Corporate Investments And Funds Held For Clients (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Sep. 30, 2011	Jun. 30, 2011
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	$ 17,249.1	$ 16,927.5
Client funds obligations	18,552.6	24,591.1
Available-for-sale securities, continuous unrealized loss position, aggregate losses	7.8
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	October 2011
Latest non-callable debt maturity date	June 2021
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	3,945.6	3,886.5
Federal Farm Credit Banks [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	929.0	914.0
Federal National Mortgage Association ("Fannie Mae") [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	695.0	702.4
Federal Home Loan Mortgage Corporation ("Freddie Mac") [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	653.0	759.1
Fixed Rate Credit Card [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	205.2	220.5
Rate Reduction [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	170.9	196.9
Asset-Backed Auto Loan Receivables [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	21.4	30.0
Residential Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	145.5	146.5
Canadian Provincial Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	548.1	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	128.3	129.1
Sovereign Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	357.8	328.8
Supranational Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities - fair value	$ 386.9	$ 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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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Name Emerging Issues Task Force (EITF)

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 12

-Subparagraph b

-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.

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

-Publisher FASB

-Name Accounting Standards Codification

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