Statements of Comprehensive Income - USD ($)	12 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Net income	$ 12,292,315	$ 14,368,354	$ 11,135,875
Unrealized loss from marketable securities, net of tax	(295,088)	(131,410)	(679,869)
Comprehensive income	$ 11,997,227	$ 14,236,944	$ 10,456,006

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=68079674&loc=SL4569616-111683

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-Name Accounting Standards Codification
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-Section 55
-Paragraph 4K
-URI http://asc.fasb.org/extlink&oid=65897068&loc=SL4591552-111686

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Net Income
-URI http://asc.fasb.org/extlink&oid=51831255

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=51831270

Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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