining the ALLL.
	We have used the same methodology for ALLL calculations during the three months ended March 31, 2015 and 2014. Adjustments to the percentages of the ALLL allocated to loan categories are made based on trends with respect to delinquencies and problem loans within each class of loans. The Company reviews the ALLL quantitative and qualitative methodology on a quarterly basis and makes adjustments when appropriate. The Company continues to strive towards maintaining a conservative approach to credit quality and will continue to make revisions to our ALLL as necessary to maintain adequate reserves. The Company carefully monitors the loan portfolio and continues to emphasize the importance of credit quality.
	Once it is determined that all or a portion of a loan balance is uncollectable, and the amount can be reasonably estimated, the uncollectable portion of the loan is charged-off.
	PCI Loans
	Purchased credit impaired loans that have common risk characteristics are aggregated into loan pools. When required, we record impairment, at the pool-level, to adjust the pool’s carrying value to its net present value of expected future cash flows. Quarterly, we re-measure expected loan pool cash flows. If, due to credit deterioration, the present value of expected cash flows is less than carrying value, we reduce the loan pool’s carrying value by adjusting the ALLL with an impairment charge to earnings which is recorded as provision for loan losses. If credit quality improves and the present value of expected cash flows exceeds carrying value, we increase the loan pool’s carrying value by recapturing previously recorded ALLL, if any. See Note 5, Loans, for further discussion of the accounting for PCI loans.
	Credit losses attributable to draws on purchased credit impaired loans, advanced subsequent to the loan purchase date, are accounted for under ASC 450-20 and those amounts are also subject to the Company’s internal and external credit review. An ALLL is estimated in a similar manner as loans, excluding PCI loans, and a provision for loan losses is charged to earnings as necessary.
	The following tables show a detailed analysis of the ALLL for the three months ended March 31, 2015 and 2014:
			Beginning		Charge-offs			Recoveries		Provision (Recovery)			Ending		Specific		General
			Balance										Balance		Reserve		Allocation
	Three months ended March 31, 2015		(in thousands)
	Commercial business:
	Secured		$	25,923	$	(1,386	)	$	512	$	712		$	25,761	$	24	$	25,737
	Unsecured		927		(40		)	106		19			1,012		—		1,012
	Real estate:
	One-to-four family residential		2,281		(8		)	12		(921		)	1,364		115		1,249
	Commercial & multifamily residential:
	Commercial land		799		—			—		28			827		—		827
	Income property		9,159		—			3,252		(3,971		)	8,440		—		8,440
	Owner occupied		5,007		—			9		596			5,612		24		5,588
	Real estate construction:
	One-to-four family residential:
	Land and acquisition		1,197		—			2		(173		)	1,026		67		959
	Residential construction		1,860		—			26		(96		)	1,790		—		1,790
	Commercial & multifamily residential:
	Income property		622		—			3		202			827		—		827
	Owner occupied		434		—			—		65			499		—		499
	Consumer		3,180		(891		)	273		273			2,835		—		2,835
	Purchased credit impaired		16,336		(4,100		)	1,686		2,609			16,531		—		16,531
	Unallocated		1,844		—			—		1,866			3,710		—		3,710
	Total		$	69,569	$	(6,425	)	$	5,881	$	1,209		$	70,234	$	230	$	70,004
			Beginning		Charge-offs			Recoveries		Provision (Recovery)			Ending		Specific		General
			Balance										Balance		Reserve		Allocation
	Three months ended March 31, 2014		(in thousands)
	Commercial business:
	Secured		$	31,027	$	(198	)	$	448	$	(2,476	)	$	28,801	$	1,521	$	27,280
	Unsecured		696		(35		)	42		43			746		27		719
	Real estate:
	One-to-four family residential		1,252		(207		)	28		121			1,194		133		1,061
	Commercial & multifamily residential:
	Commercial land		489		—			17		73			579		—		579
	Income property		9,234		—			13		860			10,107		—		10,107
	Owner occupied		3,605		(1,023		)	9		1,969			4,560		38		4,522
	Real estate construction:
	One-to-four family residential:
	Land and acquisition		610		—			39		(69		)	580		71		509
	Residential construction		822		—			3		(129		)	696		—		696
	Commercial & multifamily residential:
	Income property		285		—			—		35			320		—		320
	Owner occupied		58		—			—		96			154		—		154
	Consumer		2,547		(727		)	253		564			2,637		3		2,634
	Purchased credit impaired		20,174		(4,273		)	1,806		2,422			20,129		—		20,129
	Unallocated		1,655		—			—		(1,587		)	68		—		68
	Total		$	72,454	$	(6,463	)	$	2,658	$	1,922		$	70,571	$	1,793	$	68,778
	Changes in the allowance for unfunded commitments and letters of credit, a component of other liabilities in the consolidated balance sheet, are summarized as follows:
		Three Months Ended
		March 31,
		2015		2014
		(in thousands)
Balance at beginning of period		$	2,655	$	2,505
Net changes in the allowance for unfunded commitments and letters of credit		—		(50		)
Balance at end of period		$	2,655	$	2,455
Risk Elements
The extension of credit in the form of loans or other credit products to individuals and businesses is one of our principal business activities. Our policies and applicable laws and regulations require risk analysis as well as ongoing portfolio and credit management. We manage our credit risk through lending limit constraints, credit review, approval policies and extensive, ongoing internal monitoring. We also manage credit risk through diversification of the loan portfolio by type of loan, type of industry and type of borrower and by limiting the aggregation of debt to a single borrower.
Risk ratings are reviewed and updated whenever appropriate, with more periodic reviews as the risk and dollar value of loss on the loan increases. In the event full collection of principal and interest is not reasonably assured, the loan is appropriately downgraded and, if warranted, placed on nonaccrual status even though the loan may be current as to principal and interest payments. Additionally, we assess whether an impairment of a loan warrants specific reserves or a write-down of the loan.
Pass loans are generally considered to have sufficient sources of repayment in order to repay the loan in full in accordance with all terms and conditions. Special mention loans have potential weaknesses that, if left uncorrected, may result in deterioration of the repayment prospects for the asset or in the Company’s credit position at some future date. Loans with a risk rating of Substandard or worse are reported as classified loans in our ALLL analysis. We review these loans to assess the ability of our borrowers to service all interest and principal obligations and, as a result, the risk rating may be adjusted accordingly. Substandard loans reflect loans where a loss is possible if loan weaknesses are not corrected. Doubtful loans have a high probability of loss, however, the amount of loss has not yet been determined. Loss loans are considered uncollectable and when identified, are charged off.
The following is an analysis of the credit quality of our loan portfolio, excluding PCI loans, as of March 31, 2015 and December 31, 2014:
		Pass		Special Mention			Substandard		Doubtful			Loss		Total
March 31, 2015		(in thousands)
Loans, excluding PCI loans:
Commercial business:
Secured		$	1,995,680	$	19,210		$	40,469	$	—		$	—	$	2,055,359
Unsecured		78,498		—			721		—			—		79,219
Real estate:
One-to-four family residential		162,448		1,465			6,394		—			—		170,307
Commercial and multifamily residential:
Commercial land		187,519		3,459			2,464		—			—		193,442
Income property		1,301,779		3,517			4,248		—			—		1,309,544
Owner occupied		828,244		1,757			16,186		—			—		846,187
Real estate construction:
One-to-four family residential:
Land and acquisition		16,180		166			452		—			—		16,798
Residential construction		103,257		680			1,708		—			—		105,645
Commercial and multifamily residential:
Income property		62,958		—			—		—			—		62,958
Owner occupied		54,563		—			876		—			—		55,439
Consumer		331,413		—			4,745		—			—		336,158
Total		$	5,122,539	$	30,254		$	78,263	$	—		$	—	5,231,056
Less:
Allowance for loan and lease losses														53,703
Loans, excluding PCI loans, net														$	5,177,353
		Pass		Special Mention			Substandard		Doubtful			Loss		Total
December 31, 2014		(in thousands)
Loans, excluding PCI loans:
Commercial business:
Secured		$	1,963,210	$	15,790		$	54,628	$	—		$	—	$	2,033,628
Unsecured		79,534		—			559		—			—		80,093
Real estate:
One-to-four family residential		163,914		55			7,795		—			—		171,764
Commercial and multifamily residential:
Commercial land		183,701		4,217			1,861		—			—		189,779
Income property		1,287,729		5,885			8,385		—			—		1,301,999
Owner occupied		825,694		7,876			11,171		—			—		844,741
Real estate construction:
One-to-four family residential:
Land and acquisition		15,307		167			1,036		—			—		16,510
Residential construction		96,031		909			1,581		—			—		98,521
Commercial and multifamily residential:
Income property		73,783		—			—		—			—		73,783
Owner occupied		58,055		—			889		—			—		58,944
Consumer		339,695		68			5,269		—			—		345,032
Total		$	5,086,653	$	34,967		$	93,174	$	—		$	—	5,214,794
Less:
Allowance for loan and lease losses														53,233
Loans, excluding PCI loans, net														$	5,161,561
The following is an analysis of the credit quality of our PCI loan portfolio as of March 31, 2015 and December 31, 2014:
		Pass		Special Mention			Substandard		Doubtful			Loss		Total
March 31, 2015		(in thousands)
PCI loans:
Commercial business:
Secured		$	39,919	$	1,040		$	9,060	$	—		$	—	$	50,019
Unsecured		2,057		—			39		—			—		2,096
Real estate:
One-to-four family residential		27,881		—			3,246		—			—		31,127
Commercial and multifamily residential:
Commercial land		8,739		—			1,668		—			—		10,407
Income property		45,298		—			12,031		—			—		57,329
Owner occupied		56,004		336			3,876		—			—		60,216
Real estate construction:
One-to-four family residential:
Land and acquisition		1,452		—			894		—			—		2,346
Residential construction		732		—			948		—			—		1,680
Commercial and multifamily residential:
Income property		1,359		—			224		—			—		1,583
Owner occupied		918		—			—		—			—		918
Consumer		23,431		—			1,959		—			—		25,390
Total		$	207,790	$	1,376		$	33,945	$	—		$	—	243,111
Less:
Valuation discount resulting from acquisition accounting														23,272
Allowance for loan losses														16,531
PCI loans, net														$	203,308
		Pass		Special Mention			Substandard		Doubtful			Loss		Total
December 31, 2014		(in thousands)
PCI loans:
Commercial business:
Secured		$	37,927	$	937		$	9,223	$	—		$	—	$	48,087
Unsecured		2,156		—			91		—			—		2,247
Real estate:
One-to-four family residential		28,822		—			3,159		—			—		31,981
Commercial and multifamily residential:
Commercial land		9,104		—			6,240		—			—		15,344
Income property		51,435		1,892			7,186		—			—		60,513
Owner occupied		58,629		346			5,566		—			—		64,541
Real estate construction:
One-to-four family residential:
Land and acquisition		1,595		—			913		—			—		2,508
Residential construction		741		—			1,104		—			—		1,845
Commercial and multifamily residential:
Income property		1,435		—			227		—			—		1,662
Owner occupied		926		—			—		—			—		926
Consumer		24,037		—			2,777		—			—		26,814
Total		$	216,807	$	3,175		$	36,486	$	—		$	—	256,468
Less:
Valuation discount resulting from acquisition accounting														25,884
Allowance for loan losses														16,336
PCI loans, net														$	214,248

Other_Real_Estate_Owned

Other Real Estate Owned	3 Months Ended
	Mar. 31, 2015
Other Real Estate, Foreclosed Assets, and Repossessed Assets [Abstract]
Other Real Estate Owned	Other Real Estate Owned (“OREO”)
	The following tables set forth activity in OREO for the three months ended March 31, 2015 and 2014:
		Three Months Ended March 31,
		2015			2014
		(in thousands)
	Balance, beginning of period	$	22,190		$	35,927
	Transfers in	4,692			5,751
	Valuation adjustments	(197		)	(1,580		)
	Proceeds from sale of OREO property	(5,122		)	(11,205		)
	Gain on sale of OREO, net	1,736			1,659
	Balance, end of period	$	23,299		$	30,552

Covered_Assets_and_FDIC_Losssh

Covered Assets and FDIC Loss-sharing Asset	3 Months Ended
	Mar. 31, 2015
Covered Assets And FDIC Loss Sharing Asset
Covered Assets and FDIC Loss sharing Asset	FDIC Loss-sharing Asset and Covered Assets
	We are a party to eight loss-sharing agreements with the FDIC relating to four FDIC-assisted acquisitions. Such agreements cover a substantial portion of losses incurred on acquired covered loans and OREO. The loss-sharing agreements relate to the acquisitions of (1) Columbia River Bank in January 2010, (2) American Marine Bank in January 2010, (3) Summit Bank in May 2011, and (4) First Heritage Bank in May 2011. Under the terms of the loss-sharing agreements, the FDIC will absorb 80% of losses and share in 80% of loss recoveries up to specified amounts. With respect to loss-sharing agreements for two acquisitions completed in 2010, after those specified amounts, the FDIC will absorb 95% of losses and share in 95% of loss recoveries. The loss-sharing provisions of the agreements for commercial and single-family mortgage loans are in effect for five and ten years, respectively and the loss recovery provisions are in effect for eight and ten years, respectively. The loss-sharing provisions for the Columbia River Bank and American Marine Bank non-single family covered assets were effective through the end of the current quarter. Accordingly, further activity will be limited to recoveries through the first quarter of 2020 for assets covered by these loss-sharing agreements.
	Ten years and forty-five days after the applicable acquisition dates, the Bank must pay to the FDIC a clawback in the event the losses from the acquisitions fail to reach stated levels. The amount of the clawback is determined by a formula specified in each individual loss-sharing agreement. As of March 31, 2015, the net present value of the Bank’s estimated clawback liability was $4.2 million, which was included in other liabilities on the consolidated balance sheets.
	At March 31, 2015, the FDIC loss-sharing asset was comprised of a $10.6 million FDIC indemnification asset and a $4.0 million FDIC receivable. The indemnification asset represents the cash flows the Company expects to collect from the FDIC under the loss-sharing agreements and the FDIC receivable represents amounts from the FDIC for which the Company has requested reimbursement but has not yet received reimbursement.
	For PCI loans, the Company remeasures contractual and expected cash flows on a quarterly basis. When the quarterly remeasurement process results in a decrease in expected cash flows due to an increase in expected credit losses, impairment is recorded. As a result of this impairment, for loans covered by loss-share agreements with respect to which the loss-sharing provisions are still effective, the indemnification asset is increased to reflect anticipated future cash to be received from the FDIC. Consistent with the loss-sharing agreements between the Company and the FDIC, the amount of the increase to the indemnification asset is measured as 80% of the resulting impairment.
	Alternatively, when the quarterly remeasurement results in an increase in expected future cash flows due to a decrease in expected credit losses, the nonaccretable difference decreases and the effective yield of the related loan portfolio is increased. As a result of the improved expected cash flows, for loans covered by loss-share agreements with respect to which the loss-sharing provisions are still effective, the indemnification asset would be reduced first by the amount of any impairment previously recorded and, second, by increased amortization over the remaining life of the related loss-sharing agreement.
	The following table shows a detailed analysis of the FDIC loss-sharing asset for the three months ended March 31, 2015 and 2014:
		Three Months Ended March 31,
		2015			2014
		(in thousands)
	Balance at beginning of period	$	15,174		$	39,846
	Adjustments not reflected in income:
	Cash payments to (from) the FDIC	(659		)	1,678
	FDIC reimbursable losses (recoveries), net	(21		)	132
	Adjustments reflected in income:
	Amortization, net	(2,294		)	(6,452		)
	Loan impairment	1,532			1,938
	Sale of other real estate	(420		)	(756		)
	Write-downs of other real estate	1,071			516
	Other	261			(65		)
	Balance at end of period	$	14,644		$	36,837
	The following table presents information about the composition of the FDIC loss-sharing asset, the clawback liability, and the non-single family and the single family covered assets as of the date indicated:
		March 31, 2015
		Columbia River Bank			American Marine Bank			Summit Bank		First Heritage Bank		Total
		(in thousands)
	FDIC loss-sharing asset	$	2,124		$	4,824		$	4,162	$	3,534	$	14,644
	Clawback liability	$	4,063		$	136		$	—	$	—	$	4,199
	Non-single family covered assets	$	107,135		$	16,914		$	13,856	$	22,763	$	160,668
	Single family covered assets	$	9,994		$	26,391		$	6,322	$	2,479	$	45,186
	Loss-sharing expiration dates:
	Non-single family	First Quarter 2015			First Quarter 2015			Second Quarter 2016		Second Quarter 2016
	Single family	First Quarter 2020			First Quarter 2020			Second Quarter 2021		Second Quarter 2021
	Loss recovery expiration dates:
	Non-single family	First Quarter 2018			First Quarter 2018			Second Quarter 2019		Second Quarter 2019
	Single family	First Quarter 2020			First Quarter 2020			Second Quarter 2021		Second Quarter 2021

