Note 9 - Income Taxes (Details Textual) - USD ($)	3 Months Ended			6 Months Ended		12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent								34.00%
Deferred Income Tax Expense (Benefit)				$ 7,250,000	$ 413,000
Income Tax Expense (Benefit)	$ 7,618,000	$ 454,000		7,832,000	1,171,000
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	$ 1,097,000	$ 1,517,000		$ 1,737,000	$ 2,993,000
Effective Income Tax Rate Reconciliation, Percent	694.00%	29.90%		451.00%	39.10%
Income Tax Expense (Benefit), Before Tax Cuts and Jobs Act	$ 368,000				$ 582,000
Effective Income Tax Rate Reconciliation, Before Tax Cuts and Jobs Act, Percent	33.50%				33.50%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount, Return to Provision Adjustment	$ 34,000
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	21,000		$ 298,000
Deferred Tax Assets, Valuation Allowance	0			$ 0
Foreign Tax Authority [Member] | Secretariat of the Federal Revenue Bureau of Brazil [Member]
Unrecognized Tax Benefits	$ 1,000,000			$ 1,000,000
Scenario, Forecast [Member]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent						21.00%	28.00%