Short-Term And Long-Term Investments (Schedule Of Short-Term And Long-Term Investments) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020
Investments, Debt and Equity Securities Statement [Line Items]
Short-term investments	$ 427	$ 355
Long-term investments	725	725
Bank Guarantees [Member]
Investments, Debt and Equity Securities Statement [Line Items]
Short-term investments	427	355
Cost [Member]
Investments, Debt and Equity Securities Statement [Line Items]
Short-term investments	427	355
Long-term investments	3,700	3,700
Total Investments	4,127	4,055
Cost [Member] | Bank Guarantees [Member]
Investments, Debt and Equity Securities Statement [Line Items]
Short-term investments	427	355
Cost [Member] | Preferred Stock [Member]
Investments, Debt and Equity Securities Statement [Line Items]
Long-term investments	3,700	3,700
Fair Value Or Carrying Value [Member]
Investments, Debt and Equity Securities Statement [Line Items]
Short-term investments	427	355
Long-term investments	725	725
Total Investments	1,152	1,080
Fair Value Or Carrying Value [Member] | Bank Guarantees [Member]
Investments, Debt and Equity Securities Statement [Line Items]
Short-term investments	427	355
Fair Value Or Carrying Value [Member] | Preferred Stock [Member]
Investments, Debt and Equity Securities Statement [Line Items]
Long-term investments	$ 725	$ 725