Note 6 - Accumulated Other Comprehensive Income (Loss) - Components of Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands			3 Months Ended			9 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2019		Mar. 31, 2018	Mar. 31, 2019		Mar. 31, 2018
Accumulated other comprehensive income (loss), before tax			$ (1,735)		$ 110	$ (2,069)		$ 675
Unrealized holding gain (loss) on available-for-sale securities arising during the period, before tax			1,946		(1,821)	2,840		(2,348)
Amounts reclassified from accumulated other comprehensive income, before tax			(1)	[1],[2]	5	(561)	[1],[2]	(33)
Net current period other comprehensive income (loss), before tax			1,945		(1,816)	2,279		(2,381)
Accumulated other comprehensive income (loss), before tax	$ (1,706)	$ 110	210		(1,706)	210		(1,706)
Accumulated other comprehensive income (loss), tax			364		(23)	434		(230)
Unrealized holding gain (loss) on available-for-sale securities arising during the period, tax			(410)		382	(598)		562
Amounts reclassified from accumulated other comprehensive income, tax				[1],[2]	(1)	118	[1],[2]	12
Net current period other comprehensive income (loss), tax			(410)		381	(480)		574
Accumulated other comprehensive income (loss), tax, before reclassification of disproportional tax effect	344	(37)			344			344
Accumulated other comprehensive income (loss), tax, reclassification of disproportional tax effect	14	14
Accumulated other comprehensive income (loss), tax	358	(23)	(46)		358	(46)		358
Accumulated other comprehensive income (loss), net			(1,371)		87	(1,635)		445
Unrealized holding gain (loss) on available-for-sale securities arising during the period, net			1,536		(1,439)	2,242		(1,786)
Amounts reclassified from accumulated other comprehensive income, net			(1)	[1],[2]	4	(443)	[1],[2]	(21)
Other comprehensive income (loss)			1,535		(1,435)	1,799		(1,807)
Accumulated other comprehensive income (loss), net, before reclassification of disproportional tax effect	(1,362)	73			(1,362)			(1,362)
Accumulated other comprehensive income (loss), net	$ (1,348)	$ 87	$ 164		$ (1,348)	$ 164		$ (1,348)

[1] Income tax expense

[2] Securities (gains) losses, net