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.

No definition available.

+ Details

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

+ Details

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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Acquisitions Finite Lived Intangible Assets Acquired as Part of a Business Combination (Details) - Core Deposits Intangibles - USD ($) $ in Thousands			12 Months Ended
	Jul. 24, 2015	Jul. 31, 2014	Dec. 31, 2016
Mountain West Bank
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired		$ 695
Finite-Lived Intangible Asset, Useful Life		10 years
United Bank [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired	$ 2,486
Finite-Lived Intangible Asset, Useful Life	10 years
Flathead Bank [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life			9 years