Marketable Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Marketable Securities [Abstract]
Marketable securities, cost	$ 15,919	$ 13,611	$ 9,539
Marketable securities, market value	16,327	12,020	9,803
Unrealized gain (loss) on marketable securities	1,999	(1,860)	954
Proceeds from sale of marketable securities	920	6,798	1,011
Realized gain from sale of marketable securities	$ 69	$ 526	$ 102

No definition available.

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- Definition

Amount of investments in equity securities and other forms of securities that provide ownership interests expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

+ References

No definition available.

+ Details

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- Definition

The cash inflow associated with the sale of securities classified as trading securities and held for investment purposes. Excludes proceeds from trading securities purchased and held principally for the purpose of selling them in the near term (thus held for only a short period of time).

+ References

No definition available.

+ Details

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- Definition

Cost of investments in equity securities and other forms of securities that provide ownership interests classified as trading.

+ References

No definition available.

+ Details

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- Definition

Amount of gain (loss) realized from securities classified as trading.

+ References

+ Details

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- Definition

Amount of unrealized holding gain (loss) recognized in the income statement for investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(c))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 35
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82895926&loc=d3e24584-111560

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563

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