Statements of Comprehensive Income (Unaudited) - USD ($)	3 Months Ended	6 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Net income	$ 3,161,035	$ 3,305,197	$ 6,458,650	$ 6,437,742
Unrealized gain (loss) from marketable securities, net of tax	12,738	(240,809)	67,765	(15,206)
Comprehensive income	$ 3,173,773	$ 3,064,388	$ 6,526,415	$ 6,422,536

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

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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