Business Acquisition, Conversion Share Rate, Shares

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- Definition

Estimate of Payments to Acquire Businesses, Gross

+ References

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- Definition

Estimate value per share of Acquisition

+ References

No definition available.

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- Definition

Number Of Banking Offices Acquired

+ References

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- Definition

Ownership Percentage in Partnership

+ References

No definition available.

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12069-110248

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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

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- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25336-109308

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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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Commitments and Contingencies - Narrative (Details) $ / shares in Units, $ in Millions		12 Months Ended
	Oct. 11, 2018 USD ($) $ / shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Oct. 05, 2018 $ / shares shares
Unrecorded Unconditional Purchase Obligation
Operating leases, rent expense		$ 3.2	$ 2.5	$ 1.9
Construction Contracts
Unrecorded Unconditional Purchase Obligation
Commitments under construction contracts		$ 2.7
Related Entity
Unrecorded Unconditional Purchase Obligation
Ownership percentage in partnership		50.00%
Idaho Independent Bank [Member]
Unrecorded Unconditional Purchase Obligation
Number of banking offices	11
Estimate of Payments to Acquire Businesses, Gross	$ 181.3
Community 1st Bank [Member]
Unrecorded Unconditional Purchase Obligation
Number of banking offices	3
Estimate of Payments to Acquire Businesses, Gross	$ 21.5
Inland Northwest Bank [Member]
Unrecorded Unconditional Purchase Obligation
Estimate value per share of Acquisition \| $ / shares	$ 22.73
Community 1st Bank [Member]
Unrecorded Unconditional Purchase Obligation
Estimate value per share of Acquisition \| $ / shares	$ 17.20
Class A Common Stock \| Community 1st Bank [Member]
Unrecorded Unconditional Purchase Obligation
Estimate value per share of Acquisition \| $ / shares					$ 45.45
Business Acquisition, Conversion Share Rate, Shares \| shares					0.3784
Class A Common Stock \| Idaho Independent Bank [Member]
Unrecorded Unconditional Purchase Obligation
Estimate value per share of Acquisition \| $ / shares					$ 45.45
Business Acquisition, Conversion Share Rate, Shares \| shares					0.5000
Mortgage loans originated for sale
Unrecorded Unconditional Purchase Obligation
Guarantor Obligations, Current Carrying Value		$ 1.5	$ 1.9