Note 10 - Goodwill - Changes in the Carrying Amount of Goodwill by Segment (Details) - USD ($) $ in Thousands	12 Months Ended
Aug. 31, 2018	Aug. 31, 2017
Beginning Balance	$ 707,560	$ 452,915
Acquisitions and other adjustments	2,202	235,402
Foreign currency translations	(3,525)	19,243
Ending Balance	701,833	707,560
Acquisitions and other adjustments	(2,202)	(235,402)
UNITED STATES
Beginning Balance	386,835	367,480
Acquisitions and other adjustments	640	19,355
Foreign currency translations
Ending Balance	386,195	386,835
Acquisitions and other adjustments	(640)	(19,355)
Europe [Member]
Beginning Balance	317,759	82,280
Acquisitions and other adjustments	1,562	216,047
Foreign currency translations	(3,503)	19,432
Ending Balance	312,694	317,759
Acquisitions and other adjustments	(1,562)	(216,047)
Asia Pacific [Member]
Beginning Balance	2,966	3,155
Acquisitions and other adjustments
Foreign currency translations	(22)	(189)
Ending Balance	2,944	2,966
Acquisitions and other adjustments

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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