Summary Of Significant Accounting Policies (Narrative) (Details) $ in Millions	12 Months Ended
Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($) Client	Jun. 30, 2014 USD ($) Client
Investigator fees	$ 397.1	$ 461.0	$ 523.1
Number of counterparties in derivative contracts	7
Capitalized software costs, net	$ 174.8	162.9
Capitalized software expense	43.2	38.7	34.2
Capitalized software future amortization expense, 2017	51.6
Capitalized software future amortization expense, 2018	46.6
Capitalized software future amortization expense, 2019	36.4
Capitalized software future amortization expense, 2020	23.4
Capitalized software future amortization expense, 2021	10.1
Research and development expense	19.2	24.0	26.9
Transaction (losses) gains	$ (0.5)	$ 7.0	$ (3.5)
Office Furniture, Fixtures And Equipment [Member]
Estimated useful lives, years	5 years
Minimum [Member]
Marketable Securities Maturity Period	90 days
Intangible asset, useful life	1 year
Minimum [Member] \| Computer Software And Hardware [Member]
Estimated useful lives, years	3 years
Maximum [Member]
Marketable Securities Maturity Period	1 year
Intangible asset, useful life	15 years
Maximum [Member] \| Computer Software And Hardware [Member]
Estimated useful lives, years	8 years
Sales Revenue, Services, Net [Member]
Concentration risk, number of clients \| Client			2
Sales Revenue, Services, Net [Member] \| Customer A [Member]
Concentration risk, percentage	13.00%	14.00%	16.00%
Sales Revenue, Services, Net [Member] \| Customer B [Member]
Concentration risk, percentage			11.00%
Accounts Receivable [Member]
Concentration risk, number of clients \| Client		2
Accounts Receivable [Member] \| Customer A [Member]
Concentration risk, percentage	12.00%	12.00%
Accounts Receivable [Member] \| Customer B [Member]
Concentration risk, percentage		11.00%

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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