Note 4 - Investments - Components of Investments (Details) - USD ($)		Jun. 30, 2022		Jun. 30, 2021
Cost		$ 19,967,000		$ 14,363,000
Unrealized gains losses		(5,667,000)		3,895,000
Investments in equity securities		14,300,000		18,258,000
Amortized cost	[1]	8,576,000	[2]	8,741,000
Unrealized gains	[1]	4,588,000		8,308,000
Unrealized losses	[1]	(2,539,000)		0
Investments in debt securities	[1]	10,625,000	[2]	17,049,000
Amortized cost, held-to-maturity	[3]	1,000,000		1,000,000
unrecognized gains, held-to-maturity	[3]	0		3,000
unrecognized losses, held-to-maturity	[3]	(133,000)		0
fair value, held-to-maturity	[3]	867,000		1,003,000
Equity Securities International [Member]
Cost		6,680,000		7,076,000
Unrealized gains losses		(5,141,000)		3,922,000
Investments in equity securities		1,539,000		10,998,000
Equity Securities Domestic [Member]
Cost		45,000		45,000
Unrealized gains losses		(45,000)		(45,000)
Investments in equity securities		0		0
Mutual Funds Fixed Income [Member]
Cost		12,313,000		6,313,000
Unrealized gains losses		(175,000)		9,000
Investments in equity securities		12,138,000		6,322,000
Mutual Funds Global Equity [Member]
Cost		929,000		929,000
Unrealized gains losses		(306,000)		9,000
Investments in equity securities		$ 623,000		$ 938,000

[1] Changes in unrealized gains and losses are included in the statement of comprehensive income (loss), except for embedded derivatives. Changes in unrealized and realized gains and losses for embedded derivatives are included in earnings in the statement of operations.

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

[3] Held-to-maturity debt instruments are carried at amortized cost, and the fair value is classified as Level 2 according to the fair value hierarchy.