ADVANCES FROM FEDERAL HOME LOAN BANK OF DES MOINES (Details) - USD ($)	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Advance from Federal Home Loan Bank [Abstract]
Federal Home Loan Bank, advances, collateral pledged	$ 0	$ 0
Federal Home Loan Bank, Advances, Fiscal Year Maturity [Abstract]
Maturing in one year or less	323,000,000	50,000,000
Total FHLB advances	$ 323,000,000	$ 50,000,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate	5.64%	4.60%
Federal Home Loan Bank, advances, average interest rate for year	5.64%	4.60%
Federal Home Loan Bank, advances, maximum outstanding at any month end	$ 645,000,000	$ 75,000,000
Federal Home Loan Bank, advances, average balance outstanding	$ 196,800,000	$ 15,300,000
Federal Home Loan Bank, Advances, Activity for Year, Average Interest Rate for Year	5.35%	3.20%
Federal Home Loan Bank, Advances, General Debt Obligations, Amount of Available, Unused Funds	$ 2,970,000,000
Subsidiary, Banner Bank [Member]
Federal Home Loan Bank, Advances, Fiscal Year Maturity [Abstract]
Federal Home Loan Bank, advances, percentage of total assets to support credit line	45.00%

Federal Home Loan Bank, Advances, General Debt Obligations, Percentage of Total Assets to Support Credit Line

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- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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- Definition

The calculated average balance outstanding for the year for all Federal Home Loan Bank advances as of the Balance Sheet date.

+ References

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- Definition

The calculated weighted average interest rate for Federal Home Loan Bank advances for the period ended as of the Balance Sheet date.

+ References

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- Definition

The maximum balance outstanding at any month end during the period as of the Balance Sheet date.

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- Definition

Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(3)(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

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-Name Accounting Standards Codification
-Section 45
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-URI https://asc.fasb.org//1943274/2147480876/942-470-45-1

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22 (b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
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- Definition

Interest rate of advances made and reported by Federal Home Loan Bank (FHLBank).

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No definition available.

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- Definition

Weighted average interest rate of advance from Federal Home Loan Bank (FHLBank) due in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of advance from Federal Home Loan Bank (FHLBank) maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
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