Commitment and contingencies [Line Items].

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- Definition

Largest individual client percent of total subscriptions.

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- Definition

Non cancelable lease term period.

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- Definition

Operating leases, percentage of increase in lease area

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- Definition

Percentage of subscription from ten largest clients

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- Definition

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 4

-Article 5

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

-Publisher FASB

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-Topic 310

-SubTopic 10

-Section 50

-Paragraph 4

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.10)

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- Definition

Rental expense incurred for leased assets including furniture and equipment which has not been recognized in costs and expenses applicable to sales and revenues; for example, cost of goods sold or other operating costs and expenses.

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- Definition

Amount borrowed under the credit facility as of the balance sheet date.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Regulation S-X (SX)

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-Subparagraph (SX 210.5-02.19(b),22(b))

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- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within one year of the balance sheet date relating to leases defined as operating.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 122

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Section 50

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- Definition

The amount of square footage related to a real estate property.

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Commitments And Contingencies (Narrative) (Details) (USD $)	12 Months Ended
	Aug. 31, 2011	Aug. 31, 2010	Aug. 31, 2009
Commitment And Contingencies [Line Items]
Rentable square footage, total	724,200
Percentage of increase in leased office space	13.00%
Rental expense for operating leases	$ 32,800,000	$ 30,600,000	$ 26,700,000
Standby letters of credit issued	4,400,000
Total purchase commitments	47,800,000	45,600,000
Future minimum rental payments	25,897,000
Largest individual client percent of total subscriptions	2.00%	2.00%
Percentage of subscription from ten largest clients	16.00%	16.00%
Accounts receivable reserve	1,955,000	1,862,000
Revolving credit facility, aggregate available principal amount	12,500,000
Commitment fee, weighted average annual rate	0.125%
Piscataway, New Jersey [Member]
Commitment And Contingencies [Line Items]
Future minimum rental payments	15,800,000
Non-cancelable lease term period in years	10
France [Member]
Commitment And Contingencies [Line Items]
Future minimum rental payments	3,200,000
Non-cancelable lease term period in years	6
India [Member]
Commitment And Contingencies [Line Items]
Future minimum rental payments	2,600,000
Non-cancelable lease term period in years	5
Philippines [Member]
Commitment And Contingencies [Line Items]
Future minimum rental payments	1,300,000
Non-cancelable lease term period in years	5
Dubai, United Arab Emirates [Member]
Commitment And Contingencies [Line Items]
Future minimum rental payments	200,000
Non-cancelable lease term period in years	1
Frankfurt, Germany [Member]
Commitment And Contingencies [Line Items]
Future minimum rental payments	$ 4,500,000
Non-cancelable lease term period in years	10
Headquarters In Norwalk, Connecticut [Member]
Commitment And Contingencies [Line Items]
Rentable square footage, total	169,000