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Securities (Carrying Value of Securities Pledged as Collateral) (Details) $ in Thousands | Mar. 31, 2018 USD ($)
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Schedule of Available-for-sale Securities [Line Items] |
Carrying amount of securities pledged as collateral | $ 402,067
Washington and Oregon State Public Deposits [Member] |
Schedule of Available-for-sale Securities [Line Items] |
Carrying amount of securities pledged as collateral | 246,950
Federal Reserve Bank Advances [Member] |
Schedule of Available-for-sale Securities [Line Items] |
Carrying amount of securities pledged as collateral | 52,754
Other Securities [Member] |
Schedule of Available-for-sale Securities [Line Items] |
Carrying amount of securities pledged as collateral | $ 102,363

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- Definition The fair value of available-for-sale securities that serve as collateral for borrowings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5086-111524 + Details
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Period Type: | instant

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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- Details
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