Note 5 - Debt Securities - Held to Maturity Investments Classified by Contractual Maturity Date (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Debt securities, held to maturity, amortized cost, maturity, allocated and single maturity date, year one	$ 0
Debt securities, held to maturity, fair value, maturity, allocated and single maturity date, year one	0
Debt securities, held to maturity, amortized cost, maturity, allocated and single maturity date, after year one through five	0
Debt securities, held to maturity, fair value, maturity, allocated and single maturity date, after year one through five	0
Debt securities, held to maturity, amortized cost, maturity, allocated and single maturity date, after year 5 through 10	2,826
Debt securities, held to maturity, fair value, maturity, allocated and single maturity date, after year 5 through 10	2,527
Debt securities, held to maturity, amortized cost, maturity, allocated and single maturity date, after year 10	93,814
Debt securities, held to maturity, fair value, maturity, allocated and single maturity date, after year 10	81,558
Debt securities, held to maturity, amortized cost, maturity, allocated and single maturity date, amortized cost	96,640
Debt securities, held to maturity, fair value, maturity, allocated and single maturity date, fair value	$ 84,085

Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in sixth through tenth 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).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in second through fifth 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).

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