Note 9 - Goodwill (Details) - Changes in the Carrying Amount of Goodwill by Segment (USD $) In Thousands, unless otherwise specified	0 Months Ended	6 Months Ended
Feb. 06, 2015	Feb. 28, 2015
Goodwill [Line Items]
Balance at August 31, 2014		$ 285,608us-gaap_Goodwill
Balance at February 28, 2015		305,893us-gaap_Goodwill
Foreign currency translations		(9,339)us-gaap_GoodwillTranslationAdjustments
Code Red, Inc. [Member] \| UNITED STATES
Goodwill [Line Items]
Goodwill acquired during the period		29,624
Code Red, Inc. [Member] \| Europe [Member]
Goodwill [Line Items]
Goodwill acquired during the period		0
Code Red, Inc. [Member] \| Asia Pacific [Member]
Goodwill [Line Items]
Goodwill acquired during the period		0
Code Red, Inc. [Member]
Goodwill [Line Items]
Balance at August 31, 2014	29,600
Balance at February 28, 2015		29,624
Goodwill acquired during the period	29,600	29,624
UNITED STATES
Goodwill [Line Items]
Balance at August 31, 2014		179,434
Balance at February 28, 2015		209,058
Foreign currency translations		0
Europe [Member]
Goodwill [Line Items]
Balance at August 31, 2014		103,032
Balance at February 28, 2015		94,105
Foreign currency translations		(8,927)
Asia Pacific [Member]
Goodwill [Line Items]
Balance at August 31, 2014		3,142
Balance at February 28, 2015		2,730
Foreign currency translations		$ (412)

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Details

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- Definition

Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Details

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Namespace Prefix:
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- Details

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- Details

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Namespace Prefix:
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- Details

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