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FHLB Advances and Other Borrowings - Narrative (Details)	12 Months Ended
	Sep. 30, 2021 USD ($)
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
FHLB advances callable as of August 7, 2020 and quarterly thereafter	$ 100,000,000
Weighted average effective maturity of FHLB advances	5 years 10 days
Federal Home Loan Bank of Des Moines
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal home loan bank, percent of assets	45.00%

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- Definition

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- Definition

Par amount of advances made and reported by Federal Home Loan Bank (FHLBank) with the earlier of contractual maturity or next call date within the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Federal Home Loan Bank, Advances, Weighted Average Effective Maturity

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Federal Home Loan Bank, Line of Credit, Maximum Borrowing Capacity, Percentage of Assets

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