Nature Of Operations And Summary Of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Aug. 31, 2018	Aug. 31, 2017	Aug. 31, 2016	Aug. 31, 2015	Mar. 27, 2015
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Accretion of discount on related party receivables	$ (418)	$ (156)	$ (210)
Cash and cash equivalents	10,153	8,924	10,456	$ 16,234	$ 10,000
Costs to exit Japan publishing business		2,107
Capitalized interest expense	100	100
Goodwill, impairment loss
Capitalized curriculum development spending	3,000
Capitalized development costs	9,300	11,600
Foreign currency transaction gains (losses)	(500)	(200)	(300)
Net sales	209,758	185,256	200,055
Advertising costs	$ 6,900	6,400	6,600
Percent likelihood of being realized upon ultimate settlement	50.00%
Held Outside The US By Foreign Subsidiaries [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Cash and cash equivalents	$ 8,900
Licensee Royalty [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Net sales	10,700	10,600	14,400
Covey Trade Name [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Goodwill, impairment loss	$ 0	$ 0	$ 0
Minimum [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Capitalized development costs, amortization period	3 years
Minimum [Member] | ASU 2014-09 [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Estimate cumulative effect reduction to the opening balance of retained earnings	$ 2,000
Maximum [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Capitalized development costs, amortization period	5 years
Maximum [Member] | ASU 2014-09 [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Estimate cumulative effect reduction to the opening balance of retained earnings	$ 4,000