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Securities (Carrying Value of Securities Pledged as Collateral) (Details) $ in Thousands | Sep. 30, 2018 USD ($)
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Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Available-for-sale, Restricted | $ 427,902
Washington and Oregon State Public Deposits [Member] |
Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Available-for-sale, Restricted | 256,078
Federal Reserve Bank Advances [Member] |
Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Available-for-sale, Restricted | 51,843
Other Securities [Member] |
Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Available-for-sale, Restricted | $ 119,981

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- Definition Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b)(1)(i) -URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729 + Details
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Balance Type: | debit
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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