Goodwill_and_Intangible_Assets

Goodwill and Intangible Assets	3 Months Ended
	Mar. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Other Intangible Assets
	In accordance with the Intangibles – Goodwill and Other topic of the FASB ASC, goodwill is not amortized but is reviewed for potential impairment at the reporting unit level. Management analyzes its goodwill for impairment on an annual basis on July 31 and between annual tests in certain circumstances such as material adverse changes in legal, business, regulatory and economic factors. An impairment loss is recorded to the extent that the carrying amount of goodwill exceeds its implied fair value.
	The core deposit intangible (“CDI”) is evaluated for impairment if events and circumstances indicate a possible impairment. The CDI is amortized on an accelerated basis over an estimated life of 10 years.
	The following table sets forth activity for goodwill and other intangible assets for the periods indicated:
		Three Months Ended March 31,
		2015			2014
		(in thousands)
	Goodwill
	Total goodwill (1)	$	382,537		$	343,952
	Other intangible assets, net
	Core deposit intangible:
	Gross core deposit intangible balance at beginning of period (1)	58,598			47,698
	Accumulated amortization at beginning of period	(29,058		)	(22,765		)
	Core deposit intangible, net at beginning of period	29,540			24,933
	CDI current period amortization	(1,817		)	(1,579		)
	Total core deposit intangible, net at end of period	27,723			23,354
	Intangible assets not subject to amortization	919			919
	Other intangible assets, net at end of period	28,642			24,273
	Total goodwill and other intangible assets at end of period	$	411,179		$	368,225
	__________
	(1) See Note 3, Business Combinations, for additional information regarding goodwill and intangible assets recorded related to the acquisition of Intermountain on November 1, 2014.
	The following table provides the estimated future amortization expense of core deposit intangibles for the remaining nine months ending December 31, 2015 and the succeeding four years:
		Amount
		(in thousands)
	Year ending December 31,
	2015	$	5,065
	2016	5,945
	2017	4,913
	2018	3,855
	2019	2,951

Derivatives_and_Balance_Sheet_

Derivatives and Balance Sheet Offsetting	3 Months Ended
	Mar. 31, 2015
General Discussion of Derivative Instruments and Hedging Activities [Abstract]
Derivatives and Hedging Activities	Derivatives and Balance Sheet Offsetting
	The Company periodically enters into certain commercial loan interest rate swap agreements in order to provide commercial loan customers the ability to convert from variable to fixed interest rates. Under these agreements, the Company enters into a variable-rate loan agreement with a customer in addition to a swap agreement. This swap agreement effectively converts the customer’s variable rate loan into a fixed rate. The Company then enters into a corresponding swap agreement with a third-party in order to offset its exposure on the variable and fixed components of the customer agreement. As the interest rate swap agreements with the customers and third parties are not designated as hedges under the Derivatives and Hedging topic of the FASB ASC, the instruments are marked to market in earnings. The notional amount of open interest rate swap agreements at March 31, 2015 and December 31, 2014 was $222.9 million and $215.6 million, respectively. During the current quarter, a mark-to-market loss of $5 thousand was recorded to other noninterest expense. There was no earnings impact for the three month period ending March 31, 2014.
	The following table presents the fair value of derivatives not designated as hedging instruments at March 31, 2015 and December 31, 2014:
		Asset Derivatives									Liability Derivatives
		March 31, 2015						December 31, 2014			March 31, 2015						December 31, 2014
		Balance Sheet		Fair Value				Balance Sheet	Fair Value		Balance Sheet		Fair Value				Balance Sheet	Fair Value
		Location						Location			Location						Location
		(in thousands)
	Interest rate contracts	Other assets		$	14,244			Other assets	$	11,800	Other liabilities		$	14,300			Other liabilities	$	11,851
	The Company is party to interest rate contracts and repurchase agreements that are subject to enforceable master netting arrangements or similar agreements. Under these agreements, the Company may have the right to net settle multiple contracts with the same counterparty. The following tables show the gross interest rate swap agreements and repurchase agreements in the consolidated balance sheets and the respective collateral received or pledged in the form of other financial instruments, which are generally marketable securities. The collateral amounts in these tables are limited to the outstanding balances of the related asset or liability. Therefore, instances of overcollateralization are not shown.
		Gross Amounts of Recognized Assets/Liabilities				Gross Amounts Offset in the Consolidated Balance Sheets			Net Amounts of Assets/Liabilities Presented in the Consolidated Balance Sheets		Gross Amounts Not Offset in the Consolidated Balance Sheets
											Collateral Posted				Net Amount
	March 31, 2015	(in thousands)
	Assets
	Interest rate contracts	$	14,244			$	—		$	14,244	$	—			$	14,244
	Liabilities
	Interest rate contracts	$	14,300			$	—		$	14,300	$	(14,300	)		$	—
	Repurchase agreements	$	96,852			$	—		$	96,852	$	(96,852	)		$	—
	December 31, 2014
	Assets
	Interest rate contracts	$	11,800			$	—		$	11,800	$	—			$	11,800
	Liabilities
	Interest rate contracts	$	11,851			$	—		$	11,851	$	(11,851	)		$	—
	Repurchase agreements	$	105,080			$	—		$	105,080	$	(105,080	)		$	—

Shareholders_Equity

Shareholders' Equity	3 Months Ended
	Mar. 31, 2015
Stockholders' Equity Note [Abstract]
Shareholders' Equity	Shareholders’ Equity
	Preferred Stock. In conjunction with the 2013 acquisition of West Coast, the Company issued 8,782 shares of mandatorily convertible cumulative participating preferred stock, Series B (“Series B Preferred Stock”). The Series B Preferred Stock is not subject to the operation of a sinking fund. The Series B Preferred Stock is not redeemable by the Company and is perpetual with no maturity. The holders of Series B Preferred Stock have no general voting rights. If the Company declares and pays a dividend to its common shareholders, it must declare and pay to its holders of Series B Preferred Stock, on the same date, a dividend in an amount per share of the Series B Preferred Stock that is intended to provide such holders dividends in the amount they would have received if shares of Series B Preferred Stock had been converted into common stock as of that date. The outstanding shares of Series B Preferred Stock are convertible into 102,363 shares of Company common stock.
	Dividends. On January 29, 2015, the Company declared a quarterly cash dividend of $0.16 per common share and common share equivalent for holders of preferred stock, and a special cash dividend of $0.14 per common share and common share equivalent for holders of preferred stock, both payable on February 25, 2015 to shareholders of record at the close of business on February 11, 2015.
	Subsequent to quarter end, on April 22, 2015, the Company declared a regular quarterly cash dividend of $0.18 per common share and common share equivalent for holders of preferred stock, and a special cash dividend of $0.16 per common share and common share equivalent for holders of preferred stock, both payable on May 20, 2015 to shareholders of record at the close of business on May 6, 2015.
	The payment of cash dividends is subject to federal regulatory requirements for capital levels and other restrictions. In addition, the cash dividends paid by Columbia Bank to the Company are subject to both federal and state regulatory requirements.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Income	3 Months Ended
	Mar. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Abstract]
Accumulated Other Comprehensive Income	Accumulated Other Comprehensive Income (Loss)
	The following table shows changes in accumulated other comprehensive income (loss) by component for the three month periods ended March 31, 2015 and 2014:
		Unrealized Gains and Losses on Available-for-Sale Securities (1)			Unrealized Gains and Losses on Pension Plan Liability (1)			Total (1)
	Three months ended March 31, 2015	(in thousands)
	Beginning balance	$	7,462		$	(1,841	)	$	5,621
	Other comprehensive income (loss) before reclassifications	9,376			(280		)	9,096
	Amounts reclassified from accumulated other comprehensive income (loss) (2)	(459		)	28			(431		)
	Net current-period other comprehensive income (loss)	8,917			(252		)	8,665
	Ending balance	$	16,379		$	(2,093	)	$	14,286
	Three months ended March 31, 2014
	Beginning balance	$	(10,108	)	$	(1,936	)	$	(12,044	)
	Other comprehensive income before reclassifications	7,119			—			7,119
	Amounts reclassified from accumulated other comprehensive income (2)	(142		)	24			(118		)
	Net current-period other comprehensive income	6,977			24			7,001
	Ending balance	$	(3,131	)	$	(1,912	)	$	(5,043	)
	__________
	(1) All amounts are net of tax. Amounts in parenthesis indicate debits.
	(2) See following table for details about these reclassifications.
	The following table shows details regarding the reclassifications from accumulated other comprehensive income (loss) for the three month periods ended March 31, 2015 and 2014:
		Amount Reclassified from Accumulated Other Comprehensive Income (Loss)
		Three Months Ended March 31,						Affected line Item in the Consolidated
		2015			2014			Statement of Income
		(in thousands)
	Unrealized gains and losses on available-for-sale securities
	Investment securities gains	$	721		$	223		Investment securities gains, net
		721			223			Total before tax
		(262		)	(81		)	Income tax provision
		$	459		$	142		Net of tax
	Amortization of pension plan liability
	Actuarial losses	$	(44	)	$	(37	)	Compensation and employee benefits
		(44		)	(37		)	Total before tax
		16			13			Income tax benefit
		$	(28	)	$	(24	)	Net of tax

Fair_Value_Accounting_and_Meas

Fair Value Accounting and Measurement	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Accounting and Measurement	Fair Value Accounting and Measurement
	The Fair Value Measurements and Disclosures topic of the FASB ASC defines fair value, establishes a consistent framework for measuring fair value and expands disclosure requirements about fair value. We hold fixed and variable rate interest-bearing securities, investments in marketable equity securities and certain other financial instruments, which are carried at fair value. Fair value is determined based upon quoted prices when available or through the use of alternative approaches, such as matrix or model pricing, when market quotes are not readily accessible or available.
	The valuation techniques are based upon observable and unobservable inputs. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect our own market assumptions. These two types of inputs create the following fair value hierarchy:
	Level 1 – Quoted prices for identical instruments in active markets that are accessible at the measurement date.
	Level 2 – Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model derived valuations whose inputs are observable or whose significant value drivers are observable.
	Level 3 – Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable.
	Fair values are determined as follows:
	Securities at fair value are priced using a combination of market activity, industry recognized information sources, yield curves, discounted cash flow models and other factors. These fair value calculations are considered a Level 2 input method under the provisions of the Fair Value Measurements and Disclosures topic of the FASB ASC for all securities other than U.S. Treasury notes, which are considered a Level 1 input method.
	Interest rate contract positions are valued in models, which use as their basis, readily observable market parameters and are classified within Level 2 of the valuation hierarchy.
	The following table sets forth the Company’s financial assets and liabilities that were accounted for at fair value on a recurring basis at March 31, 2015 and December 31, 2014 by level within the fair value hierarchy. Financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement:
		Fair value		Fair Value Measurements at Reporting Date Using
				Level 1			Level 2		Level 3
	March 31, 2015	(in thousands)
	Assets
	Securities available for sale:
	U.S. government agency and government-sponsored enterprise mortgage-back securities and collateralized mortgage obligations	$	1,102,700	$	—		$	1,102,700	$	—
	State and municipal debt securities	501,671		—			501,671		—
	U.S. government agency and government-sponsored enterprise securities	376,798		—			376,798		—
	U.S. government securities	20,778		20,778			—		—
	Other securities	5,212		—			5,212		—
	Total securities available for sale	$	2,007,159	$	20,778		$	1,986,381	$	—
	Other assets (Interest rate contracts)	$	14,244	$	—		$	14,244	$	—
	Liabilities
	Other liabilities (Interest rate contracts)	$	14,300	$	—		$	14,300	$	—
		Fair value		Fair Value Measurements at Reporting Date Using
				Level 1			Level 2		Level 3
	December 31, 2014	(in thousands)
	Assets
	Securities available for sale:
	U.S. government agency and government-sponsored enterprise mortgage-back securities and collateralized mortgage obligations	$	1,162,387	$	—		$	1,162,387	$	—
	State and municipal debt securities	496,484		—			496,484		—
	U.S. government agency and government-sponsored enterprise securities	413,706		—			413,706		—
	U.S. government securities	20,499		20,499			—		—
	Other securities	5,181		—			5,181		—
	Total securities available for sale	$	2,098,257	$	20,499		$	2,077,758	$	—
	Other assets (Interest rate contracts)	$	11,800	$	—		$	11,800	$	—
	Liabilities
	Other liabilities (Interest rate contracts)	$	11,851	$	—		$	11,851	$	—
	There were no transfers between Level 1 and Level 2 of the valuation hierarchy during the three month periods ended March 31, 2015 and 2014. The Company recognizes transfers between levels of the valuation hierarchy based on the valuation level at the end of the reporting period.
	Nonrecurring Measurements
	Certain assets and liabilities are measured at fair value on a nonrecurring basis after initial recognition such as loans measured for impairment and OREO. The following methods were used to estimate the fair value of each such class of financial instrument:
	Impaired loans—A loan is considered to be impaired when, based on current information and events, it is probable that the Company will be unable to collect all amounts due (both interest and principal) according to the contractual terms of the loan agreement. Impaired loans are measured based on the present value of expected future cash flows discounted at the loan’s effective interest rate, a loan’s observable market price, or the fair market value of the collateral less estimated costs to sell if the loan is a collateral-dependent loan. Generally, the Company utilizes the fair market value of the collateral to measure impairment. The impairment evaluations are performed in conjunction with the ALLL process on a quarterly basis by officers in the Special Credits group, which reports to the Chief Credit Officer. The Real Estate Appraisal Services Department (“REASD”), which also reports to the Chief Credit Officer, is responsible for obtaining appraisals from third-parties or performing internal evaluations. If an appraisal is obtained from a third-party, the REASD reviews the appraisal to evaluate the adequacy of the appraisal report, including its scope, methods, accuracy, and reasonableness.
	Other real estate owned—OREO is real property that the Bank has taken ownership of in partial or full satisfaction of a loan or loans. OREO is generally measured based on the property’s fair market value as indicated by an appraisal or a letter of intent to purchase. OREO is initially recorded at the fair value less estimated costs to sell. This amount becomes the property’s new basis. Any fair value adjustments based on the property’s fair value less estimated costs to sell at the date of acquisition are charged to the ALLL, or in the event of a write-up without previous losses charged to the ALLL, a credit to earnings is recorded. Management periodically reviews OREO in an effort to ensure the property is recorded at its fair value, net of estimated costs to sell. Any fair value adjustments subsequent to acquisition are charged or credited to earnings. The initial and subsequent evaluations are performed by officers in the Special Credits group, which reports to the Chief Credit Officer. The REASD obtains appraisals from third-parties for OREO and performs internal evaluations. If an appraisal is obtained from a third-party, the REASD reviews the appraisal to evaluate the adequacy of the appraisal report, including its scope, methods, accuracy, and reasonableness.
	The following tables set forth information related to the Company’s assets that were measured using fair value estimates on a nonrecurring basis during the current and prior year quarterly periods:
		Fair value at March 31, 2015		Fair Value Measurements at Reporting Date Using							Losses During the Three Months Ended
				Level 1			Level 2		Level 3		31-Mar-15
		(in thousands)
	OREO	$	1,429	$	—		$	—	$	1,429	$	197
		$	1,429	$	—		$	—	$	1,429	$	197
		Fair value at		Fair Value Measurements at Reporting Date Using							Losses During the Three Months Ended
		March 31, 2014		Level 1			Level 2		Level 3		31-Mar-14
		(in thousands)
	Impaired loans	$	2,094	$	—		$	—	$	2,094	$	1,387
	OREO (1)	6,125		—			—		6,125		1,303
		$	8,219	$	—		$	—	$	8,219	$	2,690
	__________
	(1) Reclassified to conform to the current period’s presentation. The reclassification was limited to combining historically reported “Noncovered OREO” and “Covered OREO” into one line item for OREO.
	The losses on impaired loans disclosed above represent the amount of the specific reserve and/or charge-offs during the period applicable to loans held at period end. The amount of the specific reserve is included in the allowance for loan and lease losses. The losses on OREO disclosed above represent the write-downs taken at foreclosure that were charged to the allowance for loan and lease losses, as well as subsequent changes in any valuation allowances from updated appraisals that were recorded to earnings.
	Quantitative information about Level 3 fair value measurements
	The range and weighted-average of the significant unobservable inputs used to fair value our Level 3 nonrecurring assets, along with the valuation techniques used, are shown in the following table:
		Fair value at March 31, 2015		Valuation Technique		Unobservable Input	Range (Weighted Average) (1)
		(dollars in thousands)
	OREO	$	1,429	Fair Market Value of Collateral		Adjustment to Appraisal Value	N/A (2)
	(1) Discount applied to appraisal value, letter of intent to purchase, or stated value (in the case of accounts receivable, inventory and equipment).
(2) Quantitative disclosures are not provided for OREO because there were no adjustments made to the appraisal value during the current period.
	Fair value at		Valuation Technique		Unobservable Input	Range (Weighted Average) (1)
	March 31, 2014
	(dollars in thousands)
Impaired loans	$	990	Fair Market Value of Collateral		Adjustment to Appraisal Value	N/A (2)
Impaired loans - other collateral (3)	1,104		Fair Market Value of Collateral		Adjustment to Stated value	0% - 100% (68%)
OREO	6,125		Fair Market Value of Collateral		Adjustment to Appraisal Value	N/A (2)
(1) Discount applied to appraisal value, letter of intent to purchase, or stated value (in the case of accounts receivable, inventory and equipment).
(2) Quantitative disclosures are not provided for impaired loans collateralized by real estate and OREO because there were no adjustments made to the appraisal value during the current period.
(3) Other collateral consists of accounts receivable, inventory and equipment.
Fair value of financial instruments
Because broadly traded markets do not exist for most of the Company’s financial instruments, the fair value calculations attempt to incorporate the effect of current market conditions at a specific time. These determinations are subjective in nature, involve uncertainties and matters of significant judgment and do not include tax ramifications; therefore, the results cannot be determined with precision, substantiated by comparison to independent markets and may not be realized in an actual sale or immediate settlement of the instruments. There may be inherent weaknesses in any calculation technique, and changes in the underlying assumptions used, including discount rates and estimates of future cash flows, could significantly affect the results. For all of these reasons, the aggregation of the fair value calculations presented herein do not represent, and should not be construed to represent, the underlying value of the Company.
The following methods and assumptions were used to estimate the fair value of each class of financial instruments for which it is practicable to estimate that value:
Cash and due from banks and interest-earning deposits with banks—The fair value of financial instruments that are short-term or reprice frequently and that have little or no risk are considered to have a fair value that approximates carrying value (Level 1).
Securities available for sale—Securities at fair value, other than U.S. Treasury Notes, are priced using a combination of market activity, industry recognized information sources, yield curves, discounted cash flow models and other factors (Level 2). U.S. Treasury Notes are priced using quotes in active markets (Level 1).
Federal Home Loan Bank stock—The fair value is based upon the par value of the stock which equates to its carrying value (Level 2).
Loans—Loans are not recorded at fair value on a recurring basis. Nonrecurring fair value adjustments are periodically recorded on impaired loans that are measured for impairment based on the fair value of collateral. For most performing loans, fair value is estimated using expected duration and lending rates that would have been offered on March 31, 2015 or December 31, 2014, for loans which mirror the attributes of the loans with similar rate structures and average maturities. The fair values resulting from these calculations are reduced by an amount representing the change in estimated fair value attributable to changes in borrowers’ credit quality since the loans were originated. For nonperforming loans, fair value is estimated by applying a valuation discount based upon loan sales data from the FDIC. For PCI loans, fair value is estimated by discounting the expected future cash flows using a lending rate that would have been offered on March 31, 2015 (Level 3).
FDIC loss-sharing asset —The fair value of the FDIC loss-sharing asset is estimated based on discounting the expected future cash flows using an estimated market rate (Level 3).
Interest rate contracts—Interest rate swap positions are valued in models, which use readily observable market parameters as their basis (Level 2).
Deposits—For deposits with no contractual maturity, the fair value is equal to the carrying value (Level 1). The fair value of fixed maturity deposits is based on discounted cash flows using the difference between the deposit rate and current market rates for deposits of similar remaining maturities (Level 2).
FHLB advances—The fair value of FHLB advances is estimated based on discounting the future cash flows using the market rate currently offered (Level 2).
Repurchase Agreements—The fair value of term repurchase agreements is estimated based on discounting the future cash flows using the market rate currently offered. The carrying amount of sweep repurchase agreements approximates their fair values due to the short period of time between repricing dates (Level 2).
Other Borrowings— Other borrowings are trust preferred obligations assumed by the Company in the Intermountain acquisition. The fair value is estimated as the carrying value as these obligations are redeemable and a market participant would expect redemption in the near-term (Level 2).
Other Financial Instruments—The majority of our commitments to extend credit and standby letters of credit carry current market interest rates if converted to loans, as such, carrying value is assumed to equal fair value.
The following tables summarize carrying amounts and estimated fair values of selected financial instruments as well as assumptions used by the Company in estimating fair value at March 31, 2015 and December 31, 2014:
	March 31, 2015
	Carrying		Fair			Level 1		Level 2		Level 3
	Amount		Value
	(in thousands)
Assets
Cash and due from banks	$	177,026	$	177,026		$	177,026	$	—	$	—
Interest-earning deposits with banks	71,575		71,575			71,575		—		—
Securities available for sale	2,007,159		2,007,159			20,778		1,986,381		—
FHLB stock	33,004		33,004			—		33,004		—
Loans held for sale	3,545		3,545			—		3,545		—
Loans	5,380,661		5,540,202			—		—		5,540,202
FDIC loss-sharing asset	14,644		4,918			—		—		4,918
Interest rate contracts	14,244		14,244			—		14,244		—
Liabilities
Deposits	$	7,074,965	$	7,069,844		$	6,577,549	$	492,295	$	—
FHLB Advances	36,559		37,413			—		37,413		—
Repurchase agreements	96,852		97,868			—		97,868		—
Interest rate contracts	14,300		14,300			—		14,300		—
	December 31, 2014
	Carrying		Fair			Level 1		Level 2		Level 3
	Amount		Value
	(in thousands)
Assets
Cash and due from banks	$	171,221	$	171,221		$	171,221	$	—	$	—
Interest-earning deposits with banks	16,949		16,949			16,949		—		—
Securities available for sale	2,098,257		2,098,257			20,499		2,077,758		—
FHLB stock	33,365		33,365			—		33,365		—
Loans held for sale	1,116		1,116			—		1,116		—
Loans	5,375,809		5,516,286			—		—		5,516,286
FDIC loss-sharing asset	15,174		4,054			—		—		4,054
Interest rate contracts	11,800		11,800			—		11,800		—
Liabilities
Deposits	$	6,924,722	$	6,921,804		$	6,416,017	$	505,787	$	—
FHLB Advances	216,568		217,296			—		217,296		—
Repurchase agreements	105,080		106,171			—		106,171		—
Interest rate contracts	11,851		11,851			—		11,851		—

