Corporate Investments And Funds Held For Clients (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Dec. 31, 2011	Dec. 31, 2011 years	Jun. 30, 2011
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	$ 17,149.4	$ 17,149.4	$ 16,927.5
Client funds obligations	22,690.2	22,690.2	24,591.1
Available-for-sale securities, continuous unrealized loss position, aggregate losses	13.1	13.1
Percentage of the available-for-sale securities were rated AAA or AA		87.00%
Client funds investments with original maturities		90 days or less
Earliest non-callable debt maturity date		January 2012
Latest non-callable debt maturity date		December 2021
Available-for-sale securities, gross unrealized gain (loss)	(5.8)	(5.8)
Impairment losses on available -for-sale securities	5.8	5.8
Required to sell securities unrealized loss		13.1
Length of shortest cash flow of residential mortgages used as collateral for the Company's mortgage-backed securities (in years)		15
Length of longest cash flow of residential mortgages used as collateral for the Company's mortgage-backed securities (in years)		30
Federal Home Loan Banks [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	3,998.7	3,998.7	3,886.5
Federal Farm Credit Banks [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	1,010.2	1,010.2	914.0
Federal National Mortgage Association ("Fannie Mae") [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	639.0	639.0	702.4
Federal Home Loan Mortgage Corporation ("Freddie Mac") [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	643.3	643.3	759.1
Fixed Rate Credit Card [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	210.2	210.2	220.5
Rate Reduction [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	153.1	153.1	196.9
Asset-Backed Auto Loan Receivables [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	13.1	13.1	30.0
Residential Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	143.5	143.5	146.5
Canadian Provincial Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	554.9	554.9	494.3
Corporate Bonds Backed By Federal Deposit Insurance Corporation's Temporary Liquidity Guarantee Program [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	62.5	62.5	129.1
Sovereign Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	346.0	346.0	328.8
Supranational Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	$ 404.1	$ 404.1	$ 360.1

Client funds investments, maturity period.

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Represent the Company's contractual obligations to remit funds to satisfy clients' payroll and tax payment obligations and are recorded on the Balance Sheet at the time that the Company impounds funds from clients.

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Earliest non-callable debt maturity date

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Latest non-callable debt maturity date

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Length of longest cash flow of residential mortgages used as collateral for the Company's mortgage-backed securities (in years).

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Length of shortest cash flow of residential mortgages used as collateral for the Company's mortgage-backed securities (in years).

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Percentage of the available-for-sale securities were rated AAA or AA

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This item represents the excess of amortized cost basis over fair value of securities in a loss position and which are categorized neither as held-to-maturity nor trading securities.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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The net amount of gross unrealized gains (losses) for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

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The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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The increase (decrease), resulting in a loss, in the difference between the fair value and the carrying value, or in the comparative fair values, of securities held at each balance sheet date, that was included in earnings for the period.

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