The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

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Marketable Securities (Narratives) (Details) - USD ($)	3 Months Ended		12 Months Ended
Marketable Securities (Narratives) (Details) - USD ($)	Jun. 30, 2020	Jun. 30, 2019	Mar. 31, 2020	Dec. 21, 2017
Gain (Loss) on Securities [Line Items]
Marketable Securities, Realized Gain (Loss)	$ 0	$ 50,000
Unrealized Gain on Securities	341,000	137,000
EMC [Member]
Gain (Loss) on Securities [Line Items]
Equity Method Investment, Ownership Percentage				49.00%
Increase (Decrease) in Accounts Receivable, Related Parties	4,940,000		$ 4,166,000
Equity Method Investments	3,657,000		$ 3,402,000
Investment Income, Net	$ 194,000	$ 110,000