Note 13 - Stock Option and Retirement Plans - Changes to the Current Estimate of the Vesting Percentage and Related Expense (Details) - Performance Shares [Member] - BI-SAM Technologies [Member] $ in Thousands	6 Months Ended
	Feb. 28, 2019 USD ($)
Share-based Compensation Award, Tranche One [Member]
Cumulative Catch-up Adjustment		[1]
Remaining Expense to be Recognized
Share-based Compensation Award, Tranche Two [Member]
Cumulative Catch-up Adjustment	2,369	[1]
Remaining Expense to be Recognized	4,738
Share-based Compensation Award, Tranche Three [Member]
Cumulative Catch-up Adjustment	2,665	[1]
Remaining Expense to be Recognized	5,331
Share-based Compensation Award, Tranche Four [Member]
Cumulative Catch-up Adjustment	2,961	[1]
Remaining Expense to be Recognized	$ 5,923

[1] Amounts represent the cumulative catch-up adjustment to be recorded if there were a change in the vesting percentage as of February 28, 2019.