Note 5 - Debt Securities - Held to Maturity Investments Classified by Contractual Maturity Date (Details) $ in Thousands	Mar. 31, 2024 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	4,003
Debt securities, held to maturity, fair value, maturity, allocated and single maturity date, after year 5 through 10	3,809
Debt securities, held to maturity, amortized cost, maturity, allocated and single maturity date, after year 10	89,734
Debt securities, held to maturity, fair value, maturity, allocated and single maturity date, after year 10	83,220
Debt securities, held to maturity, amortized cost, maturity, allocated and single maturity date, amortized cost	93,737
Debt securities, held to maturity, fair value, maturity, allocated and single maturity date, fair value	$ 87,029

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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