Note 8 - Related Party Transactions - Activity in Loans (Details) - USD ($)	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Balance - Beginning of year	$ 345,314	$ 381,948
New loans and lines of credit advances	1,600	7,500
Principal repayments	(216,960)	(44,134)
Balance - End of year	$ 129,954	$ 345,314