Note 10 - Intangible Assets - Identifiable Intangible Assets (Details) - USD ($) $ in Thousands	Feb. 28, 2019	Aug. 31, 2018
Gross Carrying Amount	$ 247,442	$ 248,289
Accumulated Amortization	111,033	99,354
Net Carrying Amount	136,409	148,935
Data Content [Member]
Gross Carrying Amount	34,135	33,992
Accumulated Amortization	21,835	20,990
Net Carrying Amount	12,300	13,002
Customer Relationships [Member]
Gross Carrying Amount	98,148	98,882
Accumulated Amortization	32,801	29,387
Net Carrying Amount	65,347	69,495
Computer Software, Intangible Asset [Member]
Gross Carrying Amount	106,231	106,505
Accumulated Amortization	50,837	44,231
Net Carrying Amount	55,394	62,274
Noncompete Agreements [Member]
Gross Carrying Amount	4,860	4,840
Accumulated Amortization	2,815	2,381
Net Carrying Amount	2,045	2,459
Trade Names [Member]
Gross Carrying Amount	4,068	4,070
Accumulated Amortization	2,745	2,365
Net Carrying Amount	$ 1,323	$ 1,705