Note 7 - Loans Receivable and Allowance for Loan Losses - Number of Contracts and Outstanding Loan Balance at Time of Modification (Details) - Real Estate Loans [Member] - Residential [Member]	12 Months Ended
Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)
Number of contracts	3	3
Outstanding recorded investment	$ 52,363	$ 97,401

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration