The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

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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.

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- Definition

The date of the transaction involving the sale of the property to another party and the lease of the property back to the seller.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77913982&loc=d3e50796-112755

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 40
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=77888430&loc=SL77919786-209982

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- Definition

The amount of the gain recorded in connection with the transaction involving the sale of property to another party and the lease of the property back to the seller to be recognized in future periods.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 25
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=77913853&loc=d3e49567-112750

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- Definition

The portion of the gain that will be recorded as income or a reduction in rent expense in future periods less amounts recognized in the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 35
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77907795&loc=d3e50609-112754

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- Definition

The amount of the monthly rental payments due under the lease entered into in connection with the transactions involving the sale of property to another party and the lease of the property back to the seller.

+ References

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Commitments and Contingent Liabilities (Details) - USD ($) $ in Thousands			9 Months Ended
	Aug. 11, 2017	Aug. 24, 2016	Sep. 30, 2017	Dec. 31, 2016
Commitments to Extend Credit [Member]
Other Commitments [Line Items]
Fair Value Disclosure, Off-balance Sheet Risks, Amount, Liability			$ 2,230,000	$ 2,170,000
Standby Letters of Credit [Member]
Other Commitments [Line Items]
Fair Value Disclosure, Off-balance Sheet Risks, Amount, Liability			50,100	49,700
Commercial Letter of Credit and other off-balance sheet liabilities [Member]
Other Commitments [Line Items]
Fair Value Disclosure, Off-balance Sheet Risks, Amount, Liability			2,900	$ 3,400
IDAHO
Other Commitments [Line Items]
Sale Leaseback Transaction, Date	August 11, 2017
Sale Leaseback Transaction, Monthly Rental Payments			26
Sale Leaseback Transaction, Deferred Gain, Gross	$ 509
Sale Leaseback Transaction, Deferred Gain, Net			501
WASHINGTON
Other Commitments [Line Items]
Sale Leaseback Transaction, Date		August 24, 2016
Sale Leaseback Transaction, Monthly Rental Payments			12
Sale Leaseback Transaction, Deferred Gain, Gross		$ 742
Sale Leaseback Transaction, Deferred Gain, Net			$ 661