Earnings_per_Common_Share

Earnings per Common Share	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Earnings Per Common Share	Earnings per Common Share
	The Company applies the two-class method of computing basic and diluted EPS. Under the two-class method, EPS is determined for each class of common stock and participating security according to dividends declared and participation rights in undistributed earnings. The Company issues restricted shares under share-based compensation plans and preferred shares which qualify as participating securities.
	The following table sets forth the computation of basic and diluted earnings per share for the three months ended March 31, 2015 and 2014:
			Three Months Ended
			March 31,
			2015		2014
			(in thousands except per share)
	Basic EPS:
	Net income		$	24,361	$	19,844
	Less: Earnings allocated to participating securities
	Preferred shares		43		40
	Nonvested restricted shares		225		169
	Earnings allocated to common shareholders		$	24,093	$	19,635
	Weighted average common shares outstanding		56,965		51,097
	Basic earnings per common share		$	0.42	$	0.38
	Diluted EPS:
	Earnings allocated to common shareholders (1)		$	24,093	$	19,639
	Weighted average common shares outstanding		56,965		51,097
	Dilutive effect of equity awards		13		1,336
	Weighted average diluted common shares outstanding		56,978		52,433
	Diluted earnings per common share		$	0.42	$	0.37
	Potentially dilutive share options that were not included in the computation of diluted EPS because to do so would be anti-dilutive		53		83
	__________
	-1	Earnings allocated to common shareholders for basic and diluted EPS may differ under the two-class method as a result of adding common stock equivalents for options and warrants to dilutive shares outstanding, which alters the ratio used to allocate earnings to common shareholders and participating securities for the purposes of calculating diluted EPS.

Subsequent_Event

Subsequent Event	3 Months Ended
	Mar. 31, 2015
Subsequent Event [Line Items]
Subsequent Events [Text Block]	Subsequent Event
	Subsequent events are events or transactions that occur after the balance sheet date but before financial statements are issued. Recognized subsequent events are events or transactions that provide additional evidence about conditions that existed at the date of the balance sheet, including the estimates inherent in the process of preparing financial statements. Nonrecognized subsequent events are events that provide evidence about conditions that did not exist at the date of the balance sheet but arose after that date.
	On April 23, 2015 the Company filed an amendment to its amended and restated articles of incorporation (following shareholder approval on April 22, 2015) providing for an increase in the number of authorized common shares from 63,032,681 to 115,000,000.

Business_combinations_Tables

Business combinations (Tables)	3 Months Ended
	Mar. 31, 2015
Business Acquisition, Supplemental Pro Forma Information [Line Items]
Business Acquisition, Pro Forma Information [Table Text Block]	For illustrative purposes only, the following table presents certain unaudited pro forma information for the three month period ended March 31, 2014. This unaudited pro forma information was calculated as if Intermountain had been acquired as of the beginning of the year prior to the date of acquisition. The unaudited pro forma information combines the historical results of Intermountain with the Company’s consolidated historical results and includes certain adjustments reflecting the estimated impact of certain fair value adjustments for the respective period. The pro forma information is not indicative of what would have occurred had the acquisition occurred as of the beginning of the year prior to the acquisition. In particular, no adjustments have been made to eliminate the impact of other-than-temporary impairment losses and losses recognized on the sale of securities that may not have been necessary had the investment securities been recorded at fair value as of the beginning of the year prior to the date of acquisition. The unaudited pro forma information does not consider any changes to the provision for credit losses resulting from recording loan assets at fair value. Additionally, Columbia expects to achieve further operating cost savings and other business synergies, including revenue growth, as a result of the acquisition which are not reflected in the pro forma amounts that follow. As a result, actual amounts would have differed from the unaudited pro forma information presented.
		Unaudited Pro Forma
		Three Months Ended March 31,
		2014
		(in thousands except per share)
	Total revenues (net interest income plus noninterest income)	$	97,488
	Net income	$	21,078
	Earnings per share - basic	$	0.38
	Earnings per share - diluted	$	0.37
Intermountain Community Bancorp [Member]
Business Acquisition, Supplemental Pro Forma Information [Line Items]
Business Acquisition, Integration, Restructuring and Other Related Costs [Text Block]	The following table shows the impact of the acquisition-related expenses related to the acquisition of Intermountain for the three months ended March 31, 2015 to the various components of noninterest expense:
		Three Months Ended March 31,
		2015
		(in thousands)
	Noninterest Expense
	Compensation and employee benefits	$	273
	Occupancy	499
	Advertising and promotion	96
	Data processing and communications	1,558
	Legal and professional fees	385
	Other	91
	Total impact of acquisition-related costs to noninterest expense	$	2,902

Securities_Tables

Securities (Tables)	3 Months Ended
	Mar. 31, 2015
Available-for-sale Securities [Abstract]
Securities Available for Sale	The following table summarizes the amortized cost, gross unrealized gains and losses and the resulting fair value of securities available for sale:
		Amortized			Gross			Gross			Fair Value
		Cost			Unrealized			Unrealized
					Gains			Losses
		(in thousands)
	March 31, 2015
	U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	1,093,576		$	13,765		$	(4,641	)	$	1,102,700
	State and municipal securities	486,969			15,434			(732		)	501,671
	U.S. government agency and government-sponsored enterprise securities	375,230			2,551			(983		)	376,798
	U.S. government securities	20,918			—			(140		)	20,778
	Other securities	5,284			40			(112		)	5,212
	Total	$	1,981,977		$	31,790		$	(6,608	)	$	2,007,159
	December 31, 2014
	U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	1,160,378		$	10,219		$	(8,210	)	$	1,162,387
	State and municipal securities	483,578			14,432			(1,526		)	496,484
	U.S. government agency and government-sponsored enterprise securities	416,919			856			(4,069		)	413,706
	U.S. government securities	20,910			—			(411		)	20,499
	Other securities	5,284			20			(123		)	5,181
	Total	$	2,087,069		$	25,527		$	(14,339	)	$	2,098,257
Schedule of gross realized gains and losses on sales and calls of securities available for sale	The following table provides the gross realized gains and losses on the sales of securities for the periods indicated:
		Three Months Ended
		March 31,
		2015			2014
		(in thousands)
	Gross realized gains	$	730		$	223
	Gross realized losses	(9		)	—
	Net realized gains	$	721		$	223
Schedule of Contractual Maturities of Investment Securities Available for Sale	The scheduled contractual maturities of investment securities available for sale at March 31, 2015 are presented as follows:
		March 31, 2015
		Amortized Cost			Fair Value
		(in thousands)
	Due within one year	$	15,480		$	15,601
	Due after one year through five years	404,752			406,989
	Due after five years through ten years	526,230			534,584
	Due after ten years	1,030,231			1,044,773
	Other securities with no stated maturity	5,284			5,212
	Total investment securities available-for-sale	$	1,981,977		$	2,007,159
Carrying Value of Securities Pledged As Collateral	The following table summarizes the carrying value of securities pledged as collateral to secure public deposits, borrowings and other purposes as permitted or required by law:
		March 31, 2015
		(in thousands)
	Washington and Oregon State to secure public deposits	$	323,771
	Federal Reserve Bank to secure borrowings	36,945
	Other securities pledged	156,385
	Total securities pledged as collateral	$	517,101
Summary of Gross Unrealized Losses and Fair Value of the Investments with Unrealized Losses	The following table shows the gross unrealized losses and fair value of the Company’s investments with unrealized losses that are not deemed to be other-than-temporarily impaired, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at March 31, 2015 and December 31, 2014:
		Less than 12 Months						12 Months or More						Total
		Fair			Unrealized			Fair			Unrealized			Fair		Unrealized
		Value			Losses			Value			Losses			Value		Losses
		(in thousands)
	March 31, 2015
	U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	94,304		$	(634	)	$	213,050		$	(4,007	)	$	307,354	$	(4,641	)
	State and municipal securities	45,809			(227		)	31,597			(505		)	77,406		(732		)
	U.S. government agency and government-sponsored enterprise securities	999			(1		)	178,013			(982		)	179,012		(983		)
	U.S. government securities	1,050			(1		)	19,728			(139		)	20,778		(140		)
	Other securities	—			—			2,843			(112		)	2,843		(112		)
	Total	$	142,162		$	(863	)	$	445,231		$	(5,745	)	$	587,393	$	(6,608	)
	December 31, 2014
	U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	258,825		$	(1,287	)	$	279,015		$	(6,924	)	$	537,840	$	(8,211	)
	State and municipal securities	71,026			(543		)	44,148			(982		)	115,174		(1,525		)
	U.S. government agency and government-sponsored enterprise securities	105,250			(518		)	216,221			(3,551		)	321,471		(4,069		)
	U.S. government securities	—			—			19,450			(411		)	19,450		(411		)
	Other securities	2,313			(2		)	2,834			(121		)	5,147		(123		)
	Total	$	437,414		$	(2,350	)	$	561,668		$	(11,989	)	$	999,082	$	(14,339	)

