Business Combinations (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended		0 Months Ended	12 Months Ended		0 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Apr. 02, 2013 West Coast Bancorp [Member]	Dec. 31, 2013 West Coast Bancorp [Member]	Dec. 31, 2012 West Coast Bancorp [Member]	May 20, 2011 Summit Bank [Member]	Aug. 05, 2011 Bank of Whitman [Member]	May 27, 2011 First Heritage Bank [Member]	May 20, 2011 Scenario, Previously Reported [Member] Summit Bank [Member]	May 27, 2011 Scenario, Previously Reported [Member] First Heritage Bank [Member]
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Revenue				$ 337,712	$ 420,167
Business Acquisition, Effective Date of Acquisition			Apr. 01, 2013			May 20, 2011	Aug. 05, 2011	May 27, 2011
Business Acquisition, Purchase Price Allocation, Current Assets, Cash and Cash Equivalents			110,440			1,837	52,072	4,688
Business Combination, Acquired Receivables, Fair Value			1,407,798			69,783	200,041	81,488	71,400	81,900
Business Acquisition, Purchase Price Allocation, Current Assets, Marketable Securities			730,842			871	16,298	5,303
Business Acquisition, Purchase Price Allocation, Federal Reserve Bank and Federal Home Loan Bank Stock							3,977
Business Acquisition, Purchase Price Allocation, Accrued Interest Receivable						429	1,975	476
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment			35,884			42	86	5,339
Business Acquisition, Purchase Price Allocation, FDIC Receivable						6,984	156,710	4,751
Business Combination, Purchase Price Allocation, Amortizable Intangible Assets			15,257			509	3,943	1,337
Business Combination, Purchase Price Allocation, Other Assets			75,820			1,813	2,447	3,657	786	1,700
Business Acquisition, Purchase Price Allocation, Assets Acquired						131,129	437,549	164,984
Business Acquisition, Purchase Price Allocation, Liabilities, Deposits			(1,883,407)			(123,279)	(401,127)	(159,525)
Business Acquisition, Purchase Price Allocation, Federal Home Loan Bank Advances			(128,885)			(7,772)	(32,949)	(5,003)
Business Acquisition, Purchase Price Allocation, Current Liabilities, Accrued Liabilities						71	213	421
Business Acquisition, Purchase Price Allocation, Deferred Taxes Asset (Liability), Net, Noncurrent							1,034
Business Acquisition, Purchase Price Allocation, Other Noncurrent Liabilities			(26,888)			(7)	(396)	(35)
Business Acquisition, Purchase Price Allocation, Liabilities Assumed						131,129	435,719	164,984
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net			312,393				1,830
Business Acquisition, Purchase Price Allocation, Interest Earning Deposits With Banks								6,689
Business Acquisition, Purchase Price Allocation, FHLB Stock			11,824			406		477
Business Acquisition, Purchase Price Allocation, Loans Covered By Loss Sharing						2,162		8,225	2,700	8,300
Business Combination, Purchase Price Allocation, Goodwill Amount			228,398			1,892		4,023
Business Acquisition, Purchase Price Allocation, FDIC Indemnification Asset						30,203		38,531	27,200	38,100
Business Acquisition, Purchase Price Allocation, Interest Earning Deposits With Banks And Federal Funds Sold						14,198
Business Acquisition, Cost of Acquired Entity, Purchase Price			540,791
Business Acquisition, Purchase Price Allocation, Other Real Estate Owned			14,708
Business Acquisition, Purchase Price Allocation, Junior Subordinated Debentures			(51,000)
Business Acquisition, Pro Forma Net Income (Loss)	$ 76,496	$ 91,261
Business Acquisition, Pro Forma Earnings Per Share, Basic				$ 1.50	$ 1.79
Business Acquisition, Pro Forma Earnings Per Share, Diluted				$ 1.46	$ 1.74