Note 2 - Significant Accounting Policies - Earnings Per Share, Basic and Diluted (Details) - shares	3 Months Ended		6 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2017	Jun. 30, 2017
Shares issued – beginning of period (in shares)	27,121,371		27,121,371		26,996,148	25,939,892	24,809,841	24,748,213
Shares held by subsidiaries (Note 7) (in shares)	(704,309)	(704,309)	(704,309)	(704,309)
Shares outstanding – beginning of period (in shares)	26,417,062		26,417,062		26,291,839	25,235,583	24,105,532	24,043,904
Weighted average shares issued during the period (in shares)	90,939	127,591	785,681	106,204
Diluted weighted average shares – end of period (in shares)	26,382,778	24,233,123	26,021,264	24,150,108