Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Debt Term.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Description of reference rate used for variable rate of debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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Date the debt instrument was issued, in YYYY-MM-DD format.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of advances from the Federal Home Loan Bank (FHLB).

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

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The year of maturity, when only one maturity date applies, for the advances from the Federal Home Loan Bank as of the Balance Sheet date.

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States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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The effective interest rate during the reporting period.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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Borrowing Arrangements - Additional Information (Detail) - USD ($)				6 Months Ended	9 Months Ended
	May 31, 2020	Apr. 30, 2020	Apr. 15, 2016	Jun. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Jun. 30, 2019
Short-term Debt [Line Items]
FHLB Advance, Collateral Pledged				$ 193,600,000		$ 129,300,000
FHLB Advance, Available Borrowing Capacity				147,600,000		68,300,000
FHLB Advance, Amount Of Advances	$ 5,000,000.0			0		5,000,000.0	$ 10,000,000.0
FHLB Advance, Term	1 year
FHLB Advance, Maturity Date	2021
FHLB Advance, Interest Rate	0.00%						1.89%
Junior Subordinated debt securities				24,745,000		24,994,000
Federal Home Loan Ten Million Outstanding [Member]
Short-term Debt [Line Items]
Federal home loan banks term borrowings outstanding				0		10,000,000.0
Junior Subordinated Debt [Member]
Short-term Debt [Line Items]
Debt Instrument, Face Amount			$ 5,000,000.0
Debt Instrument, IssuanceDate			Apr. 15, 2016		Sep. 30, 2020
Debt Instrument, Interest Rate Terms			The subordinated debt has a fixed interest rate of 5.875% for the first 5 years		The subordinated debt has a fixed interest rate of 5.00% for the first 5 years
Debt Instrument, Fixed Interest Rate			5.875%		5.00%
Related issuance costs			$ 87,000	300,000,000,000
Junior Subordinated debt securities				$ 5,000,000.0		5,000,000.0
Prime Rate [Member] \| Junior Subordinated Debt [Member]
Short-term Debt [Line Items]
Debt Instrument, Variable Interest Rate Basis			variable rate of prime plus 2.00%
Debt Instrument, Variable Rate			2.00%
SOFR [Member] \| Junior Subordinated Debt [Member]
Short-term Debt [Line Items]
Debt Instrument, Variable Interest Rate Basis					variable rate equal to then current three-month term SOFR plus 0.488%
Debt Instrument, Variable Rate				0.488%
Debt Instrument, Face Amount					$ 20,000,000.0
Junior Subordinated debt securities				$ 20,000,000.0		20,000,000.0
Correspondent Banks [Member]
Short-term Debt [Line Items]
Borrowings outstanding				0		0
Line Of Credit Maximum Borrowing Capacity				116,000,000.0
Secured Debt [Member]
Short-term Debt [Line Items]
Borrowings outstanding				0		0
Line Of Credit Maximum Borrowing Capacity				$ 12,000,000.0
Line of Credit Facility, Expiration Period				3 years
Line Of Credit, Fixed Interest Rate				3.95%
Secured Debt [Member] \| Federal Reserve Bank of San Francisco [Member]
Short-term Debt [Line Items]
Loans Pledged As Collateral				$ 326,000,000.0		458,700,000
Line Of Credit Available Borrowing Capacity				217,600,000		358,500,000
Revolving Credit Facility [Member]
Short-term Debt [Line Items]
Borrowings outstanding				0		$ 0
Line Of Credit Maximum Borrowing Capacity				$ 5,000,000.0
Revolving Credit Facility [Member] \| One Year Prime Rate [Member]
Short-term Debt [Line Items]
Debt Instrument, Variable Interest Rate Basis				six month term at a rate of Prime plus 0.40%
Debt Instrument, Variable Rate				0.40%
Paycheck Protection Liquidity Facility [Member]
Short-term Debt [Line Items]
Borrowings outstanding				$ 0
Line Of Credit Maximum Borrowing Capacity		$ 332,700,000
Line of Credit Facility, Expiration Period		2 years
Line Of Credit, Fixed Interest Rate		0.35%