Statements of Comprehensive Income (USD $)	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Comprehensive Income [Abstract]
Net income	$ 14,368,354us-gaap_NetIncomeLoss	$ 11,135,875us-gaap_NetIncomeLoss	$ 11,828,838us-gaap_NetIncomeLoss
Unrealized (gain) loss from marketable securities, net of tax	(131,410)	(679,869)	470,270
Comprehensive income	$ 14,236,944	$ 10,456,006	$ 12,299,108	$ 12,299,108

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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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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