Federal Home Loan Bank Advances and Other Borrowings (Details) - USD ($)	6 Months Ended	12 Months Ended
Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Borrowings from the FHLB	$ 130,000,000.0	$ 20,000,000.0
FHLB, Fixed-rate borrowings	$ 130,000,000.0
Weighted average interest rate	0.51%	1.92%
Loans pledged to secure borrowings	$ 580,600,000	$ 621,700,000
Additional borrowing capacity	320,000,000.0	404,800,000
FHLB of San Francisco
Debt Instrument [Line Items]
Investment in capital stock of the FHLB	8,300,000	$ 8,200,000
FHLB Advances
Debt Instrument [Line Items]
Unused borrowing capacity	40,300,000
Loans pledged as collateral	48,900,000
Borrowings outstanding	0
Overnight federal funds lines, maximum borrowing capacity	$ 65,000,000.0
FHLB Advances \| Minimum
Debt Instrument [Line Items]
Maturity term	6 months	3 years
FHLB Advances \| Maximum
Debt Instrument [Line Items]
Maturity term	5 years	5 years

Amount of assets pledged to secure a debt instrument.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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Amount of advances or credit lines available 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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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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Amount of Federal Home Loan Bank (FHLB) advances which have fixed interest.

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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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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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The carrying value as of the balance sheet date of the current portion 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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