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Deferred amounts of principal and interest payments on loans receivable related to loan modification programs offered to financial institution customers affected by COVID-19.

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The decrease in the appraisal value of an impaired loan when it is classified as non-performing, represented as a percent.

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

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Period of time that a loan receivable takes to reset to the FHLB rate, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Maximum percentage of credit extension based on market value of collateral.

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Maximum period for charged off of consumer installment loans.

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Maximum period of credit extension of construction loans.

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The number of impaired loans held.

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The number of impaired financing receivables that were collectively evaluated for impairment.

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No definition available.

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The number of impaired financing receivables that were individually evaluated for impairment.

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No definition available.

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Percentage of maximum loan to value.

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Represents percentage of principal balance guaranteed.

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Period for charged off of close end credits.

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Period for charged off of open end credits

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Amount of allowance for credit losses related to recorded investment.

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Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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The cash outflow for the purchase of loan receivable arising from the financing of goods and services.

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Value of loans held-for-sale transferred to loans held in the entity's portfolio in noncash transactions.

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Note 4 - Loan Receivable and Allowance for Loan and Lease Losses (Details Textual)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Payments to Acquire Loans Receivable			$ 44,783,000	$ 29,017,000
Maximum Period of Credit Extension of Construction Loans (Month)			18 months
Loans Receivable, Term to Reset to FHLB Rate (Year)			5 years
Period for Charged Off of Open-End Credits (Day)			180 days
Period for Charged Off of Close-End Credits (Day)			120 days
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	$ 154,000	$ 284,000	$ 409,000	$ 475,000
Maximum Period for Charged Off of Consumer Installment Loans (Day)					180 days
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0	0	0
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend	$ 0		$ 0		$ 0
Financing Receivable, Principal and Interest Deferred Payments	232,700,000		232,700,000
Financing Receivable, Loans Remaining on Deferment	$ 21,300,000		$ 21,300,000
Number of Impaired Loans	34		34		26
Impaired Financing Receivable, Recorded Investment, Total	$ 29,300,000		$ 29,300,000		$ 24,400,000
Impaired Financing Receivable, Related Allowance	$ 1,700,000		$ 1,700,000		$ 1,400,000
Number of Impaired Loans, Individually Evaluated for Impairment	21		21
Number of Impaired Loans, Collectively Evaluated for Impairment	10		10
Impaired Financing Receivable, Non-Performing Loans, Discount to Appraisal Value, Percent	8.00%		8.00%		5.80%
SBA Loans [Member]
Transfer of Loans Held-for-sale to Portfolio Loans			$ 281,000	$ 8,001,000
SBA Loans [Member] \| Minimum [Member]
Percentage of Principal Balance Guaranteed	75.00%		75.00%
SBA Loans [Member] \| Maximum [Member]
Percentage of Principal Balance Guaranteed	90.00%		90.00%
SBA CARES Act Paycheck Protection Program [Member]
Loans and Leases Receivable, Net Amount, Total	$ 2,900,000		$ 2,900,000
Syndicated and Leveraged Loans [Member]
Loans and Leases Receivable, Net Amount, Total	38,600,000		38,600,000		$ 55,000,000.0
Non-Accrual Loans [Member]
Impaired Financing Receivable, Interest Income, Cash Basis Method, Total	77,000	$ 57,000	$ 121,000	84,000
Commercial Real Estate Portfolio Segment [Member]
Maximum Percentage of Credit Extension Based on Market Value of Collateral			75.00%
Multi-family Real Estate [Member]
Maximum Percentage of Credit Extension Based on Market Value of Collateral			80.00%
Construction Portfolio Segment [Member]
Percentage of Maximum Loan to Value			75.00%
Residential Portfolio Segment [Member]
Payments to Acquire Loans Receivable	26,700,000	6,000,000.0	$ 42,700,000	14,100,000
Consumer Portfolio Segment [Member] \| Education Loans [Member]
Payments to Acquire Loans Receivable	2,100,000	$ 0	$ 2,100,000	$ 14,900,000
Construction to Permanent Portfolio Segment [Member]
Loans Receivable, Term (Year)			10 years
Commercial and Industrial Loans [Member]
Loans and Leases Receivable, Net Amount, Total	$ 22,900,000		$ 22,900,000		$ 21,600,000