Note 3 - Investments - Investments With Fair Values Adjusted on Recurring Basis (Details) - USD ($) $ in Thousands		Mar. 31, 2024		Jun. 30, 2023
Equity Securities, FV-NI		$ 11,311		$ 13,205
Total investments in trading securities:		11,506		13,205
Investments in debt securities	[1]	5,190
Corporate Debt Securities [Member]
Corporate debt securities, fair value		195		0
Convertible Debt Securities [Member]
Investments in debt securities		5,190		7,008
Fair Value, Recurring [Member]
Total investments carried at fair value		16,696		20,213
Fair Value, Nonrecurring [Member]
Total investments carried at fair value		600	[2]	1,786	[3]
Equity Securities International [Member]
Equity Securities, FV-NI		411		778
Equity Securities International [Member] | Fair Value, Recurring [Member]
Equity Securities, FV-NI		411		778
Mutual Funds Fixed Income [Member]
Equity Securities, FV-NI		10,071		11,642
Mutual Funds Fixed Income [Member] | Fair Value, Recurring [Member]
Equity Securities, FV-NI		10,071		11,642
Mutual Funds Global Equity [Member]
Equity Securities, FV-NI		829		785
Mutual Funds Global Equity [Member] | Fair Value, Recurring [Member]
Equity Securities, FV-NI		829		785
Fair Value, Inputs, Level 1 [Member]
Equity Securities, FV-NI		11,311		12,915
Total investments in trading securities:		11,506		12,915
Fair Value, Inputs, Level 1 [Member] | Corporate Debt Securities [Member]
Corporate debt securities, fair value		195		0
Fair Value, Inputs, Level 1 [Member] | Convertible Debt Securities [Member]
Investments in debt securities		0		0
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Total investments carried at fair value		11,506		12,915
Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Total investments carried at fair value		0	[2]	0	[3]
Fair Value, Inputs, Level 1 [Member] | Equity Securities International [Member] | Fair Value, Recurring [Member]
Equity Securities, FV-NI		411		488
Fair Value, Inputs, Level 1 [Member] | Mutual Funds Fixed Income [Member] | Fair Value, Recurring [Member]
Equity Securities, FV-NI		10,071		11,642
Fair Value, Inputs, Level 1 [Member] | Mutual Funds Global Equity [Member] | Fair Value, Recurring [Member]
Equity Securities, FV-NI		829		785
Fair Value, Inputs, Level 2 [Member]
Equity Securities, FV-NI		0		0
Total investments in trading securities:		0		0
Fair Value, Inputs, Level 2 [Member] | Corporate Debt Securities [Member]
Corporate debt securities, fair value		0		0
Fair Value, Inputs, Level 2 [Member] | Convertible Debt Securities [Member]
Investments in debt securities		0		0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Total investments carried at fair value		0		0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member]
Total investments carried at fair value		0	[2]	0	[3]
Fair Value, Inputs, Level 2 [Member] | Equity Securities International [Member] | Fair Value, Recurring [Member]
Equity Securities, FV-NI		0		0
Fair Value, Inputs, Level 2 [Member] | Mutual Funds Fixed Income [Member] | Fair Value, Recurring [Member]
Equity Securities, FV-NI		0		0
Fair Value, Inputs, Level 2 [Member] | Mutual Funds Global Equity [Member] | Fair Value, Recurring [Member]
Equity Securities, FV-NI		0		0
Fair Value, Inputs, Level 3 [Member]
Equity Securities, FV-NI		0		290
Total investments in trading securities:		0		290
Fair Value, Inputs, Level 3 [Member] | Corporate Debt Securities [Member]
Corporate debt securities, fair value		0		0
Fair Value, Inputs, Level 3 [Member] | Convertible Debt Securities [Member]
Investments in debt securities		5,190		7,008
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Total investments carried at fair value		5,190		7,298
Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Total investments carried at fair value		600	[2]	1,786	[3]
Fair Value, Inputs, Level 3 [Member] | Equity Securities International [Member] | Fair Value, Recurring [Member]
Equity Securities, FV-NI		0		290
Fair Value, Inputs, Level 3 [Member] | Mutual Funds Fixed Income [Member] | Fair Value, Recurring [Member]
Equity Securities, FV-NI		0		0
Fair Value, Inputs, Level 3 [Member] | Mutual Funds Global Equity [Member] | Fair Value, Recurring [Member]
Equity Securities, FV-NI		$ 0		$ 0

[1] Principal payments of $750,000 are due quarterly with a final maturity date in January 2026.

[2] Other investments include equity securities without readily determinable fair values that were adjusted as a result of the measurement alternative on dates during the nine months ended March 31, 2024. These securities are classified as level 3 due to the infrequency of the observable price changes and/or restrictions on the shares.

[3] Other investments include equity securities without readily determinable fair values that were adjusted as a result of the measurement alternative on dates during the fiscal year ended June 30, 2023. These securities are classified as level 3 due to the infrequency of the observable price changes and/or restrictions on the shares.