Business Combinations (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended
	Jan. 29, 2010 American Marine Bank [Member]	May 20, 2011 Summit Bank [Member]	Aug. 05, 2011 Bank of Whitman [Member]	May 27, 2011 First Heritage Bank [Member]	Jan. 22, 2010 Columbia River 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, Effective Date of Acquisition	Jan. 29, 2010	May 20, 2011	Aug. 05, 2011	May 27, 2011	Jan. 22, 2010
Business Acquisition, Purchase Price Allocation, Current Assets, Cash and Cash Equivalents	$ 14,215	$ 1,837	$ 52,072	$ 4,688	$ 33,222
Business Acquisition, Purchase Price Allocation, Current Assets, Federal Funds sold	267
Business Combination, Acquired Receivables, Fair Value	176,278	69,783	200,041	81,488	480,306	71,400	81,900
Business Acquisition, Purchase Price Allocation, Current Assets, Marketable Securities	28,592	871	16,298	5,303	100,650
Business Acquisition, Purchase Price Allocation, Federal Reserve Bank and Federal Home Loan Bank Stock			3,977
Business Acquisition, Purchase Price Allocation, Accrued Interest Receivable	1,280	429	1,975	476	4,021
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment		42	86	5,339
Business Acquisition, Purchase Price Allocation, FDIC Receivable		6,984	156,710	4,751
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets	4,313	509	3,943	1,337	13,442
Business Acquisition, Purchase Price Allocation, Other Assets	498	1,813	2,447	3,657	615	786	1,700
Business Acquisition, Purchase Price Allocation, Assets Acquired	307,822	131,129	437,549	164,984	912,878
Business Acquisition, Purchase Price Allocation, Liabilities, Deposits	253,965	123,279	401,127	159,525	893,356
Business Acquisition, Purchase Price Allocation, Federal Home Loan Bank Advances	37,682	7,772	32,949	5,003	18,428
Business Acquisition, Purchase Price Allocation, Current Liabilities, Accrued Liabilities	337	71	213	421	524
Business Acquisition, Purchase Price Allocation, Deferred Taxes Asset (Liability), Net, Noncurrent	5,383		1,034
Business Acquisition, Purchase Price Allocation, Other Noncurrent Liabilities	637	7	396	35	570
Business Acquisition, Purchase Price Allocation, Liabilities Assumed	298,004	131,129	435,719	164,984	912,878
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	9,818		1,830
Business Acquisition, Purchase Price Allocation, Interest Earning Deposits With Banks				6,689	64,921
Business Acquisition, Purchase Price Allocation, FHLB Stock	3,257	406		477	3,045
Business Acquisition, Purchase Price Allocation, Loans Covered By Loss Sharing	8,680	2,162		8,225	8,714	2,700	8,300
Business Acquisition, Purchase Price Allocation, Goodwill Amount		1,892		4,023	14,120
Business Acquisition, Purchase Price Allocation, FDIC Indemnification Asset	70,442	30,203		38,531	189,822	27,200	38,100
Business Acquisition, Purchase Price Allocation, Interest Earning Deposits With Banks And Federal Funds Sold		$ 14,198