Loans_Tables

Loans (Tables)	3 Months Ended
	Mar. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Analysis of Loan Portfolio by Major Types of Loans
		March 31, 2015											December 31, 2014
		Loans, excluding PCI loans				PCI Loans				Total			Loans, excluding PCI loans			PCI Loans			Total
		(in thousands)
	Commercial business	$	2,139,873			$	46,335			$	2,186,208		$	2,119,565		$	44,505		$	2,164,070
	Real estate:
	One-to-four family residential	173,739				26,601				200,340			175,571			26,993			202,564
	Commercial and multifamily residential	2,374,454				118,230				2,492,684			2,363,541			128,769			2,492,310
	Total real estate	2,548,193				144,831				2,693,024			2,539,112			155,762			2,694,874
	Real estate construction:
	One-to-four family residential	124,017				3,797				127,814			116,866			4,021			120,887
	Commercial and multifamily residential	119,880				2,238				122,118			134,443			2,321			136,764
	Total real estate construction	243,897				6,035				249,932			251,309			6,342			257,651
	Consumer	352,960				22,638				375,598			364,182			23,975			388,157
	Less: Net unearned income	(53,867		)		—				(53,867		)	(59,374		)	—			(59,374		)
	Total loans, net of unearned income	5,231,056				219,839				5,450,895			5,214,794			230,584			5,445,378
	Less: Allowance for loan and lease losses	(53,703		)		(16,531		)		(70,234		)	(53,233		)	(16,336		)	(69,569		)
	Total loans, net	$	5,177,353			$	203,308			$	5,380,661		$	5,161,561		$	214,248		$	5,375,809
	Loans held for sale	$	3,545			$	—			$	3,545		$	1,116		$	—		$	1,116
Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Analysis of Nonaccrual Loans	The following is an analysis of nonaccrual loans as of March 31, 2015 and December 31, 2014:
		March 31, 2015								December 31, 2014
		Recorded				Unpaid Principal				Recorded			Unpaid Principal
		Investment				Balance				Investment			Balance
		Nonaccrual				Nonaccrual				Nonaccrual			Nonaccrual
		Loans				Loans				Loans			Loans
		(in thousands)
	Commercial business:
	Secured	$	17,240			$	20,573			$	16,552		$	21,453
	Unsecured	189				211				247			269
	Real estate:
	One-to-four family residential	4,429				6,109				2,822			5,680
	Commercial & multifamily residential:
	Commercial land	1,616				1,560				821			1,113
	Income property	887				887				3,200			5,521
	Owner occupied	1,995				2,036				3,826			5,837
	Real estate construction:
	One-to-four family residential:
	Land and acquisition	871				871				95			112
	Residential construction	1,263				1,263				370			370
	Commercial & multifamily residential:
	Owner occupied	470				489				480			489
	Consumer	2,868				3,799				2,939			3,930
	Total	$	31,828			$	37,798			$	31,352		$	44,774
Analysis of the Aged Loan Portfolio	March 31, 2015 and December 31, 2014:
		Current				30 - 59				60 - 89			Greater			Total			Nonaccrual			Total Loans
		Loans				Days				Days			than 90			Past Due			Loans
						Past Due				Past Due			Days Past
													Due
	March 31, 2015	(in thousands)
	Commercial business:
	Secured	$	2,024,277			$	11,910			$	1,874		$	58		$	13,842		$	17,240		$	2,055,359
	Unsecured	78,351				492				120			67			679			189			79,219
	Real estate:
	One-to-four family residential	164,962				771				124			21			916			4,429			170,307
	Commercial & multifamily residential:
	Commercial land	186,904				4,303				355			264			4,922			1,616			193,442
	Income property	1,305,595				2,502				560			—			3,062			887			1,309,544
	Owner occupied	841,551				2,206				435			—			2,641			1,995			846,187
	Real estate construction:
	One-to-four family residential:
	Land and acquisition	15,860				67				—			—			67			871			16,798
	Residential construction	104,378				—				—			4			4			1,263			105,645
	Commercial & multifamily residential:
	Income property	62,958				—				—			—			—			—			62,958
	Owner occupied	54,969				—				—			—			—			470			55,439
	Consumer	331,566				1,509				193			22			1,724			2,868			336,158
	Total	$	5,171,371			$	23,760			$	3,661		$	436		$	27,857		$	31,828		$	5,231,056
		Current				30 - 59				60 - 89			Greater			Total			Nonaccrual			Total Loans
		Loans				Days				Days			than 90			Past Due			Loans
						Past Due				Past Due			Days Past
													Due
	December 31, 2014	(in thousands)
	Commercial business:
	Secured	$	2,004,418			$	5,137			$	6,149		$	1,372		$	12,658		$	16,552		$	2,033,628
	Unsecured	79,661				185				—			—			185			247			80,093
	Real estate:
	One-to-four family residential	167,197				1,700				45			—			1,745			2,822			171,764
	Commercial & multifamily residential:
	Commercial land	187,470				1,454				34			—			1,488			821			189,779
	Income property	1,294,982				3,031				786			—			3,817			3,200			1,301,999
	Owner occupied	839,689				937				289			—			1,226			3,826			844,741
	Real estate construction:
	One-to-four family residential:
	Land and acquisition	15,462				953				—			—			953			95			16,510
	Residential construction	97,821				326				—			4			330			370			98,521
	Commercial & multifamily residential:
	Income property	73,783				—				—			—			—			—			73,783
	Owner occupied	57,470				—				994			—			994			480			58,944
	Consumer	341,032				933				118			10			1,061			2,939			345,032
	Total	$	5,158,985			$	14,656			$	8,415		$	1,386		$	24,457		$	31,352		$	5,214,794
Impaired Financing Receivables	The following is an analysis of impaired loans as of March 31, 2015 and December 31, 2014:
		Recorded Investment				Recorded Investment				Impaired Loans With									Impaired Loans Without
		of Loans				of Loans				Recorded Allowance									Recorded Allowance
		Collectively Measured				Individually
		for Contingency				Measured for
		Provision				Specific
						Impairment				Recorded			Unpaid			Related			Recorded			Unpaid
										Investment			Principal			Allowance			Investment			Principal
													Balance									Balance
	March 31, 2015	(in thousands)
	Commercial business:
	Secured	$	2,044,486			$	10,873			$	96		$	96		$	24		$	10,777		$	12,986
	Unsecured	79,219				—				—			—			—			—			—
	Real estate:
	One-to-four family residential	166,129				4,178				420			461			115			3,758			4,220
	Commercial & multifamily residential:
	Commercial land	192,972				470				—			—			—			470			470
	Income property	1,307,556				1,988				—			—			—			1,988			2,355
	Owner occupied	839,157				7,030				578			578			24			6,452			8,944
	Real estate construction:
	One-to-four family residential:
	Land and acquisition	15,818				980				109			108			67			871			871
	Residential construction	104,752				893				—			—			—			893			893
	Commercial & multifamily residential:
	Income property	62,958				—				—			—			—			—			—
	Owner occupied	55,439				—				—			—			—			—			—
	Consumer	335,474				684				—			—			—			684			895
	Total	$	5,203,960			$	27,096			$	1,203		$	1,243		$	230		$	25,893		$	31,634
		Recorded Investment				Recorded Investment				Impaired Loans With									Impaired Loans Without
		of Loans				of Loans				Recorded Allowance									Recorded Allowance
		Collectively Measured				Individually
		for Contingency				Measured for
		Provision				Specific
						Impairment				Recorded			Unpaid			Related			Recorded			Unpaid
										Investment			Principal			Allowance			Investment			Principal
													Balance									Balance
	December 31, 2014	(in thousands)
	Commercial business:
	Secured	$	2,023,104			$	10,524			$	99		$	99		$	25		$	10,425		$	12,410
	Unsecured	80,091				2				2			2			2			—			—
	Real estate:
	One-to-four family residential	169,619				2,145				424			465			120			1,721			2,370
	Commercial & multifamily residential:
	Commercial land	189,779				—				—			—			—			—			—
	Income property	1,295,650				6,349				—			—			—			6,349			10,720
	Owner occupied	835,895				8,846				582			582			27			8,264			12,732
	Real estate construction:
	One-to-four family residential:
	Land and acquisition	16,401				109				109			109			67			—			—
	Residential construction	98,521				—				—			—			—			—			—
	Commercial & multifamily residential:
	Income property	73,783				—				—			—			—			—			—
	Owner occupied	58,944				—				—			—			—			—			—
	Consumer	344,908				124				—			—			—			124			201
	Total	$	5,186,695			$	28,099			$	1,216		$	1,257		$	241		$	26,883		$	38,433
	The following table provides additional information on impaired loans for the three month periods indicated:
		Three Months Ended March 31,
		2015								2014
		Average Recorded				Interest Recognized				Average Recorded			Interest Recognized
		Investment				on				Investment			on
		Impaired Loans				Impaired Loans				Impaired Loans			Impaired Loans
		(in thousands)
	Commercial business:
	Secured	$	10,698			$	7			$	6,232		$	17
Unsecured	1				—				31			—
Real estate:
One-to-four family residential	3,162				13				1,856			13
Commercial & multifamily residential:
Commercial land	235				—				111			—
Income property	4,168				10				6,436			62
Owner occupied	7,938				234				10,140			241
Real estate construction:
One-to-four family residential:
Land and acquisition	544				1				1,569			1
Residential construction	446				—				—			—
Consumer	404				2				163			2
Total	$	27,596			$	267			$	26,538		$	336
Analysis of loans classified as Troubled Debt Restructurings (bTDRb)
		Three Months Ended March 31,
		2015								2014
		Average Recorded				Interest Recognized				Average Recorded			Interest Recognized
		Investment				on				Investment			on
		Impaired Loans				Impaired Loans				Impaired Loans			Impaired Loans
		(in thousands)
	Commercial business:
	Secured	$	10,698			$	7			$	6,232		$	17
	Unsecured	1				—				31			—
	Real estate:
	One-to-four family residential	3,162				13				1,856			13
	Commercial & multifamily residential:
	Commercial land	235				—				111			—
	Income property	4,168				10				6,436			62
	Owner occupied	7,938				234				10,140			241
	Real estate construction:
	One-to-four family residential:
	Land and acquisition	544				1				1,569			1
	Residential construction	446				—				—			—
	Consumer	404				2				163			2
	Total	$	27,596			$	267			$	26,538		$	336
	There were no troubled debt restructurings (“TDR”) during the three months ended March 31, 2015. The following is an analysis of loans classified as TDR during the three months ended March 31, 2014:
		Three months ended March 31, 2014
		Number of TDR Modifications			Pre-Modification				Post-Modification
					Outstanding				Outstanding
					Recorded				Recorded
					Investment				Investment
		(dollars in thousands)
	Commercial business:
	Secured	2			$	546			$	546
	Real estate:
	One-to-four family residential	2			494				494
	Commercial and multifamily residential:
	Income property	1			143				126
	Total	5			$	1,183			$	1,166
Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Analysis of Loan Portfolio by Major Types of Loans	The following is an analysis of our PCI loans, net of related allowance for losses and remaining valuation discounts as of March 31, 2015 and December 31, 2014:
		March 31, 2015				December 31, 2014
		(in thousands)
	Commercial business	$	52,115			$	50,334
	Real estate:
	One-to-four family residential	31,127				31,981
	Commercial and multifamily residential	127,952				140,398
	Total real estate	159,079				172,379
	Real estate construction:
	One-to-four family residential	4,026				4,353
	Commercial and multifamily residential	2,501				2,588
	Total real estate construction	6,527				6,941
	Consumer	25,390				26,814
	Subtotal of PCI loans	243,111				256,468
	Less:
	Valuation discount resulting from acquisition accounting	23,272				25,884
	Allowance for loan losses	16,531				16,336
	PCI loans, net of allowance for loan losses	$	203,308			$	214,248
Changes in Accretable Yield for Acquired Loans	The following table shows the changes in accretable yield for PCI loans for the three months ended March 31, 2015 and 2014:
		Three Months Ended March 31,
		2015				2014
		(in thousands)
	Balance at beginning of period	$	73,849			$	103,907
	Accretion	(6,319		)		(10,569		)
	Disposals	(1,093		)		(2,826		)
	Reclassifications from nonaccretable difference	2,289				11,031
	Balance at end of period	$	68,726			$	101,543

Allowance_for_Loan_and_Lease_L1

Allowance for Loan and Lease Losses and Unfunded Commitments and Letters of Credit (Tables)	3 Months Ended
	Mar. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Credit Losses on Financing Receivables	The following tables show a detailed analysis of the ALLL for the three months ended March 31, 2015 and 2014:
		Beginning		Charge-offs			Recoveries		Provision (Recovery)			Ending		Specific		General
		Balance										Balance		Reserve		Allocation
	Three months ended March 31, 2015	(in thousands)
	Commercial business:
	Secured	$	25,923	$	(1,386	)	$	512	$	712		$	25,761	$	24	$	25,737
	Unsecured	927		(40		)	106		19			1,012		—		1,012
	Real estate:
	One-to-four family residential	2,281		(8		)	12		(921		)	1,364		115		1,249
	Commercial & multifamily residential:
	Commercial land	799		—			—		28			827		—		827
	Income property	9,159		—			3,252		(3,971		)	8,440		—		8,440
	Owner occupied	5,007		—			9		596			5,612		24		5,588
	Real estate construction:
	One-to-four family residential:
	Land and acquisition	1,197		—			2		(173		)	1,026		67		959
	Residential construction	1,860		—			26		(96		)	1,790		—		1,790
	Commercial & multifamily residential:
	Income property	622		—			3		202			827		—		827
	Owner occupied	434		—			—		65			499		—		499
	Consumer	3,180		(891		)	273		273			2,835		—		2,835
	Purchased credit impaired	16,336		(4,100		)	1,686		2,609			16,531		—		16,531
	Unallocated	1,844		—			—		1,866			3,710		—		3,710
	Total	$	69,569	$	(6,425	)	$	5,881	$	1,209		$	70,234	$	230	$	70,004
		Beginning		Charge-offs			Recoveries		Provision (Recovery)			Ending		Specific		General
		Balance										Balance		Reserve		Allocation
	Three months ended March 31, 2014	(in thousands)
	Commercial business:
	Secured	$	31,027	$	(198	)	$	448	$	(2,476	)	$	28,801	$	1,521	$	27,280
	Unsecured	696		(35		)	42		43			746		27		719
	Real estate:
	One-to-four family residential	1,252		(207		)	28		121			1,194		133		1,061
	Commercial & multifamily residential:
	Commercial land	489		—			17		73			579		—		579
	Income property	9,234		—			13		860			10,107		—		10,107
	Owner occupied	3,605		(1,023		)	9		1,969			4,560		38		4,522
	Real estate construction:
	One-to-four family residential:
	Land and acquisition	610		—			39		(69		)	580		71		509
	Residential construction	822		—			3		(129		)	696		—		696
	Commercial & multifamily residential:
	Income property	285		—			—		35			320		—		320
	Owner occupied	58		—			—		96			154		—		154
	Consumer	2,547		(727		)	253		564			2,637		3		2,634
	Purchased credit impaired	20,174		(4,273		)	1,806		2,422			20,129		—		20,129
	Unallocated	1,655		—			—		(1,587		)	68		—		68
	Total	$	72,454	$	(6,463	)	$	2,658	$	1,922		$	70,571	$	1,793	$	68,778
Changes in the Allowance for Unfunded Commitments and Letters of Credit	Changes in the allowance for unfunded commitments and letters of credit, a component of other liabilities in the consolidated balance sheet, are summarized as follows:
		Three Months Ended
		March 31,
		2015		2014
		(in thousands)
	Balance at beginning of period	$	2,655	$	2,505
	Net changes in the allowance for unfunded commitments and letters of credit	—		(50		)
	Balance at end of period	$	2,655	$	2,455
Financing Receivable Credit Quality Indicators	The following is an analysis of the credit quality of our loan portfolio, excluding PCI loans, as of March 31, 2015 and December 31, 2014:
		Pass		Special Mention			Substandard		Doubtful			Loss		Total
	March 31, 2015	(in thousands)
	Loans, excluding PCI loans:
	Commercial business:
	Secured	$	1,995,680	$	19,210		$	40,469	$	—		$	—	$	2,055,359
	Unsecured	78,498		—			721		—			—		79,219
	Real estate:
	One-to-four family residential	162,448		1,465			6,394		—			—		170,307
	Commercial and multifamily residential:
	Commercial land	187,519		3,459			2,464		—			—		193,442
	Income property	1,301,779		3,517			4,248		—			—		1,309,544
	Owner occupied	828,244		1,757			16,186		—			—		846,187
	Real estate construction:
	One-to-four family residential:
	Land and acquisition	16,180		166			452		—			—		16,798
	Residential construction	103,257		680			1,708		—			—		105,645
	Commercial and multifamily residential:
	Income property	62,958		—			—		—			—		62,958
	Owner occupied	54,563		—			876		—			—		55,439
	Consumer	331,413		—			4,745		—			—		336,158
	Total	$	5,122,539	$	30,254		$	78,263	$	—		$	—	5,231,056
	Less:
	Allowance for loan and lease losses													53,703
	Loans, excluding PCI loans, net													$	5,177,353
		Pass		Special Mention			Substandard		Doubtful			Loss		Total
	December 31, 2014	(in thousands)
	Loans, excluding PCI loans:
	Commercial business:
	Secured	$	1,963,210	$	15,790		$	54,628	$	—		$	—	$	2,033,628
	Unsecured	79,534		—			559		—			—		80,093
	Real estate:
	One-to-four family residential	163,914		55			7,795		—			—		171,764
	Commercial and multifamily residential:
	Commercial land	183,701		4,217			1,861		—			—		189,779
	Income property	1,287,729		5,885			8,385		—			—		1,301,999
	Owner occupied	825,694		7,876			11,171		—			—		844,741
	Real estate construction:
	One-to-four family residential:
	Land and acquisition	15,307		167			1,036		—			—		16,510
	Residential construction	96,031		909			1,581		—			—		98,521
	Commercial and multifamily residential:
	Income property	73,783		—			—		—			—		73,783
	Owner occupied	58,055		—			889		—			—		58,944
	Consumer	339,695		68			5,269		—			—		345,032
	Total	$	5,086,653	$	34,967		$	93,174	$	—		$	—	5,214,794
	Less:
	Allowance for loan and lease losses													53,233
	Loans, excluding PCI loans, net													$	5,161,561
	The following is an analysis of the credit quality of our PCI loan portfolio as of March 31, 2015 and December 31, 2014:
		Pass		Special Mention			Substandard		Doubtful			Loss		Total
	March 31, 2015	(in thousands)
	PCI loans:
	Commercial business:
	Secured	$	39,919	$	1,040		$	9,060	$	—		$	—	$	50,019
	Unsecured	2,057		—			39		—			—		2,096
	Real estate:
	One-to-four family residential	27,881		—			3,246		—			—		31,127
	Commercial and multifamily residential:
	Commercial land	8,739		—			1,668		—			—		10,407
	Income property	45,298		—			12,031		—			—		57,329
	Owner occupied	56,004		336			3,876		—			—		60,216
	Real estate construction:
	One-to-four family residential:
Land and acquisition	1,452		—			894		—			—		2,346
Residential construction	732		—			948		—			—		1,680
Commercial and multifamily residential:
Income property	1,359		—			224		—			—		1,583
Owner occupied	918		—			—		—			—		918
Consumer	23,431		—			1,959		—			—		25,390
Total	$	207,790	$	1,376		$	33,945	$	—		$	—	243,111
Less:
Valuation discount resulting from acquisition accounting													23,272
Allowance for loan losses													16,531
PCI loans, net													$	203,308
	Pass		Special Mention			Substandard		Doubtful			Loss		Total
December 31, 2014	(in thousands)
PCI loans:
Commercial business:
Secured	$	37,927	$	937		$	9,223	$	—		$	—	$	48,087
Unsecured	2,156		—			91		—			—		2,247
Real estate:
One-to-four family residential	28,822		—			3,159		—			—		31,981
Commercial and multifamily residential:
Commercial land	9,104		—			6,240		—			—		15,344
Income property	51,435		1,892			7,186		—			—		60,513
Owner occupied	58,629		346			5,566		—			—		64,541
Real estate construction:
One-to-four family residential:
Land and acquisition	1,595		—			913		—			—		2,508
Residential construction	741		—			1,104		—			—		1,845
Commercial and multifamily residential:
Income property	1,435		—			227		—			—		1,662
Owner occupied	926		—			—		—			—		926
Consumer	24,037		—			2,777		—			—		26,814
Total	$	216,807	$	3,175		$	36,486	$	—		$	—	256,468
Less:
Valuation discount resulting from acquisition accounting													25,884
Allowance for loan losses													16,336
PCI loans, net													$	214,248

Other_Real_Estate_Owned_Tables

Other Real Estate Owned (Tables)	3 Months Ended
	Mar. 31, 2015
Other Real Estate, Foreclosed Assets, and Repossessed Assets [Abstract]
Summary of Other Real Estate Owned	The following tables set forth activity in OREO for the three months ended March 31, 2015 and 2014:
		Three Months Ended March 31,
		2015			2014
		(in thousands)
	Balance, beginning of period	$	22,190		$	35,927
	Transfers in	4,692			5,751
	Valuation adjustments	(197		)	(1,580		)
	Proceeds from sale of OREO property	(5,122		)	(11,205		)
	Gain on sale of OREO, net	1,736			1,659
	Balance, end of period	$	23,299		$	30,552

