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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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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The increase (decrease) during the reporting period in the amount due to the reporting entity for good and services provided to the following types of related parties: a parent company and its subsidiaries; subsidiaries of a common parent; an entity and trust for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management, an entity and its principal owners, management, member of their immediate families, affiliates, or other parties with the ability to exert significant influence.

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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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Amount of realized gain (loss) on investment in marketable security, including other-than-temporary impairment (OTTI).

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Amount of distribution received from equity method investee for return of investment, classified as investing activities. Excludes distribution for return on investment, classified as operating activities.

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The increase (decrease), resulting in a gain, in the difference between the fair value and the carrying value, or in the comparative fair values, of securities held at each balance sheet date, that was included in earnings for the period.

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Marketable Securities (Narratives) (Details) - USD ($)	3 Months Ended		9 Months Ended
Marketable Securities (Narratives) (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Mar. 31, 2019	Dec. 21, 2017
Gain (Loss) on Securities [Line Items]
Marketable Securities, Realized Gain (Loss)	$ 50,000		$ 50,000
Unrealized Gain on Securities	67,000	$ 422,000	232,000	$ 317,000
Proceeds from Equity Method Investment, Distribution, Return of Capital			666,000
EMC [Member]
Gain (Loss) on Securities [Line Items]
Equity Method Investment, Ownership Percentage						49.00%
Increase (Decrease) in Accounts Receivable, Related Parties			5,032,000
Equity Method Investments	3,451,000		3,451,000		$ 3,602,000
Investment Income, Net	$ 223,000	$ 230,000	$ 515,000	$ 402,000