Note 6 - Income Taxes - Reconciliation of the Statutory Federal Income Tax Rate to Qualstar's Effective Rate (Details)	6 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Jun. 30, 2015
Statutory federal income tax benefit	(34.00%)	(34.00%)	(34.00%)	(34.00%)
State income taxes, net of federal income tax benefit	(10.90%)	8.70%	(10.90%)	(4.30%)
Foreign income taxes, net of federal income tax benefit	0.70%	(1.30%)	0.70%	1.80%
Engineering credits	(2.50%)	(5.20%)	(2.50%)	(8.20%)
Valuation allowance	48.30%	26.20%	48.30%	43.30%
Other	(0.50%)	5.60%	(0.50%)	1.40%
Effective federal income tax rate	1.10%	0.00%	1.10%	0.00%