Covered_Assets_and_FDIC_Losssh1

Covered Assets and FDIC Loss-sharing Asset (Tables)	3 Months Ended
	Mar. 31, 2015
Covered Assets And FDIC Loss Sharing Asset [Line Items]
FDIC Loss-sharing Asset	The following table shows a detailed analysis of the FDIC loss-sharing asset for the three months ended March 31, 2015 and 2014:
		Three Months Ended March 31,
		2015			2014
		(in thousands)
	Balance at beginning of period	$	15,174		$	39,846
	Adjustments not reflected in income:
	Cash payments to (from) the FDIC	(659		)	1,678
	FDIC reimbursable losses (recoveries), net	(21		)	132
	Adjustments reflected in income:
	Amortization, net	(2,294		)	(6,452		)
	Loan impairment	1,532			1,938
	Sale of other real estate	(420		)	(756		)
	Write-downs of other real estate	1,071			516
	Other	261			(65		)
	Balance at end of period	$	14,644		$	36,837
Schedule of FDIC Loss-Sharing Agreements and Covered Assets [Table Text Block]	The following table presents information about the composition of the FDIC loss-sharing asset, the clawback liability, and the non-single family and the single family covered assets as of the date indicated:
		March 31, 2015
		Columbia River Bank			American Marine Bank			Summit Bank		First Heritage Bank		Total
		(in thousands)
	FDIC loss-sharing asset	$	2,124		$	4,824		$	4,162	$	3,534	$	14,644
	Clawback liability	$	4,063		$	136		$	—	$	—	$	4,199
	Non-single family covered assets	$	107,135		$	16,914		$	13,856	$	22,763	$	160,668
	Single family covered assets	$	9,994		$	26,391		$	6,322	$	2,479	$	45,186
	Loss-sharing expiration dates:
	Non-single family	First Quarter 2015			First Quarter 2015			Second Quarter 2016		Second Quarter 2016
	Single family	First Quarter 2020			First Quarter 2020			Second Quarter 2021		Second Quarter 2021
	Loss recovery expiration dates:
	Non-single family	First Quarter 2018			First Quarter 2018			Second Quarter 2019		Second Quarter 2019
	Single family	First Quarter 2020			First Quarter 2020			Second Quarter 2021		Second Quarter 2021

Goodwill_and_Intangible_Assets1

Goodwill and Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill and Intangible Assets	The following table sets forth activity for goodwill and other intangible assets for the periods indicated:
		Three Months Ended March 31,
		2015			2014
		(in thousands)
	Goodwill
	Total goodwill (1)	$	382,537		$	343,952
	Other intangible assets, net
	Core deposit intangible:
	Gross core deposit intangible balance at beginning of period (1)	58,598			47,698
	Accumulated amortization at beginning of period	(29,058		)	(22,765		)
	Core deposit intangible, net at beginning of period	29,540			24,933
	CDI current period amortization	(1,817		)	(1,579		)
	Total core deposit intangible, net at end of period	27,723			23,354
	Intangible assets not subject to amortization	919			919
	Other intangible assets, net at end of period	28,642			24,273
	Total goodwill and other intangible assets at end of period	$	411,179		$	368,225
Estimated Future Amortization Expense of Core Deposit Intangibles	The following table provides the estimated future amortization expense of core deposit intangibles for the remaining nine months ending December 31, 2015 and the succeeding four years:
		Amount
		(in thousands)
	Year ending December 31,
	2015	$	5,065
	2016	5,945
	2017	4,913
	2018	3,855
	2019	2,951

Derivatives_and_Balance_Sheet_1

Derivatives and Balance Sheet Offsetting (Tables)	3 Months Ended
	Mar. 31, 2015
Derivative [Line Items]
Balance Sheet Offsetting [Table Text Block]	The following tables show the gross interest rate swap agreements and repurchase agreements in the consolidated balance sheets and the respective collateral received or pledged in the form of other financial instruments, which are generally marketable securities. The collateral amounts in these tables are limited to the outstanding balances of the related asset or liability. Therefore, instances of overcollateralization are not shown.
		Gross Amounts of Recognized Assets/Liabilities				Gross Amounts Offset in the Consolidated Balance Sheets			Net Amounts of Assets/Liabilities Presented in the Consolidated Balance Sheets		Gross Amounts Not Offset in the Consolidated Balance Sheets
											Collateral Posted				Net Amount
	March 31, 2015	(in thousands)
	Assets
	Interest rate contracts	$	14,244			$	—		$	14,244	$	—			$	14,244
	Liabilities
	Interest rate contracts	$	14,300			$	—		$	14,300	$	(14,300	)		$	—
	Repurchase agreements	$	96,852			$	—		$	96,852	$	(96,852	)		$	—
	December 31, 2014
	Assets
	Interest rate contracts	$	11,800			$	—		$	11,800	$	—			$	11,800
	Liabilities
	Interest rate contracts	$	11,851			$	—		$	11,851	$	(11,851	)		$	—
	Repurchase agreements	$	105,080			$	—		$	105,080	$	(105,080	)		$	—
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	The following table presents the fair value of derivatives not designated as hedging instruments at March 31, 2015 and December 31, 2014:
		Asset Derivatives									Liability Derivatives
		March 31, 2015						December 31, 2014			March 31, 2015						December 31, 2014
		Balance Sheet		Fair Value				Balance Sheet	Fair Value		Balance Sheet		Fair Value				Balance Sheet	Fair Value
		Location						Location			Location						Location
		(in thousands)
	Interest rate contracts	Other assets		$	14,244			Other assets	$	11,800	Other liabilities		$	14,300			Other liabilities	$	11,851

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Income (Tables)	3 Months Ended
	Mar. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	The following table shows changes in accumulated other comprehensive income (loss) by component for the three month periods ended March 31, 2015 and 2014:
		Unrealized Gains and Losses on Available-for-Sale Securities (1)			Unrealized Gains and Losses on Pension Plan Liability (1)			Total (1)
	Three months ended March 31, 2015	(in thousands)
	Beginning balance	$	7,462		$	(1,841	)	$	5,621
	Other comprehensive income (loss) before reclassifications	9,376			(280		)	9,096
	Amounts reclassified from accumulated other comprehensive income (loss) (2)	(459		)	28			(431		)
	Net current-period other comprehensive income (loss)	8,917			(252		)	8,665
	Ending balance	$	16,379		$	(2,093	)	$	14,286
	Three months ended March 31, 2014
	Beginning balance	$	(10,108	)	$	(1,936	)	$	(12,044	)
	Other comprehensive income before reclassifications	7,119			—			7,119
	Amounts reclassified from accumulated other comprehensive income (2)	(142		)	24			(118		)
	Net current-period other comprehensive income	6,977			24			7,001
	Ending balance	$	(3,131	)	$	(1,912	)	$	(5,043	)
	__________
	(1) All amounts are net of tax. Amounts in parenthesis indicate debits.
	(2) See following table for details about these reclassifications.
Schedule of reclassifications from accumulated other comprehensive income [Table Text Block]	The following table shows details regarding the reclassifications from accumulated other comprehensive income (loss) for the three month periods ended March 31, 2015 and 2014:
		Amount Reclassified from Accumulated Other Comprehensive Income (Loss)
		Three Months Ended March 31,						Affected line Item in the Consolidated
		2015			2014			Statement of Income
		(in thousands)
	Unrealized gains and losses on available-for-sale securities
	Investment securities gains	$	721		$	223		Investment securities gains, net
		721			223			Total before tax
		(262		)	(81		)	Income tax provision
		$	459		$	142		Net of tax
	Amortization of pension plan liability
	Actuarial losses	$	(44	)	$	(37	)	Compensation and employee benefits
		(44		)	(37		)	Total before tax
		16			13			Income tax benefit
		$	(28	)	$	(24	)	Net of tax

Fair_Value_Accounting_and_Meas1

Fair Value Accounting and Measurement (Tables)	3 Months Ended
	Mar. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets And Liabilities Accounted For Fair Value On Recurring Basis	The following table sets forth the Company’s financial assets and liabilities that were accounted for at fair value on a recurring basis at March 31, 2015 and December 31, 2014 by level within the fair value hierarchy. Financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement:
		Fair value		Fair Value Measurements at Reporting Date Using
				Level 1			Level 2		Level 3
	March 31, 2015	(in thousands)
	Assets
	Securities available for sale:
	U.S. government agency and government-sponsored enterprise mortgage-back securities and collateralized mortgage obligations	$	1,102,700	$	—		$	1,102,700	$	—
	State and municipal debt securities	501,671		—			501,671		—
	U.S. government agency and government-sponsored enterprise securities	376,798		—			376,798		—
	U.S. government securities	20,778		20,778			—		—
	Other securities	5,212		—			5,212		—
	Total securities available for sale	$	2,007,159	$	20,778		$	1,986,381	$	—
	Other assets (Interest rate contracts)	$	14,244	$	—		$	14,244	$	—
	Liabilities
	Other liabilities (Interest rate contracts)	$	14,300	$	—		$	14,300	$	—
		Fair value		Fair Value Measurements at Reporting Date Using
				Level 1			Level 2		Level 3
	December 31, 2014	(in thousands)
	Assets
	Securities available for sale:
	U.S. government agency and government-sponsored enterprise mortgage-back securities and collateralized mortgage obligations	$	1,162,387	$	—		$	1,162,387	$	—
	State and municipal debt securities	496,484		—			496,484		—
	U.S. government agency and government-sponsored enterprise securities	413,706		—			413,706		—
	U.S. government securities	20,499		20,499			—		—
	Other securities	5,181		—			5,181		—
	Total securities available for sale	$	2,098,257	$	20,499		$	2,077,758	$	—
	Other assets (Interest rate contracts)	$	11,800	$	—		$	11,800	$	—
	Liabilities
	Other liabilities (Interest rate contracts)	$	11,851	$	—		$	11,851	$	—
Financial Assets Accounted For Fair Value On Nonrecurring Basis	The following tables set forth information related to the Company’s assets that were measured using fair value estimates on a nonrecurring basis during the current and prior year quarterly periods:
		Fair value at March 31, 2015		Fair Value Measurements at Reporting Date Using							Losses During the Three Months Ended
				Level 1			Level 2		Level 3		31-Mar-15
		(in thousands)
	OREO	$	1,429	$	—		$	—	$	1,429	$	197
		$	1,429	$	—		$	—	$	1,429	$	197
		Fair value at		Fair Value Measurements at Reporting Date Using							Losses During the Three Months Ended
		March 31, 2014		Level 1			Level 2		Level 3		31-Mar-14
		(in thousands)
	Impaired loans	$	2,094	$	—		$	—	$	2,094	$	1,387
	OREO (1)	6,125		—			—		6,125		1,303
		$	8,219	$	—		$	—	$	8,219	$	2,690
Fair Value, by Balance Sheet Grouping	The following tables summarize carrying amounts and estimated fair values of selected financial instruments as well as assumptions used by the Company in estimating fair value at March 31, 2015 and December 31, 2014:
		March 31, 2015
		Carrying		Fair			Level 1		Level 2		Level 3
		Amount		Value
		(in thousands)
	Assets
	Cash and due from banks	$	177,026	$	177,026		$	177,026	$	—	$	—
	Interest-earning deposits with banks	71,575		71,575			71,575		—		—
	Securities available for sale	2,007,159		2,007,159			20,778		1,986,381		—
	FHLB stock	33,004		33,004			—		33,004		—
	Loans held for sale	3,545		3,545			—		3,545		—
	Loans	5,380,661		5,540,202			—		—		5,540,202
	FDIC loss-sharing asset	14,644		4,918			—		—		4,918
	Interest rate contracts	14,244		14,244			—		14,244		—
	Liabilities
	Deposits	$	7,074,965	$	7,069,844		$	6,577,549	$	492,295	$	—
	FHLB Advances	36,559		37,413			—		37,413		—
	Repurchase agreements	96,852		97,868			—		97,868		—
	Interest rate contracts	14,300		14,300			—		14,300		—
		December 31, 2014
		Carrying		Fair			Level 1		Level 2		Level 3
		Amount		Value
		(in thousands)
	Assets
	Cash and due from banks	$	171,221	$	171,221		$	171,221	$	—	$	—
	Interest-earning deposits with banks	16,949		16,949			16,949		—		—
	Securities available for sale	2,098,257		2,098,257			20,499		2,077,758		—
	FHLB stock	33,365		33,365			—		33,365		—
	Loans held for sale	1,116		1,116			—		1,116		—
	Loans	5,375,809		5,516,286			—		—		5,516,286
	FDIC loss-sharing asset	15,174		4,054			—		—		4,054
	Interest rate contracts	11,800		11,800			—		11,800		—
	Liabilities
	Deposits	$	6,924,722	$	6,921,804		$	6,416,017	$	505,787	$	—
	FHLB Advances	216,568		217,296			—		217,296		—
	Repurchase agreements	105,080		106,171			—		106,171		—
	Interest rate contracts	11,851		11,851			—		11,851		—
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Assets, Quantitative Information	The range and weighted-average of the significant unobservable inputs used to fair value our Level 3 nonrecurring assets, along with the valuation techniques used, are shown in the following table:
		Fair value at March 31, 2015		Valuation Technique		Unobservable Input	Range (Weighted Average) (1)
		(dollars in thousands)
	OREO	$	1,429	Fair Market Value of Collateral		Adjustment to Appraisal Value	N/A (2)
	(1) Discount applied to appraisal value, letter of intent to purchase, or stated value (in the case of accounts receivable, inventory and equipment).
	(2) Quantitative disclosures are not provided for OREO because there were no adjustments made to the appraisal value during the current period.
		Fair value at		Valuation Technique		Unobservable Input	Range (Weighted Average) (1)
		March 31, 2014
		(dollars in thousands)
	Impaired loans	$	990	Fair Market Value of Collateral		Adjustment to Appraisal Value	N/A (2)
	Impaired loans - other collateral (3)	1,104		Fair Market Value of Collateral		Adjustment to Stated value	0% - 100% (68%)
	OREO	6,125		Fair Market Value of Collateral		Adjustment to Appraisal Value	N/A (2)
	(1) Discount applied to appraisal value, letter of intent to purchase, or stated value (in the case of accounts receivable, inventory and equipment).
	(2) Quantitative disclosures are not provided for impaired loans collateralized by real estate and OREO because there were no adjustments made to the appraisal value during the current period.
	(3) Other collateral consists of accounts receivable, inventory and equipment.

Earnings_per_Common_Share_Tabl

Earnings per Common Share (Tables)	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Earnings Per Share	The following table sets forth the computation of basic and diluted earnings per share for the three months ended March 31, 2015 and 2014:
			Three Months Ended
			March 31,
			2015		2014
			(in thousands except per share)
	Basic EPS:
	Net income		$	24,361	$	19,844
	Less: Earnings allocated to participating securities
	Preferred shares		43		40
	Nonvested restricted shares		225		169
	Earnings allocated to common shareholders		$	24,093	$	19,635
	Weighted average common shares outstanding		56,965		51,097
	Basic earnings per common share		$	0.42	$	0.38
	Diluted EPS:
	Earnings allocated to common shareholders (1)		$	24,093	$	19,639
	Weighted average common shares outstanding		56,965		51,097
	Dilutive effect of equity awards		13		1,336
	Weighted average diluted common shares outstanding		56,978		52,433
	Diluted earnings per common share		$	0.42	$	0.37
	Potentially dilutive share options that were not included in the computation of diluted EPS because to do so would be anti-dilutive		53		83
	__________
	-1	Earnings allocated to common shareholders for basic and diluted EPS may differ under the two-class method as a result of adding common stock equivalents for options and warrants to dilutive shares outstanding, which alters the ratio used to allocate earnings to common shareholders and participating securities for the purposes of calculating diluted EPS.

