Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

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- Definition

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1),(2)
-URI http://asc.fasb.org/extlink&oid=109977999&loc=d3e76258-113986

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- Definition

Fair value of securities pledged as collateral against derivative liabilities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226013-175313

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The net amount of operating interest income (expense).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.10)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

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- Definition

Amount of unrealized gain (loss) related to derivatives designated as cash flow hedging instruments, recorded in results of operations to the extent that the cash flow hedge is determined to be ineffective.

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Note 7 - Derivative - Interest Rate Swap Agreement (Details Textual) - USD ($)	3 Months Ended			6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2015	Sep. 30, 2018	Sep. 30, 2017	Mar. 31, 2018
Derivative, Notional Amount	$ 11,550,000			$ 11,550,000
Interest Income (Expense), Net, Total	3,748,283	$ 3,610,782		7,556,401	$ 7,204,034
Interest Rate Swap [Member]
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	0	0		0	0
Interest Rate Swap [Member] \| Cash Flow Hedging [Member]
Derivative Liability, Fair Value of Collateral	758,000			758,000		$ 751,000
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net, Total	540	(3,679)		921	(3,679)
Interest Rate Swap [Member] \| Cash Flow Hedging [Member] \| Federal Home Loan Bank Advances [Member]
Derivative, Notional Amount	11,600,000			11,600,000
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net, Total	540	$ (3,679)		921	$ (3,679)
Interest Income (Expense), Net, Total	906			(1,832)
Interest Rate Swap [Member] \| Fair Value Hedging [Member]
Derivative, Notional Amount	$ 3,000,000		$ 3,300,000	$ 3,000,000
Derivative, Fixed Interest Rate			3.99%
Derivative, Term of Contract			10 years