Note 3 - Acquisitions - Allocation of Preliminary Purchase Price (Details) - USD ($)		Mar. 31, 2017	May 13, 2016	Mar. 31, 2016	Sep. 11, 2015	Mar. 31, 2015
Goodwill		$ 8,563,530		$ 6,767,811		$ 2,664,432
Fraternity Community Bancorp, Inc. [Member]
Interest bearing deposits			$ 108,746,923
Borrowings			15,793,537
Other liabilities			4,023,914
Total identifiable liabilities			129,806,561
Net tangible assets acquired			23,585,608
Total identifiable liabilities			129,806,561
Net tangible assets acquired			23,585,608
Definite lived intangible assets acquired			242,020
Goodwill			1,877,243
Net intangible assets acquired			2,119,263
Total cash consideration			25,704,871
Cash and cash equivalents			15,196,058
Investment securities available for sale			17,570,712
FHLB Bank Stock			782,600
Loans			108,804,183
Allowance For Loan Loss
Premises and equipment			769,806
Bank-Owned Life Insurance			5,058,041
Deferred income taxes			2,333,104
Other assets			2,877,665
Total identifiable assets			153,392,169
Non-interest bearing deposits			1,242,187
Net intangible assets acquired			2,119,263
Total cash consideration			25,704,871
Fraternity Community Bancorp, Inc. [Member] | Carrying Amount by Acquiree [Member]
Interest bearing deposits			107,648,792
Borrowings			15,000,000
Other liabilities			4,023,914
Total identifiable liabilities			127,914,893
Net tangible assets acquired			24,326,800
Total identifiable liabilities			127,914,893
Net tangible assets acquired			24,326,800
Definite lived intangible assets acquired
Goodwill
Net intangible assets acquired
Total cash consideration			24,326,800
Cash and cash equivalents			15,196,058
Investment securities available for sale			17,570,712
FHLB Bank Stock			782,600
Loans			108,872,041
Allowance For Loan Loss			(1,550,000)
Premises and equipment			691,095
Bank-Owned Life Insurance			5,058,041
Deferred income taxes			2,743,481
Other assets			2,877,665
Total identifiable assets			152,241,693
Non-interest bearing deposits			1,242,187
Net intangible assets acquired
Total cash consideration			24,326,800
Fraternity Community Bancorp, Inc. [Member] | Fair Value Adjustments [Member]
Interest bearing deposits	[1]		1,098,131
Borrowings	[2]		793,537
Other liabilities
Total identifiable liabilities			1,891,668
Net tangible assets acquired			(741,192)
Total identifiable liabilities			1,891,668
Net tangible assets acquired			(741,192)
Definite lived intangible assets acquired			242,020
Goodwill			1,877,243
Net intangible assets acquired			2,119,263
Total cash consideration			1,378,071
Cash and cash equivalents
Investment securities available for sale
FHLB Bank Stock
Loans	[3]		(67,858)
Allowance For Loan Loss	[3]		1,550,000
Premises and equipment	[4]		78,711
Bank-Owned Life Insurance
Deferred income taxes	[5]		(410,377)
Other assets
Total identifiable assets			1,150,476
Non-interest bearing deposits
Net intangible assets acquired			2,119,263
Total cash consideration			$ 1,378,071
Fairmount Bancorp, Inc. [Member]
Interest bearing deposits					$ 52,557,297
Borrowings					10,889,147
Other liabilities					120,351
Total identifiable liabilities					64,476,464
Net tangible assets acquired					9,637,225
Total identifiable liabilities					64,476,464
Net tangible assets acquired					9,637,225
Definite lived intangible assets acquired					542,540
Goodwill					4,012,605
Net intangible assets acquired					4,555,145
Total cash consideration					14,192,370
Cash and cash equivalents					1,468,499
Certificates of deposit					4,495,597
Investment securities available for sale					9,729,405
Loans					53,577,912
Allowance For Loan Loss
Premises and equipment					2,248,590
Core Deposit Intangible
Deferred income taxes					1,561,931
Other assets					1,031,755
Total identifiable assets					74,113,689
Non-interest bearing deposits					909,669
Net intangible assets acquired					4,555,145
Total cash consideration					14,192,370
Fairmount Bancorp, Inc. [Member] | Carrying Amount by Acquiree [Member]
Interest bearing deposits					52,123,868
Borrowings					10,500,000
Other liabilities					120,351
Total identifiable liabilities					63,653,888
Net tangible assets acquired					11,870,585
Total identifiable liabilities					63,653,888
Net tangible assets acquired					11,870,585
Definite lived intangible assets acquired
Goodwill
Net intangible assets acquired
Total cash consideration					11,870,585
Cash and cash equivalents					1,468,499
Certificates of deposit					4,467,825
Investment securities available for sale					9,729,405
Loans					55,454,414
Allowance For Loan Loss					(591,070)
Premises and equipment					2,975,587
Core Deposit Intangible					22,802
Deferred income taxes					965,256
Other assets					1,031,755
Total identifiable assets					75,524,473
Non-interest bearing deposits					909,669
Net intangible assets acquired
Total cash consideration					11,870,585
Fairmount Bancorp, Inc. [Member] | Fair Value Adjustments [Member]
Interest bearing deposits	[1]				433,429
Borrowings	[2]				389,147
Other liabilities
Total identifiable liabilities					822,576
Net tangible assets acquired					(2,233,360)
Total identifiable liabilities					822,576
Net tangible assets acquired					(2,233,360)
Definite lived intangible assets acquired					542,540
Goodwill					4,012,605
Net intangible assets acquired					4,555,145
Total cash consideration					2,321,785
Cash and cash equivalents
Certificates of deposit	[6]				27,772
Investment securities available for sale
Loans	[7]				(1,876,502)
Allowance For Loan Loss	[7]				591,070
Premises and equipment	[4]				(726,997)
Core Deposit Intangible	[8]				(22,802)
Deferred income taxes	[5]				596,675
Other assets
Total identifiable assets					(1,410,784)
Non-interest bearing deposits
Net intangible assets acquired					4,555,145
Total cash consideration					$ 2,321,785

[1] Adjustment arises since the rates on interest-bearing deposits are higher than rates available on similar deposits as of the acquisition date.

[2] Adjustment reflects the fair value of Fraternity's borrowings acquired on acquisition date.

[3] Adjustment reflects the fair value adjustments based on Hamilton Bancorp's evaluation of the acquired loan portfolio and excludes the allowance for losses recorded by Fraternity Community Bancorp, Inc.

[4] Adjustment reflects the fair value adjustments based on Hamilton Bancorp's evaluation of the acquired premises and equipment.

[5] Adjustment to record deferred tax asset related to fair value adjustments at 39.45% income tax rate.

[6] Adjustment reflects marking the certificates of deposit portfolio to fair value as of the acquisition date.

[7] Adjustment reflects the fair value adjustments based on Hamilton Bancorp's evaluation of the acquired loan portfolio and excludes the allowance for losses recorded by Fairmount Bancorp, Inc.

[8] Adjustment reflects the elimination of core deposit intangible recorded by Fairmount Bancorp, Inc. from an acquisition prior.