Note 15 - Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details) $ in Thousands	6 Months Ended
Feb. 28, 2019 USD ($)
Unrecognized income tax benefits	$ 9,223
Additions based on tax positions related to the current year	1,493
Additions for tax positions of prior years	270
Unrecognized income tax benefits	$ 10,986

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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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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