v2.4.0.6
Securities (Carrying Value of Securities Pledged as Collateral) (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2011
Dec. 31, 2010
Schedule of Available-for-sale Securities [Line Items]    
Carrying amount of securities pledged as collateral $ 420,243 $ 458,532
To Washington and Oregon State To Secure Public Deposits [Member]
   
Schedule of Available-for-sale Securities [Line Items]    
Carrying amount of securities pledged as collateral 225,345 153,328
To Federal Home Loan Bank To Secure Advances [Member]
   
Schedule of Available-for-sale Securities [Line Items]    
Carrying amount of securities pledged as collateral 91,097 110,780
To Federal Reserve Bank To Secure Borrowings [Member]
   
Schedule of Available-for-sale Securities [Line Items]    
Carrying amount of securities pledged as collateral 56,347 149,315
Other Securities [Member]
   
Schedule of Available-for-sale Securities [Line Items]    
Carrying amount of securities pledged as collateral $ 47,454 $ 45,109