Note 6 - Investment Securities Available for Sale (Details Textual) - USD ($)	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Proceeds from Sale of Available-for-sale Securities, Total	$ 11,608,699	$ 4,282,233
Gain on Sale of Investments	57,099	35,441
Loss on Sale of Investments	59,455	9,995
Proceeds from Sale of Short-term Investments		1,730,273
Available-for-sale Securities, Amortized Cost Basis, Total	78,267,079	104,616,155
Available-for-sale Securities, Total	75,404,136	102,429,128
Pledged Financial Instruments, Not Separately Reported, Securities, Total	744,186	744,186
Collateral Pledged [Member]
Debt Securities, Available-for-sale, Restricted	723,023	736,412
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Available-for-sale Securities, Amortized Cost Basis, Total	61,078,665	81,994,305
Available-for-sale Securities, Total	59,025,420	80,832,464
Fraternity Community Bancorp, Inc. [Member] \| Mortgage-backed Securities, Issued by Private Enterprises [Member]
Available-for-sale Securities, Amortized Cost Basis, Total	75,645
Available-for-sale Securities, Total	$ 76,803
Certificates of Deposit [Member]
Proceeds from Sale of Short-term Investments		1,730,273
Gain (Loss) on Sale of Investments, Total		$ (1,726)

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

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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.

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Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
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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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