Note 2 - Investments - Investments With Fair Values Adjusted on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2022		Jun. 30, 2022
Investments in equity securities	$ 16,346		$ 16,428
Investments in debt securities	10,686	[1]	11,449
Fair Value, Recurring [Member]
Investments in equity securities	16,346		16,428
Investments in debt securities	10,686		11,449
Total investments carried at fair value	27,032		27,877
Fair Value, Nonrecurring [Member]
Total investments carried at fair value	1,436	[2]	781
Equity Securities International [Member]
Investments in equity securities	3,775		3,667
Equity Securities International [Member] | Fair Value, Recurring [Member]
Investments in equity securities	3,775		3,667
Mutual Funds Fixed Income [Member]
Investments in equity securities	11,963		12,138
Mutual Funds Fixed Income [Member] | Fair Value, Recurring [Member]
Investments in equity securities	11,963		12,138
Mutual Funds Global Equity [Member]
Investments in equity securities	608		623
Mutual Funds Global Equity [Member] | Fair Value, Recurring [Member]
Investments in equity securities	608		623
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investments in equity securities	13,671		13,785
Investments in debt securities	0		0
Total investments carried at fair value	13,671		13,785
Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Total investments carried at fair value	0	[2]	0
Fair Value, Inputs, Level 1 [Member] | Equity Securities International [Member] | Fair Value, Recurring [Member]
Investments in equity securities	1,100		1,024
Fair Value, Inputs, Level 1 [Member] | Mutual Funds Fixed Income [Member] | Fair Value, Recurring [Member]
Investments in equity securities	11,963		12,138
Fair Value, Inputs, Level 1 [Member] | Mutual Funds Global Equity [Member] | Fair Value, Recurring [Member]
Investments in equity securities	608		623
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investments in equity securities	0		0
Investments in debt securities	0		0
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
Fair Value, Inputs, Level 2 [Member] | Equity Securities International [Member] | Fair Value, Recurring [Member]
Investments in equity securities	0		0
Fair Value, Inputs, Level 2 [Member] | Mutual Funds Fixed Income [Member] | Fair Value, Recurring [Member]
Investments in equity securities	0		0
Fair Value, Inputs, Level 2 [Member] | Mutual Funds Global Equity [Member] | Fair Value, Recurring [Member]
Investments in equity securities	0		0
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investments in equity securities	2,675		2,643
Investments in debt securities	10,686		11,449
Total investments carried at fair value	13,361		14,092
Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Total investments carried at fair value	1,436	[2]	781
Fair Value, Inputs, Level 3 [Member] | Equity Securities International [Member] | Fair Value, Recurring [Member]
Investments in equity securities	2,675		2,643
Fair Value, Inputs, Level 3 [Member] | Mutual Funds Fixed Income [Member] | Fair Value, Recurring [Member]
Investments in equity securities	0		0
Fair Value, Inputs, Level 3 [Member] | Mutual Funds Global Equity [Member] | Fair Value, Recurring [Member]
Investments in equity securities	$ 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 three months ended September 30, 2022. These securities are classified as level 3 due to the infrequency of the observable price changes and/or restrictions on the shares.