Business_combinations_Details

Business combinations (Details) (USD $)	0 Months Ended	3 Months Ended
	Apr. 01, 2013	Mar. 31, 2015	Mar. 31, 2014	Apr. 01, 2013
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired	100.00%			100.00%
Business Acquisition, Pro Forma Net Income (Loss)			$21,078,000
West Coast Bancorp [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition	1-Nov-14
Business Acquisition, Cost of Acquired Entity, Purchase Price	131,900,000			131,900,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	93,400,000			93,400,000
Business Acquisition, Purchase Price Allocation, Liabilities, Deposits	-736,800,000			-736,800,000
Business Combination, Acquired Receivables, Fair Value	502,600,000			502,600,000
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets	10,900,000			10,900,000
Business Acquisition, Purchase Price Allocation, Goodwill Amount	38,600,000			38,600,000
Business Acquisition, Pro Forma Revenue			97,488,000
Business Acquisition, Pro Forma Earnings Per Share, Basic			$0.38
Business Acquisition, Pro Forma Earnings Per Share, Diluted			$0.37
Business Combination, Acquisition Related Costs		72,000	966,000
Intermountain Community Bancorp [Member]
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs		2,902,000
Compensation and employee benefits [Member] | Intermountain Community Bancorp [Member]
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs		273,000
Occupancy [Member] | Intermountain Community Bancorp [Member]
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs		499,000
Advertising and promotion [Member] | Intermountain Community Bancorp [Member]
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs		96,000
Data processing and communications [Member] | Intermountain Community Bancorp [Member]
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs		1,558,000
Legal and professional fees [Member] | Intermountain Community Bancorp [Member]
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs		385,000
Other noninterest expenses [Member] | Intermountain Community Bancorp [Member]
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs		$91,000

Securities_Securities_Availabl

Securities (Securities Available for Sale) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized cost	$1,981,977	$2,087,069
Available-for-sale Debt Securities Gross Unrealized Gain, instant	31,790	25,527
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	-6,608	-14,339
Securities available for sale	2,007,159	2,098,257
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized cost	1,093,576	1,160,378
Available-for-sale Debt Securities Gross Unrealized Gain, instant	13,765	10,219
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	-4,641	-8,210
Securities available for sale	1,102,700	1,162,387
State and Municipal Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized cost	486,969	483,578
Available-for-sale Debt Securities Gross Unrealized Gain, instant	15,434	14,432
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	-732	-1,526
Securities available for sale	501,671	496,484
U.S. Government and Government-Sponsored Enterprise Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized cost	375,230	416,919
Available-for-sale Debt Securities Gross Unrealized Gain, instant	2,551	856
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	-983	-4,069
Securities available for sale	376,798	413,706
US Government Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized cost	20,918	20,910
Available-for-sale Debt Securities Gross Unrealized Gain, instant	0	0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	-140	-411
Securities available for sale	20,778	20,499
Other Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized cost	5,284	5,284
Available-for-sale Debt Securities Gross Unrealized Gain, instant	40	20
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	-112	-123
Securities available for sale	$5,212	$5,181

Securities_Schedule_of_Contrac

Securities (Schedule of Contractual Maturities of Investment Securities Available for Sale) (Details) (USD $)	Mar. 31, 2015
In Thousands, unless otherwise specified
Available-for-sale Securities [Abstract]
Due within one year, Amortized Cost	$15,480
Due after one year through five years, Amortized Cost	404,752
Due after five years through ten years, Amortized Cost	526,230
Due after ten years, Amortized Cost	1,030,231
No stated maturity date, Amortized Cost Basis	5,284
Total investment securities available-for-sale, Amortized Cost	1,981,977
Due within one year, Fair Value	15,601
Due after one year through five years, Fair Value	406,989
Due after five years through ten years, Fair Value	534,584
Due after ten years, Fair Value	1,044,773
No stated maturity date, Fair Value	5,212
Total investment securities available-for-sale, Fair Value	$2,007,159

Securities_Carrying_Value_of_S

Securities (Carrying Value of Securities Pledged as Collateral) (Details) (USD $)	Mar. 31, 2015
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]
Carrying amount of securities pledged as collateral	$517,101
Washington and Oregon State Public Deposits [Member]
Schedule of Available-for-sale Securities [Line Items]
Carrying amount of securities pledged as collateral	323,771
Federal Reserve Bank Advances [Member]
Schedule of Available-for-sale Securities [Line Items]
Carrying amount of securities pledged as collateral	36,945
Other Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Carrying amount of securities pledged as collateral	$156,385

Securities_Summary_of_Gross_Un

Securities (Summary of Gross Unrealized Losses and Fair Value of the Investments with Unrealized Losses) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Debt Securities Gross Unrealized Gain, instant	$31,790	$25,527
Less than 12 Months Fair Value	142,162	437,414
Less than 12 Months Unrealized Losses	-863	-2,350
12 Months or More Fair Value	445,231	561,668
12 Months or More Unrealized Losses	-5,745	-11,989
Total Fair Value	587,393	999,082
Total Unrealized Losses	-6,608	-14,339
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	6,608	14,339
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Debt Securities Gross Unrealized Gain, instant	13,765	10,219
Less than 12 Months Fair Value	94,304	258,825
Less than 12 Months Unrealized Losses	-634	-1,287
12 Months or More Fair Value	213,050	279,015
12 Months or More Unrealized Losses	-4,007	-6,924
Total Fair Value	307,354	537,840
Total Unrealized Losses	-4,641	-8,211
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	4,641	8,210
State and Municipal Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Debt Securities Gross Unrealized Gain, instant	15,434	14,432
Less than 12 Months Fair Value	45,809	71,026
Less than 12 Months Unrealized Losses	-227	-543
12 Months or More Fair Value	31,597	44,148
12 Months or More Unrealized Losses	-505	-982
Total Fair Value	77,406	115,174
Total Unrealized Losses	-732	-1,525
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	732	1,526
US Government Corporations and Agencies Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Debt Securities Gross Unrealized Gain, instant	2,551	856
Less than 12 Months Fair Value	999	105,250
Less than 12 Months Unrealized Losses	-1	-518
12 Months or More Fair Value	178,013	216,221
12 Months or More Unrealized Losses	-982	-3,551
Total Fair Value	179,012	321,471
Total Unrealized Losses	-983	-4,069
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	983	4,069
US Government Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Debt Securities Gross Unrealized Gain, instant	0	0
Less than 12 Months Fair Value	1,050	0
Less than 12 Months Unrealized Losses	-1	0
12 Months or More Fair Value	19,728	19,450
12 Months or More Unrealized Losses	-139	-411
Total Fair Value	20,778	19,450
Total Unrealized Losses	-140	-411
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	140	411
Other Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Debt Securities Gross Unrealized Gain, instant	40	20
Less than 12 Months Fair Value	0	2,313
Less than 12 Months Unrealized Losses	0	-2
12 Months or More Fair Value	2,843	2,834
12 Months or More Unrealized Losses	-112	-121
Total Fair Value	2,843	5,147
Total Unrealized Losses	-112	-123
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	$112	$123

Securities_Narrative_Details

Securities (Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Gross Realized Gains (Losses), Sale Proceeds	$57.20	$6.40
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Number Of Securities In Unrealized Loss Position	77
Number Of Securities In Continuous Loss Position For Twelve Months or More	34
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Number Of Securities In Unrealized Loss Position	66
Number Of Securities In Continuous Loss Position For Twelve Months or More	32
U.S. Government and Government-Sponsored Enterprise Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Number Of Securities In Unrealized Loss Position	18
Number Of Securities In Continuous Loss Position For Twelve Months or More	14
US Government Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Number Of Securities In Unrealized Loss Position	4
Number Of Securities In Continuous Loss Position For Twelve Months or More	2
Other Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Number Of Securities In Unrealized Loss Position	1
Number Of Securities In Continuous Loss Position For Twelve Months or More	1

Securities_Securities_Summary_

Securities Securities (Summary of Gross Realized Gains and Gross Realized Losses (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Available-for-sale Securities, Gross Realized Gains	$730	$223
Available-for-sale Securities, Gross Realized Losses	-9	0
Gain (Loss) on Sale of Securities, Net	$721	$223

Loans_Narrative_Details

Loans (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
	contract
Financing Receivable, Recorded Investment [Line Items]
Loans to related parties	$12,700,000	$13,200,000
Loans and Leases Receivable, Related Parties, Additions	0
Repayments on related party loans	430,000
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	0
Loans Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	1,300,000,000	1,080,000,000
Federal Reserve Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	$47,000,000	$46,000,000

Loans_Analysis_of_Loan_Portfol

Loans (Analysis of Loan Portfolio by Major Types of Loans) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment [Line Items]
Less: Unearned income on loans	($53,867)	($59,374)
Recorded Investment	5,450,895	5,445,378
Allowance for loan losses	-70,234	-69,569	-70,571	-72,454
Loans, net	5,380,661	5,375,809
Loans held for sale	3,545	1,116
Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Less: Unearned income on loans	-53,867	-59,374
Recorded Investment	5,231,056	5,214,794
Allowance for loan losses	-53,703	-53,233
Loans, net	5,177,353	5,161,561
Loans held for sale	3,545	1,116
Loans and Leases Receivable, Gross	5,231,056	5,214,794
Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Less: Unearned income on loans	0	0
Recorded Investment	219,839	230,584
Allowance for loan losses	-16,531	-16,336
Loans, net	203,308	214,248
Loans held for sale	0	0
Loans and Leases Receivable, Gross	243,111	256,468
Acquisition Accounting Valuation Discount on Covered Loans	23,272	25,884
Commercial and Multifamily Residential Construction [Domain] | Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross	2,501	2,588
One-to-Four Family Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Consumer, Mortgage	200,340	202,564
Loans and Leases Receivable, Gross, Consumer, Construction	127,814	120,887
Allowance for loan losses	-1,364	-2,281	-1,194	-1,252
One-to-Four Family Residential [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Consumer, Mortgage	173,739	175,571
Loans and Leases Receivable, Gross, Consumer, Construction	124,017	116,866
Loans and Leases Receivable, Gross	170,307	171,764
One-to-Four Family Residential [Member] | Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Consumer, Mortgage	26,601	26,993
Loans and Leases Receivable, Gross, Consumer, Construction	3,797	4,021
Loans and Leases Receivable, Gross	31,127	31,981
Commercial and Multifamily Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable, Gross, Commercial, Mortgage	2,492,684	2,492,310
Loans Receivable, Gross, Commercial, Construction	122,118	136,764
Commercial and Multifamily Residential [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable, Gross, Commercial, Mortgage	2,374,454	2,363,541
Loans Receivable, Gross, Commercial, Construction	119,880	134,443
Commercial and Multifamily Residential [Member] | Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable, Gross, Commercial, Mortgage	118,230	128,769
Loans Receivable, Gross, Commercial, Construction	2,238	2,321
Loans and Leases Receivable, Gross	127,952	140,398
Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable, Gross, Commercial and Industrial	2,186,208	2,164,070
Commercial Portfolio Segment [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable, Gross, Commercial and Industrial	2,139,873	2,119,565
Commercial Portfolio Segment [Member] | Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable, Gross, Commercial and Industrial	46,335	44,505
Loans and Leases Receivable, Gross	52,115	50,334
Real Estate Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable Real Estate Mortgage	2,693,024	2,694,874
Real Estate Portfolio Segment [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable Real Estate Mortgage	2,548,193	2,539,112
Real Estate Portfolio Segment [Member] | Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable Real Estate Mortgage	144,831	155,762
Loans and Leases Receivable, Gross	159,079	172,379
One-to-Four Family Residential Construction [Domain] | Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross	4,026	4,353
Real Estate Construction Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable Real Estate Construction	249,932	257,651
Real Estate Construction Portfolio Segment [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable Real Estate Construction	243,897	251,309
Real Estate Construction Portfolio Segment [Member] | Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable Real Estate Construction	6,035	6,342
Loans and Leases Receivable, Gross	6,527	6,941
Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Consumer	375,598	388,157
Allowance for loan losses	-2,835	-3,180	-2,637	-2,547
Consumer Portfolio Segment [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Consumer	352,960	364,182
Loans and Leases Receivable, Gross	336,158	345,032
Consumer Portfolio Segment [Member] | Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Consumer	22,638	23,975
Loans and Leases Receivable, Gross	$25,390	$26,814

Loans_Analysis_of_Nonaccrual_L

Loans (Analysis of Nonaccrual Loans) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment Nonaccrual Loans	$31,828	$31,352
Unpaid Principal Balance Nonaccrual Loans	37,798	44,774
Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment Nonaccrual Loans	2,868	2,939
Unpaid Principal Balance Nonaccrual Loans	3,799	3,930
Secured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment Nonaccrual Loans	17,240	16,552
Unpaid Principal Balance Nonaccrual Loans	20,573	21,453
Unsecured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment Nonaccrual Loans	189	247
Unpaid Principal Balance Nonaccrual Loans	211	269
One-to-Four Family Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment Nonaccrual Loans	4,429	2,822
Unpaid Principal Balance Nonaccrual Loans	6,109	5,680
Commercial Land [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment Nonaccrual Loans	1,616	821
Unpaid Principal Balance Nonaccrual Loans	1,560	1,113
Income Property Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment Nonaccrual Loans	887	3,200
Unpaid Principal Balance Nonaccrual Loans	887	5,521
Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment Nonaccrual Loans	1,995	3,826
Unpaid Principal Balance Nonaccrual Loans	2,036	5,837
Land And Acquisition [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment Nonaccrual Loans	871	95
Unpaid Principal Balance Nonaccrual Loans	871	112
Residential Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment Nonaccrual Loans	1,263	370
Unpaid Principal Balance Nonaccrual Loans	1,263	370
Owner Occupied Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment Nonaccrual Loans	470
Unpaid Principal Balance Nonaccrual Loans	$489	$489

Loans_Analysis_of_the_Aged_Loa

Loans (Analysis of the Aged Loan Portfolio) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans	$31,828	$31,352
Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	5,171,371	5,158,985
30 - 59 Days Past Due	23,760	14,656
60 - 89 Days Past Due	3,661	8,415
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	436	1,386
Total Past Due	27,857	24,457
Nonaccrual Loans	31,828	31,352
Loans Receivable, Net	5,231,056	5,214,794
Secured Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans	17,240	16,552
Secured Loans [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	2,024,277	2,004,418
30 - 59 Days Past Due	11,910	5,137
60 - 89 Days Past Due	1,874	6,149
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	58	1,372
Total Past Due	13,842	12,658
Nonaccrual Loans	17,240	16,552
Loans Receivable, Net	2,055,359	2,033,628
Unsecured Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans	189	247
Unsecured Loans [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	78,351	79,661
30 - 59 Days Past Due	492	185
60 - 89 Days Past Due	120	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	67	0
Total Past Due	679	185
Nonaccrual Loans	189	247
Loans Receivable, Net	79,219	80,093
One-to-Four Family Residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans	4,429	2,822
One-to-Four Family Residential [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	164,962	167,197
30 - 59 Days Past Due	771	1,700
60 - 89 Days Past Due	124	45
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	21	0
Total Past Due	916	1,745
Nonaccrual Loans	4,429	2,822
Loans Receivable, Net	170,307	171,764
Commercial Land [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans	1,616	821
Commercial Land [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	186,904	187,470
30 - 59 Days Past Due	4,303	1,454
60 - 89 Days Past Due	355	34
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	264	0
Total Past Due	4,922	1,488
Nonaccrual Loans	1,616	821
Loans Receivable, Net	193,442	189,779
Income Property Multifamily [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans	887	3,200
Income Property Multifamily [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	1,305,595	1,294,982
30 - 59 Days Past Due	2,502	3,031
60 - 89 Days Past Due	560	786
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	0
Total Past Due	3,062	3,817
Nonaccrual Loans	887	3,200
Loans Receivable, Net	1,309,544	1,301,999
Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans	1,995	3,826
Owner Occupied [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	841,551	839,689
30 - 59 Days Past Due	2,206	937
60 - 89 Days Past Due	435	289
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	0
Total Past Due	2,641	1,226
Nonaccrual Loans	1,995	3,826
Loans Receivable, Net	846,187	844,741
Land And Acquisition [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans	871	95
Land And Acquisition [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	15,860	15,462
30 - 59 Days Past Due	67	953
60 - 89 Days Past Due	0	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	0
Total Past Due	67	953
Nonaccrual Loans	871	95
Loans Receivable, Net	16,798	16,510
Residential Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans	1,263	370
Residential Construction [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	104,378	97,821
30 - 59 Days Past Due	0	326
60 - 89 Days Past Due	0	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	4	4
Total Past Due	4	330
Nonaccrual Loans	1,263	370
Loans Receivable, Net	105,645	98,521
Income Property Multifamily Construction [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	62,958	73,783
30 - 59 Days Past Due	0	0
60 - 89 Days Past Due	0	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	0
Total Past Due	0	0
Nonaccrual Loans	0	0
Loans Receivable, Net	62,958	73,783
Owner Occupied Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans	470
Owner Occupied Construction [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	54,969	57,470
30 - 59 Days Past Due	0	0
60 - 89 Days Past Due	0	994
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	0
Total Past Due	0	994
Nonaccrual Loans	470	480
Loans Receivable, Net	55,439	58,944
Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans	2,868	2,939
Consumer Portfolio Segment [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	331,566	341,032
30 - 59 Days Past Due	1,509	933
60 - 89 Days Past Due	193	118
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	22	10
Total Past Due	1,724	1,061
Nonaccrual Loans	2,868	2,939
Loans Receivable, Net	$336,158	$345,032

