Note 17 - Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Aug. 31, 2018	Aug. 31, 2017	Aug. 31, 2016
Unrecognized income tax benefits	$ 11,484	$ 8,782	$ 6,776
Additions based on tax positions related to the current year	2,954	3,896	1,779
Additions for tax positions of prior years	531	628	1,436
Statute of limitations lapse	(3,146)	(1,822)	(1,209)
Unrecognized income tax benefits	9,223	11,484	8,782
Unrecognized income tax benefits	9,223	$ 11,484	$ 6,776
Reductions from settlements with Taxing Authorities	$ (2,600)

Amount of unrecognized tax benefits.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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