Note 20 - Condensed Financial Statements of Parent Company - Condensed Statements of Cash Flows (Details) - USD ($)	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities
Net loss	$ (6,048,942)	$ (928,782)
Reconciliation of net loss to net cash provided by operating activities
Increase (decrease) in other assets	(1,074,989)	2,565,464
Decrease in other liabilities	(217,056)	(1,642,208)
Net cash provided (used) by operating activities	1,673,758	543,965
Cash flows from investing activities
Acquisition, net of cash acquired		(10,508,813)
Loans made, net of principal repayments	2,256,439	(10,461,510)
Proceeds from maturing and called securities available for sale, including principal pay downs	15,124,739	28,963,565
Purchase of investment securities available-for-sale	(1,208,990)	(50,585,898)
Net cash provided (used) by investing activities	(25,676,905)	(34,822,132)
Cash flows from financing activities
Redemption of restricted stock	(54,400)	(69,068)
Net cash (used) provided by financing activities	18,017,641	(3,816,448)
Net increase (decrease) in cash and cash equivalents	(5,985,506)	(38,094,615)
Cash and cash equivalents at beginning of period	29,353,921	67,448,536
Cash and cash equivalents at end of period	23,368,415	29,353,921
Parent Company [Member]
Cash flows from operating activities
Net loss	(6,048,942)	(928,782)
Reconciliation of net loss to net cash provided by operating activities
Equity in undistributed net loss of subsidiary	5,922,357	670,456
Amortization of premium on investment securities	13,034	4,707
Increase (decrease) in other assets	119,768	(9,593)
Decrease in other liabilities		(23,976)
Net cash provided (used) by operating activities	6,217	(287,188)
Cash flows from investing activities
Acquisition, net of cash acquired		(22,430,749)
Principal collected on ESOP loan	118,694	116,819
Loans made, net of principal repayments	46,251	153,313
Proceeds from maturing and called securities available for sale, including principal pay downs		1,000,000
Purchase of investment securities available-for-sale		(2,026,900)
Net cash provided (used) by investing activities	164,945	(23,187,517)
Cash flows from financing activities
Dividend from Bank subsidiary		24,000,000
Dividend to Bank subsidiary		(3,000,000)
Issuance of restricted stock		20
Redemption of restricted stock	(35)	(45)
Net cash (used) provided by financing activities	(35)	20,999,975
Net increase (decrease) in cash and cash equivalents	171,127	(2,474,730)
Cash and cash equivalents at beginning of period	3,250,700	5,725,430
Cash and cash equivalents at end of period	$ 3,421,827	$ 3,250,700