Loans_Analysis_of_Impaired_Loa

Loans (Analysis of Impaired Loans) (Details) (Loans, Excluding Purchased Credit Impaired Loans [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	$5,203,960		$5,186,695
Recorded Investment of Loans Individually Measured for Specific Impairment	27,096		28,099
Recorded Investment	25,893		26,883
Unpaid Principal Balance	31,634		38,433
Related Allowance	230		241
Average Recorded Investment Impaired Loans	27,596	26,538
Interest Recognized on Impaired Loans	267	336
Secured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	2,044,486		2,023,104
Recorded Investment of Loans Individually Measured for Specific Impairment	10,873		10,524
Recorded Investment	96		99
Unpaid Principal Balance	96		99
Related Allowance	24		25
Average Recorded Investment Impaired Loans	10,698	6,232
Interest Recognized on Impaired Loans	7	17
Unsecured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	79,219		80,091
Recorded Investment of Loans Individually Measured for Specific Impairment	0		2
Recorded Investment	0		2
Unpaid Principal Balance	0		2
Related Allowance	0		2
Average Recorded Investment Impaired Loans	1	31
Interest Recognized on Impaired Loans	0	0
One-to-Four Family Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	166,129		169,619
Recorded Investment of Loans Individually Measured for Specific Impairment	4,178		2,145
Recorded Investment	420		424
Unpaid Principal Balance	461		465
Related Allowance	115		120
Average Recorded Investment Impaired Loans	3,162	1,856
Interest Recognized on Impaired Loans	13	13
Commercial Land [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	192,972		189,779
Recorded Investment of Loans Individually Measured for Specific Impairment	470		0
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Related Allowance	0		0
Average Recorded Investment Impaired Loans	235	111
Interest Recognized on Impaired Loans	0	0
Income Property Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	1,307,556		1,295,650
Recorded Investment of Loans Individually Measured for Specific Impairment	1,988		6,349
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Related Allowance	0		0
Average Recorded Investment Impaired Loans	4,168	6,436
Interest Recognized on Impaired Loans	10	62
Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	839,157		835,895
Recorded Investment of Loans Individually Measured for Specific Impairment	7,030		8,846
Recorded Investment	578		582
Unpaid Principal Balance	578		582
Related Allowance	24		27
Average Recorded Investment Impaired Loans	7,938	10,140
Interest Recognized on Impaired Loans	234	241
Land And Acquisition [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	15,818		16,401
Recorded Investment of Loans Individually Measured for Specific Impairment	980		109
Recorded Investment	109		109
Unpaid Principal Balance	108		109
Related Allowance	67		67
Average Recorded Investment Impaired Loans	544	1,569
Interest Recognized on Impaired Loans	1	1
Residential Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	104,752		98,521
Recorded Investment of Loans Individually Measured for Specific Impairment	893		0
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Related Allowance	0		0
Average Recorded Investment Impaired Loans	446	0
Interest Recognized on Impaired Loans	0	0
Income Property Multifamily Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	62,958		73,783
Recorded Investment of Loans Individually Measured for Specific Impairment	0		0
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Related Allowance	0		0
Owner Occupied Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	55,439		58,944
Recorded Investment of Loans Individually Measured for Specific Impairment	0		0
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Related Allowance	0		0
Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	335,474		344,908
Recorded Investment of Loans Individually Measured for Specific Impairment	684		124
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Related Allowance	0		0
Average Recorded Investment Impaired Loans	404	163
Interest Recognized on Impaired Loans	2	2
Impaired Loans With Recorded Allowance [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	1,203		1,216
Unpaid Principal Balance	1,243		1,257
Impaired Loans Without Recorded Allowance [Member] | Secured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	10,777		10,425
Unpaid Principal Balance	12,986		12,410
Impaired Loans Without Recorded Allowance [Member] | Unsecured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Impaired Loans Without Recorded Allowance [Member] | One-to-Four Family Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	3,758		1,721
Unpaid Principal Balance	4,220		2,370
Impaired Loans Without Recorded Allowance [Member] | Commercial Land [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	470		0
Unpaid Principal Balance	470		0
Impaired Loans Without Recorded Allowance [Member] | Income Property Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	1,988		6,349
Unpaid Principal Balance	2,355		10,720
Impaired Loans Without Recorded Allowance [Member] | Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	6,452		8,264
Unpaid Principal Balance	8,944		12,732
Impaired Loans Without Recorded Allowance [Member] | Land And Acquisition [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	871		0
Unpaid Principal Balance	871		0
Impaired Loans Without Recorded Allowance [Member] | Residential Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	893		0
Unpaid Principal Balance	893		0
Impaired Loans Without Recorded Allowance [Member] | Income Property Multifamily Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Impaired Loans Without Recorded Allowance [Member] | Owner Occupied Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Impaired Loans Without Recorded Allowance [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	684		124
Unpaid Principal Balance	$895		$201

Loans_Loans_Analysis_of_Troubl

Loans Loans (Analysis of Troubled Debt Restructurings) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
	Modifications	Modifications
Financing Receivable, Modifications [Line Items]
Financing Receivable Modifications Additional Commitment To Lend	0		$0
Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR Modifications	0	5
Pre-Modification Outstanding Recorded Investment		1,183
Post-Modification Outstanding Recorded Investment		1,166
Loans, Excluding Purchased Credit Impaired Loans [Member] | Secured Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR Modifications		2
Pre-Modification Outstanding Recorded Investment		546
Post-Modification Outstanding Recorded Investment		546
Loans, Excluding Purchased Credit Impaired Loans [Member] | One-to-Four Family Residential [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR Modifications		2
Pre-Modification Outstanding Recorded Investment		494
Post-Modification Outstanding Recorded Investment		494
Loans, Excluding Purchased Credit Impaired Loans [Member] | Income Property Multifamily [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR Modifications		1
Pre-Modification Outstanding Recorded Investment		143
Post-Modification Outstanding Recorded Investment		$126

Loans_Loans_Analysis_of_Purcha

Loans Loans (Analysis of Purchased Credit Impaired Loans - Accretable Yield Rollforward) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
Loans, Analysis of Purchased Credit Impaired Loans, Accretable Yield Rollforward [Abstract]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield	$68,726	$101,543	$73,849	$103,907
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Accretion	6,319	10,569
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Disposals of Loans	1,093	2,826
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Reclassifications from Nonaccretable Difference	$2,289	$11,031

Allowance_for_Loan_and_Lease_L2

Allowance for Loan and Lease Losses and Unfunded Commitments and Letters of Credit (Narrative) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for loan and lease losses	$1,209	[1]	$1,922	[1]
Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of unallocated loan amount	5.00%
[1]	{F|ahBzfndlYmZpbGluZ3MtaHJkcmoLEgZYTUxEb2MiXlhCUkxEb2NHZW5JbmZvOjNlZWQyMzNmYzU4NTQ3YjE4YmZiNDE3NjBhNjc1ZWQ4fFRleHRTZWxlY3Rpb246QTFEODJCNjcwRTEwQ0JFQ0Q1OEYwNERBMjg2MDZBQzAM}

Allowance_for_Loan_and_Lease_L3

Allowance for Loan and Lease Losses and Unfunded Commitments and Letters of Credit (Allowance for Loan and Lease Losses) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$69,569		$72,454
Charged-offs	-6,425		-6,463
Recoveries	5,881		2,658
Provision for loan and lease losses	1,209	[1]	1,922	[1]
Ending balance	70,234		70,571
Specific Reserve	230		1,793
General Allocation	70,004		68,778
Secured Loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	25,923		31,027
Charged-offs	-1,386		-198
Recoveries	512		448
Provision for loan and lease losses	712		-2,476
Ending balance	25,761		28,801
Specific Reserve	24		1,521
General Allocation	25,737		27,280
Unsecured Loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	927		696
Charged-offs	-40		-35
Recoveries	106		42
Provision for loan and lease losses	19		43
Ending balance	1,012		746
Specific Reserve	0		27
General Allocation	1,012		719
One-to-Four Family Residential [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,281		1,252
Charged-offs	-8		-207
Recoveries	12		28
Provision for loan and lease losses	-921		121
Ending balance	1,364		1,194
Specific Reserve	115		133
General Allocation	1,249		1,061
Commercial Land [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	799		489
Charged-offs	0		0
Recoveries	0		17
Provision for loan and lease losses	28		73
Ending balance	827		579
Specific Reserve	0		0
General Allocation	827		579
Income Property Multifamily [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	9,159		9,234
Charged-offs	0		0
Recoveries	3,252		13
Provision for loan and lease losses	-3,971		860
Ending balance	8,440		10,107
Specific Reserve	0		0
General Allocation	8,440		10,107
Owner Occupied [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	5,007		3,605
Charged-offs	0		-1,023
Recoveries	9		9
Provision for loan and lease losses	596		1,969
Ending balance	5,612		4,560
Specific Reserve	24		38
General Allocation	5,588		4,522
Land And Acquisition [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,197		610
Charged-offs	0		0
Recoveries	2		39
Provision for loan and lease losses	-173		-69
Ending balance	1,026		580
Specific Reserve	67		71
General Allocation	959		509
Residential Construction [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,860		822
Charged-offs	0		0
Recoveries	26		3
Provision for loan and lease losses	-96		-129
Ending balance	1,790		696
Specific Reserve	0		0
General Allocation	1,790		696
Income Property Multifamily Construction [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	622		285
Charged-offs	0		0
Recoveries	3		0
Provision for loan and lease losses	202		35
Ending balance	827		320
Specific Reserve	0		0
General Allocation	827		320
Owner Occupied Construction [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	434		58
Charged-offs	0		0
Recoveries	0		0
Provision for loan and lease losses	65		96
Ending balance	499		154
Specific Reserve	0		0
General Allocation	499		154
Consumer Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	3,180		2,547
Charged-offs	-891		-727
Recoveries	273		253
Provision for loan and lease losses	273		564
Ending balance	2,835		2,637
Specific Reserve	0		3
General Allocation	2,835		2,634
Purchased Credit Impaired Loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	16,336		20,174
Charged-offs	-4,100		-4,273
Recoveries	1,686		1,806
Provision for loan and lease losses	2,609		2,422
Ending balance	16,531		20,129
Specific Reserve	0		0
General Allocation	16,531		20,129
Unallocated Financing Receivables [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,844		1,655
Charged-offs	0		0
Recoveries	0		0
Provision for loan and lease losses	1,866		-1,587
Ending balance	3,710		68
Specific Reserve	0		0
General Allocation	$3,710		$68
[1]	{F|ahBzfndlYmZpbGluZ3MtaHJkcmoLEgZYTUxEb2MiXlhCUkxEb2NHZW5JbmZvOjNlZWQyMzNmYzU4NTQ3YjE4YmZiNDE3NjBhNjc1ZWQ4fFRleHRTZWxlY3Rpb246QTFEODJCNjcwRTEwQ0JFQ0Q1OEYwNERBMjg2MDZBQzAM}

Allowance_for_Loan_and_Lease_L4

Allowance for Loan and Lease Losses and Unfunded Commitments and Letters of Credit (Changes in the Allowance for Unfunded Commitments and Letters of Credit) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Allowance For Loan And Lease Losses And Unfunded Loan Commitments And Letters Of Credit
Beginning balance	$2,655	$2,505
Allowance for Loan and Lease Losses, Net Changes In Unfunded Commitments and Letters Of Credit Allowance	0	-50
Ending balance	$2,655	$2,455

Allowance_for_Loan_and_Lease_L5

Allowance for Loan and Lease Losses and Unfunded Commitments and Letters of Credit (Analysis of Credit Quality of the Loan Portfolio) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance	$70,234	$69,569	$70,571	$72,454
Loans, net	5,380,661	5,375,809
Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	5,231,056	5,214,794
Loans and Leases Receivable, Allowance	53,703	53,233
Loans, net	5,177,353	5,161,561
Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	243,111	256,468
Acquisition Accounting Valuation Discount on Purchased Credit Impaired Loans	23,272
Loans and Leases Receivable, Allowance	16,531	16,336
Loans, net	203,308	214,248
Pass [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	5,122,539	5,086,653
Special Mention [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	30,254	34,967
Substandard [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	78,263	93,174
Substandard [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	33,945	36,486
Doubtful [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Doubtful [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0
Unlikely to be Collected Financing Receivable [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Unlikely to be Collected Financing Receivable [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Secured Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance	25,761	25,923	28,801	31,027
Secured Loans [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	2,055,359	2,033,628
Secured Loans [Member] | Pass [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	1,995,680	1,963,210
Secured Loans [Member] | Special Mention [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	19,210	15,790
Secured Loans [Member] | Substandard [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	40,469	54,628
Secured Loans [Member] | Substandard [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	9,060
Secured Loans [Member] | Doubtful [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Secured Loans [Member] | Doubtful [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Secured Loans [Member] | Unlikely to be Collected Financing Receivable [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Unsecured Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance	1,012	927	746	696
Unsecured Loans [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	79,219	80,093
Unsecured Loans [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	2,096	2,247
Unsecured Loans [Member] | Pass [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	78,498	79,534
Unsecured Loans [Member] | Pass [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	2,057
Unsecured Loans [Member] | Special Mention [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Unsecured Loans [Member] | Special Mention [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Unsecured Loans [Member] | Substandard [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	721	559
Unsecured Loans [Member] | Substandard [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	39
Unsecured Loans [Member] | Doubtful [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Unsecured Loans [Member] | Doubtful [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Unsecured Loans [Member] | Unlikely to be Collected Financing Receivable [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Unsecured Loans [Member] | Unlikely to be Collected Financing Receivable [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
One-to-Four Family Residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance	1,364	2,281	1,194	1,252
One-to-Four Family Residential [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	170,307	171,764
One-to-Four Family Residential [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	31,127	31,981
One-to-Four Family Residential [Member] | Pass [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	162,448	163,914
One-to-Four Family Residential [Member] | Pass [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	27,881
One-to-Four Family Residential [Member] | Special Mention [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	1,465	55
One-to-Four Family Residential [Member] | Substandard [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	6,394	7,795
One-to-Four Family Residential [Member] | Doubtful [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
One-to-Four Family Residential [Member] | Doubtful [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		0
One-to-Four Family Residential [Member] | Unlikely to be Collected Financing Receivable [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Commercial Land [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance	827	799	579	489
Commercial Land [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	193,442	189,779
Commercial Land [Member] | Pass [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	187,519	183,701
Commercial Land [Member] | Special Mention [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	3,459	4,217
Commercial Land [Member] | Special Mention [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0
Commercial Land [Member] | Substandard [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	2,464	1,861
Commercial Land [Member] | Substandard [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	1,668
Commercial Land [Member] | Doubtful [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Commercial Land [Member] | Unlikely to be Collected Financing Receivable [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Commercial Land [Member] | Unlikely to be Collected Financing Receivable [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0
Income Property Multifamily [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance	8,440	9,159	10,107	9,234
Income Property Multifamily [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	1,309,544	1,301,999
Income Property Multifamily [Member] | Pass [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	1,301,779	1,287,729
Income Property Multifamily [Member] | Pass [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	45,298
Income Property Multifamily [Member] | Special Mention [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	3,517	5,885
Income Property Multifamily [Member] | Special Mention [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0
Income Property Multifamily [Member] | Substandard [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	4,248	8,385
Income Property Multifamily [Member] | Substandard [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	12,031	7,186
Income Property Multifamily [Member] | Doubtful [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Income Property Multifamily [Member] | Doubtful [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		0
Income Property Multifamily [Member] | Unlikely to be Collected Financing Receivable [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance	5,612	5,007	4,560	3,605
Owner Occupied [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	846,187	844,741
Owner Occupied [Member] | Pass [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	828,244	825,694
Owner Occupied [Member] | Special Mention [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	1,757	7,876
Owner Occupied [Member] | Special Mention [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		346
Owner Occupied [Member] | Substandard [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	16,186	11,171
Owner Occupied [Member] | Doubtful [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Owner Occupied [Member] | Doubtful [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		0
Owner Occupied [Member] | Unlikely to be Collected Financing Receivable [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Owner Occupied [Member] | Unlikely to be Collected Financing Receivable [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		0
Land And Acquisition [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance	1,026	1,197	580	610
Land And Acquisition [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	16,798	16,510
Land And Acquisition [Member] | Pass [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	16,180	15,307
Land And Acquisition [Member] | Special Mention [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	166	167
Land And Acquisition [Member] | Special Mention [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		0
Land And Acquisition [Member] | Substandard [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	452	1,036
Land And Acquisition [Member] | Substandard [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	894
Land And Acquisition [Member] | Doubtful [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Land And Acquisition [Member] | Doubtful [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		0
Land And Acquisition [Member] | Unlikely to be Collected Financing Receivable [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Land And Acquisition [Member] | Unlikely to be Collected Financing Receivable [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0
Residential Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance	1,790	1,860	696	822
Residential Construction [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	105,645	98,521
Residential Construction [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		1,845
Residential Construction [Member] | Pass [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	103,257	96,031
Residential Construction [Member] | Pass [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	732	741
Residential Construction [Member] | Special Mention [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	680	909
Residential Construction [Member] | Special Mention [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0
Residential Construction [Member] | Substandard [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	1,708	1,581
Residential Construction [Member] | Substandard [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		1,104
Residential Construction [Member] | Doubtful [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Residential Construction [Member] | Doubtful [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		0
Residential Construction [Member] | Unlikely to be Collected Financing Receivable [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Residential Construction [Member] | Unlikely to be Collected Financing Receivable [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		0
Income Property Multifamily Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance	827	622	320	285
Income Property Multifamily Construction [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	62,958	73,783
Income Property Multifamily Construction [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		1,662
Income Property Multifamily Construction [Member] | Pass [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	62,958	73,783
Income Property Multifamily Construction [Member] | Special Mention [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Income Property Multifamily Construction [Member] | Special Mention [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0
Income Property Multifamily Construction [Member] | Substandard [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Income Property Multifamily Construction [Member] | Substandard [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	224
Income Property Multifamily Construction [Member] | Doubtful [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Income Property Multifamily Construction [Member] | Unlikely to be Collected Financing Receivable [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Income Property Multifamily Construction [Member] | Unlikely to be Collected Financing Receivable [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		0
Owner Occupied Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance	499	434	154	58
Owner Occupied Construction [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	55,439	58,944
Owner Occupied Construction [Member] | Pass [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	54,563	58,055
Owner Occupied Construction [Member] | Special Mention [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Owner Occupied Construction [Member] | Special Mention [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Owner Occupied Construction [Member] | Substandard [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	876	889
Owner Occupied Construction [Member] | Substandard [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		0
Owner Occupied Construction [Member] | Doubtful [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Owner Occupied Construction [Member] | Unlikely to be Collected Financing Receivable [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Owner Occupied Construction [Member] | Unlikely to be Collected Financing Receivable [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance	2,835	3,180	2,637	2,547
Consumer Portfolio Segment [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	336,158	345,032
Consumer Portfolio Segment [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	25,390	26,814
Consumer Portfolio Segment [Member] | Pass [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	331,413	339,695
Consumer Portfolio Segment [Member] | Pass [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		24,037
Consumer Portfolio Segment [Member] | Special Mention [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	68
Consumer Portfolio Segment [Member] | Substandard [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	4,745	5,269
Consumer Portfolio Segment [Member] | Substandard [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	1,959	2,777
Consumer Portfolio Segment [Member] | Doubtful [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Consumer Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member] | Loans, Excluding Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	0	0
Consumer Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member] | Purchased Credit Impaired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		$0

