Note 8 - Income Taxes: Schedule of Provision for Income Tax Expense (Benefit) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Details
Current Federal Tax Expense (Benefit)			$ 1,799,694	$ 1,249,565
Deferred Income Tax Expense (Benefit)			278,054	(20,937)
Income tax provision	$ 768,539	$ 655,904	$ 2,077,748	$ 1,228,628