Organization And Summary Of Significant Accounting Policies (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Jul. 31, 2011	Jul. 31, 2010	Apr. 30, 2011
Organization And Summary Of Significant Accounting Policies
Number of offices	76
Number of countries	36
Investments in affiliated companies maximum	50.00%		50.00%
Restricted cash	$ 10.0		$ 10.0
Other-than-temporary impairment	0	0
Impairment of goodwill	0
Impairment of intangible assets			0
Estimated useful life, minimum (years)	5
Estimated useful life, maximum (years)	24
Performance related bonus expenses	32.7	34.0
Increase (decrease) in performance related bonus expenses	(1.2)	(2.0)
Performance related bonus after reduction in the previous year estimate	$ 31.5	$ 32.0

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Organization and summary of significant accounting policies.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill. Goodwill is assessed at least annually for impairment.

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Cash and equivalents whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements.

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