Other_Real_Estate_Owned_Summar

Other Real Estate Owned (Summary of Other Real Estate Owned) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Other Real Estate Owned [Line Items]
Balance, beginning of period	$22,190,000	$35,927,000
Transfers in	4,692,000	5,751,000
Valuation adjustments	-197,000	-1,580,000
Proceeds from Sale of OREO Property	5,122,000	11,205,000
Gain (loss) on sale of OREO	1,736,000	1,659,000
Total OREO, end of period	23,299,000	30,552,000
Mortgage Loans in Process of Foreclosure, Amount	2,700,000
One-to-Four Family Residential [Member]
Other Real Estate Owned [Line Items]
Total OREO, end of period	$2,100,000

Covered_Assets_and_FDIC_Losssh2

Covered Assets and FDIC Loss-sharing Asset (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Amount of Estimated Clawback Liability	$4,199,000
Payment Of Clawback If Losses Less Than Stated Levels, Period After Acquisition	10 years 45 days
Federal deposit insurance corporation loss-sharing indemnified assets	10,600,000
Federal deposit insurance corporation loss-sharing indemnified assets receivable	$4,000,000
Maximum [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Loss Sharing Agreement Effective Years	10 years
Loss Recovery Provision Effective Years	10 years
Minimum [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Loss Sharing Agreement Effective Years	5 years
Loss Recovery Provision Effective Years	8 years
Covered Loans [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Percentage of loss shared by FDIC	80.00%
FDIC Percentage Of Loss Recoveries	80.00%
Percentage of loss shared by FDIC When Loss Share Thresholds Met	95.00%
Percentage Of Loss Recoveries Shared By FDIC When Loss Share Thresholds Met	95.00%

Covered_Assets_and_FDIC_Losssh3

Covered Assets and FDIC Loss-sharing Asset (FDIC Loss-sharing Asset) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Balance at beginning of period	$15,174	$39,846
Cash received from the FDIC	-659	1,678
FDIC reimbursable losses, net	-21	132
Amortization, net	-2,294	-6,452
Impairment	1,532	1,938
Sale of other real estate	-420	-756
Write-downs of other real estate	1,071	516
Other	261	-65
Balance at end of period	14,644	36,837
Amount of Estimated Clawback Liability	4,199
Non-Single Family Covered Assets	160,668
Single Family Covered Assets	45,186
Columbia River Bank [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Balance at end of period	2,124
Amount of Estimated Clawback Liability	4,063
Non-Single Family Covered Assets	107,135
Single Family Covered Assets	9,994
American Marine Bank [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Balance at end of period	4,824
Amount of Estimated Clawback Liability	136
Non-Single Family Covered Assets	16,914
Single Family Covered Assets	26,391
Summit Bank [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Balance at end of period	4,162
Amount of Estimated Clawback Liability	0
Non-Single Family Covered Assets	13,856
Single Family Covered Assets	6,322
First Heritage Bank [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Balance at end of period	3,534
Amount of Estimated Clawback Liability	0
Non-Single Family Covered Assets	22,763
Single Family Covered Assets	$2,479

Goodwill_and_Intangible_Assets2

Goodwill and Intangible Assets (Schedule of Goodwill and Intangible Assets) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
Goodwill and Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets (Excluding Goodwill)	$919	$919
Other intangible assets, net	28,642	24,273	30,459
Goodwill and Intangible Assets [Roll Forward]
Total goodwill, beginning of period	382,537
Total goodwill, end of period	382,537	343,952
CDI current period amortization	-1,817	-1,580
Total goodwill and intangible assets, end of period	411,179	368,225
Core Deposits [Member]
Goodwill and Intangible Assets [Line Items]
Estimated life of CDI, in years	10 years
Goodwill and Intangible Assets [Roll Forward]
Gross core deposit intangible balance, beginning of period			58,598	47,698
Accumulated amortization at beginning of period			-29,058	-22,765
Core deposit intangible, net, beginning of period	29,540	24,933
CDI current period amortization	-1,817	-1,579
Total core deposit intangible, end of period	$27,723	$23,354

Goodwill_and_Intangible_Assets3

Goodwill and Intangible Assets (Estimated Future Amortization Expense of Core Deposit Intangibles) (Details) (USD $)	Mar. 31, 2015
In Thousands, unless otherwise specified
Future Amortization Expense For Core Deposit Intangibles
2015	$5,065
2016	5,945
2017	4,913
2018	3,855
2019	$2,951

Derivatives_and_Balance_Sheet_2

Derivatives and Balance Sheet Offsetting (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	($5,000)	$0
Not Designated as Hedging Instrument [Member] | Interest Rate Contracts [Member]
Derivative [Line Items]
Derivative, Notional Amount	222,900,000		215,600,000
Not Designated as Hedging Instrument [Member] | Other Assets [Member] | Interest Rate Contracts [Member]
Derivative [Line Items]
Fair value of asset derivative instruments	14,244,000		11,800,000
Not Designated as Hedging Instrument [Member] | Other Liabilities [Member] | Interest Rate Contracts [Member]
Derivative [Line Items]
Fair value of liability derivative instruments	$14,300,000		$11,851,000

Derivatives_and_Balance_Sheet_3

Derivatives and Balance Sheet Offsetting Balance Sheet Offsetting (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Balance Sheet Offsetting [Line Items]
Repurchase agreements, amounts offset in balance sheet	$0	$0
Repurchase agreements, net amount presented in statement of financial position	96,852	105,080
Securities Sold under Agreements to Repurchase, Collateral, Right to Reclaim Securities	-96,852	-105,080
Securities sold under agreements to repurchase, amount not offset	0	0
Interest Rate Contracts [Member]
Balance Sheet Offsetting [Line Items]
Derivative Assets, Gross Amounts Offset in the Balance Sheets	0	0
Derivative Asset	14,244	11,800
Derivative, Collateral, Obligation to Return Securities	0	0
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	14,244	11,800
Derivative Liability, Gross Amounts Offset in Balance Sheets	0	0
Derivative Liability	14,300	11,851
Derivative, Collateral, Right to Reclaim Securities	-14,300	-11,851
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	0	0
Not Designated as Hedging Instrument [Member] | Interest Rate Contracts [Member] | Other Assets [Member]
Balance Sheet Offsetting [Line Items]
Fair value of asset derivative instruments	14,244	11,800
Not Designated as Hedging Instrument [Member] | Interest Rate Contracts [Member] | Other Liabilities [Member]
Balance Sheet Offsetting [Line Items]
Fair value of liability derivative instruments	14,300	11,851
Available-for-sale Securities [Member]
Balance Sheet Offsetting [Line Items]
Securities Sold under Agreements to Repurchase, Gross	$96,852	$105,080

Shareholders_Equity_Details

Shareholders' Equity (Details) (USD $)	0 Months Ended
	Jan. 29, 2015	Apr. 22, 2015	Apr. 01, 2013
Subsequent Event [Line Items]
Declared quarterly cash dividend	$0.16
Special Dividends Payable, Amount Per Share	$0.14
Dividend Declared [Member]
Subsequent Event [Line Items]
Declared quarterly cash dividend		$0.18
Special Dividends Payable, Amount Per Share		$0.16
Preferred Stock [Member]
Subsequent Event [Line Items]
Stock Issued During Period, Shares, New Issues			8,782

Shareholders_Equity_Narrative_

Shareholders' Equity Narrative (Details)	Mar. 31, 2015
Shareholders' Equity [Abstract]
Preferred Stock Converted Into Common Stock, Shares	102,363

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Income (Changes in AOCI by Component) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$5,621	[1]	($12,044)	[1]
Other comprehensive income (loss) before reclassifications	9,096	[1]	7,119	[1]
Amounts reclassified from accumulated other comprehensive income (loss) (2)	-431	[1],[2]	-118	[1],[2]
Net current-period other comprehensive income (loss)	8,665	[1]	7,001	[1]
Ending balance	14,286	[1]	-5,043	[1]
Unrealized Gains and Losses on Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	7,462	[1]	-10,108	[1]
Other comprehensive income (loss) before reclassifications	9,376	[1]	7,119	[1]
Amounts reclassified from accumulated other comprehensive income (loss) (2)	-459	[1],[2]	-142	[1],[2]
Net current-period other comprehensive income (loss)	8,917	[1]	6,977	[1]
Ending balance	16,379	[1]	-3,131	[1]
Unrealized Gains and Losses on Pension Plan Liability [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	-1,841	[1]	-1,936	[1]
Other comprehensive income (loss) before reclassifications	-280	[1]	0	[1]
Amounts reclassified from accumulated other comprehensive income (loss) (2)	28	[1],[2]	24	[1],[2]
Net current-period other comprehensive income (loss)	-252	[1]	24	[1]
Ending balance	($2,093)	[1]	($1,912)	[1]
[1]	All amounts are net of tax. Amounts in parenthesis indicate debits.
[2]	See following table for details about these reclassifications.

Accumulated_Other_Comprehensiv3

Accumulated Other Comprehensive Income (Reclassification out of AOCI) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Investment securities gains, net	$721	$223
Compensation and employee benefits	39,100	31,338
Total before tax	35,188	28,640
Income tax provision	-10,827	-8,796
Net of tax	24,361	19,844
Reclassification out of Accumulated Other Comprehensive Income [Member] | Unrealized Gains and Losses on Available-for-Sale Securities [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Investment securities gains, net	721	223
Total before tax	721	223
Income tax provision	-262	-81
Net of tax	459	142
Reclassification out of Accumulated Other Comprehensive Income [Member] | Unrealized Gains and Losses on Pension Plan Liability [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Compensation and employee benefits	-44	-37
Total before tax	-44	-37
Income tax provision	16	13
Net of tax	($28)	($24)

Fair_Value_Accounting_and_Meas2

Fair Value Accounting and Measurement (Financial Assets And Liabilities Accounted for Fair Value On Recurring Basis) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	$2,007,159	$2,098,257
Fair Value, Level 2 to level 1 Transfers, Amount	0
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	2,007,159	2,098,257
Other assets (Interest rate contracts)	14,244	11,800
Other liabilities (Interest rate contracts)	14,300	11,851
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	20,778	20,499
Other assets (Interest rate contracts)	0	0
Other liabilities (Interest rate contracts)	0	0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,986,381	2,077,758
Other assets (Interest rate contracts)	14,244	11,800
Other liabilities (Interest rate contracts)	14,300	11,851
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Other assets (Interest rate contracts)	0	0
Other liabilities (Interest rate contracts)	0	0
U.S. Government Agency and Sponsored Enterprise Mortgage-Back Securities and Collateralized Mortgage Obligations [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,102,700	1,162,387
U.S. Government Agency and Sponsored Enterprise Mortgage-Back Securities and Collateralized Mortgage Obligations [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
U.S. Government Agency and Sponsored Enterprise Mortgage-Back Securities and Collateralized Mortgage Obligations [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,102,700	1,162,387
U.S. Government Agency and Sponsored Enterprise Mortgage-Back Securities and Collateralized Mortgage Obligations [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
State and Municipal Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	501,671	496,484
State and Municipal Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
State and Municipal Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	501,671	496,484
State and Municipal Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
U.S. Government Agency [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	376,798	413,706
U.S. Government Agency [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
U.S. Government Agency [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	376,798	413,706
U.S. Government Agency [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
US Government Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	20,778	20,499
US Government Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	20,778	20,499
US Government Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
US Government Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Other Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	5,212	5,181
Other Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Other Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	5,212	5,181
Other Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	$0	$0

Fair_Value_Accounting_and_Meas3

Fair Value Accounting and Measurement (Financial Assets Accounted For Fair Value On Nonrecurring Basis) (Details) (Fair Value, Measurements, Nonrecurring [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans		$2,094
Fair Value, Option, Changes in Fair Value, Gain (Loss)	-197	-2,690
OREO	1,429	6,125
Assets, Fair Value Disclosure	1,429	8,219
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans		0
OREO	0	0
Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans		0
OREO	0	0
Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans		2,094
OREO	1,429	6,125
Assets, Fair Value Disclosure	1,429	8,219
Impaired Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Option, Changes in Fair Value, Gain (Loss)		-1,387
Other Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Option, Changes in Fair Value, Gain (Loss)	($197)	($1,303)

Fair_Value_Accounting_and_Meas4

Fair Value Accounting and Measurement (Quantitative Information About Level 3 Fair Value Measurements) (Details) (Fair Value, Measurements, Nonrecurring [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans			2,094
OREO	1,429		6,125
Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans			2,094
OREO	1,429		6,125
Real Estate Collateral [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans			990
Other Collateral [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans			1,104
Other Collateral [Member] | Market Approach Valuation Technique [Member] | Impaired Loans [Member] | Minimum [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	0.00%	[1],[2]	0.00%	[1]
Other Collateral [Member] | Market Approach Valuation Technique [Member] | Impaired Loans [Member] | Maximum [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	0.00%	[1],[2]	100.00%	[1]
Other Collateral [Member] | Market Approach Valuation Technique [Member] | Impaired Loans [Member] | Weighted Average [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	0.00%	[1],[2]	68.00%	[1],[2]
[1]	Discount applied to appraisal value, letter of intent to purchase, or stated value (in the case of accounts receivable and inventory).
[2]	Other collateral consists of accounts receivable and inventory.

Fair_Value_Accounting_and_Meas5

Fair Value Accounting and Measurement (Carrying Amounts and Estimated Fair Values of Selected Financial Instruments) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Assets
Interest-earning deposits with banks	$71,575	$16,949
Securities available for sale	2,007,159	2,098,257
Carrying (Reported) Amount, Fair Value Disclosure [Member]
Assets
Cash and due from banks	177,026	171,221
Interest-earning deposits with banks	71,575	16,949
Securities available for sale	2,007,159	2,098,257
FHLB stock	33,004	33,365
Loans held for sale	3,545	1,116
Loans	5,380,661	5,375,809
FDIC loss-sharing asset	14,644	15,174
Interest rate contracts	14,244	11,800
Liabilities
Deposits	7,074,965	6,924,722
FHLB Advances	36,559	216,568
Repurchase agreements	96,852	105,080
Interest rate contracts	14,300	11,851
Estimate of Fair Value, Fair Value Disclosure [Member]
Assets
Cash and due from banks	177,026	171,221
Interest-earning deposits with banks	71,575	16,949
Securities available for sale	2,007,159	2,098,257
FHLB stock	33,004	33,365
Loans held for sale	3,545	1,116
Loans	5,540,202	5,516,286
FDIC loss-sharing asset	4,918	4,054
Interest rate contracts	14,244	11,800
Liabilities
Deposits	7,069,844	6,921,804
FHLB Advances	37,413	217,296
Repurchase agreements	97,868	106,171
Interest rate contracts	14,300	11,851
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Assets
Cash and due from banks	177,026	171,221
Interest-earning deposits with banks	71,575	16,949
Securities available for sale	20,778	20,499
FHLB stock	0	0
Loans held for sale	0	0
Loans	0	0
FDIC loss-sharing asset	0	0
Interest rate contracts	0	0
Liabilities
Deposits	6,577,549	6,416,017
FHLB Advances	0	0
Repurchase agreements	0	0
Interest rate contracts	0	0
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Assets
Cash and due from banks	0	0
Interest-earning deposits with banks	0	0
Securities available for sale	1,986,381	2,077,758
FHLB stock	33,004	33,365
Loans held for sale	3,545	1,116
Loans	0	0
FDIC loss-sharing asset	0	0
Interest rate contracts	14,244	11,800
Liabilities
Deposits	492,295	505,787
FHLB Advances	37,413	217,296
Repurchase agreements	97,868	106,171
Interest rate contracts	14,300	11,851
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Assets
Cash and due from banks	0	0
Interest-earning deposits with banks	0	0
Securities available for sale	0	0
FHLB stock	0	0
Loans held for sale	0	0
Loans	5,540,202	5,516,286
FDIC loss-sharing asset	4,918	4,054
Interest rate contracts	0	0
Liabilities
Deposits	0	0
FHLB Advances	0	0
Repurchase agreements	0	0
Interest rate contracts	$0	$0

Earnings_per_Common_Share_Deta

Earnings per Common Share (Details) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Earnings Per Share [Abstract]
Net Income	$24,361		$19,844
Earnings allocated to participating securities - nonvested restricted shares	225		169
Earnings allocated to participating securities - preferred shares	43		40
Earnings allocated to common shareholders, Basic	24,093		19,635
Weighted average common shares outstanding	56,965		51,097
Basic earnings per common share	$0.42		$0.38
Dilutive effect of equity awards and warrants	13		1,336
Earnings allocated to common shareholders, Diluted	$24,093	[1]	$19,639	[1]
Weighted average diluted common shares outstanding	56,978		52,433
Diluted earnings per common share	$0.42		$0.37
Potentially dilutive share options that were not included in the computation of diluted EPS because to do so would be anti-dilutive.	53		83
[1]	Earnings allocated to common shareholders for basic and diluted EPS may differ under the two-class method as a result of adding common stock equivalents for options and warrants to dilutive shares outstanding, which alters the ratio used to allocate earnings to common shareholders and participating securities for the purposes of calculating diluted EPS.

Subsequent_Event_Details

Subsequent Event (Details)	Mar. 31, 2015	Dec. 31, 2014	Apr. 23, 2015
In Thousands, unless otherwise specified
Subsequent Event [Line Items]
Common Stock, Shares Authorized	63,033	63,033
Subsequent Event [Member]
Subsequent Event [Line Items]
Common Stock, Shares Authorized			115,000