Note 6 - Investment Securities Available for Sale (Details Textual) - USD ($)	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Proceeds from Sale of Available-for-sale Securities	$ 4,273,234	$ 19,228,336
Gain on Sale of Investments	35,441	325,259
Loss on Sale of Investments	9,995	53,700
Proceeds from Sale of Short-term Investments	1,730,273
Available-for-sale Securities, Amortized Cost Basis	104,616,155	70,520,431
Available-for-sale Securities	102,429,128	70,484,400
Pledged Financial Instruments, Not Separately Reported, Securities	744,186	2,000,000
Available-for-sale Securities Pledged as Collateral	736,412	$ 1,993,226
Mortgage-backed Securities, Issued by Private Enterprises [Member] \| Fraternity Community Bancorp, Inc. [Member]
Available-for-sale Securities, Amortized Cost Basis	94,390
Available-for-sale Securities	94,381
Certificates of Deposit [Member]
Proceeds from Sale of Short-term Investments	2,228,273
Gain (Loss) on Sale of Investments	$ (1,726)

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

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The fair value of available-for-sale securities that serve as collateral for borrowings.

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The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.

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The difference between the carrying value and the sale price of an investment. A gain would be recognized when the sale price of the investment is greater than the carrying value of the investment. This element refers to the Gain included in earnings and not to the cash proceeds of the sale.

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The difference between the carrying value and the sale price of an investment. A loss would be recognized when the sale price of the investment is less than the carrying value of the investment. This element refers to the Loss included in earnings and not to the cash proceeds of the sale.

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Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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The cash inflow from sales of all investments, including securities and other assets, having ready marketability and intended by management to be liquidated, if necessary, within the current operating cycle. Includes cash flows from securities classified as trading securities that were acquired for reasons other than sale in the short-term.

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