Corporate Investments And Funds Held For Clients (Corporate Investments And Funds Held For Clients) (Details) (USD $) In Millions	Jun. 30, 2011	Jun. 30, 2010
Money market securities and other cash equivalents - amortized cost	$ 9,731.8	$ 5,091.1
Money market securities and other cash equivalents - fair value	9,731.8	5,091.1
Available-for-sale securities - amortized cost	16,356.6	14,806.1
Available-for-sale securities - gross unrealized gains	605.5	721.1
Available-for-sale securities - gross unrealized losses	(34.6)	(10.2)
Available-for-sale securities - fair value	16,927.5	15,517.0
Total corporate investments and funds held for clients - amortized cost	26,088.4	19,897.2
Total corporate investments and funds held for clients - gross unrealized gains	605.5	721.1
Total corporate investments and funds held for clients - gross unrealized losses	(34.6)	(10.2)
Total corporate investments and funds held for clients - fair value	26,659.3	20,608.1
U.S. Treasury And Direct Obligations Of U.S. Government Agencies [Member]
Available-for-sale securities - amortized cost	6,558.2	5,631.0
Available-for-sale securities - gross unrealized gains	213.0	280.7
Available-for-sale securities - gross unrealized losses	(12.1)	(0.2)
Available-for-sale securities - fair value	6,759.1	5,911.5
Corporate Bonds [Member]
Available-for-sale securities - amortized cost	5,908.6	5,080.7
Available-for-sale securities - gross unrealized gains	234.9	261.2
Available-for-sale securities - gross unrealized losses	(16.9)	(9.0)
Available-for-sale securities - fair value	6,126.6	5,332.9
Asset-Backed Securities [Member]
Available-for-sale securities - amortized cost	422.4	923.5
Available-for-sale securities - gross unrealized gains	25.4	45.3
Available-for-sale securities - fair value	447.8	968.8
Commercial Mortgage-Backed Securities [Member]
Available-for-sale securities - amortized cost	476.6	682.3
Available-for-sale securities - gross unrealized gains	15.9	25.1
Available-for-sale securities - fair value	492.5	707.4
Municipal Bonds [Member]
Available-for-sale securities - amortized cost	493.7	446.3
Available-for-sale securities - gross unrealized gains	23.1	23.1
Available-for-sale securities - gross unrealized losses	(0.6)
Available-for-sale securities - fair value	516.2	469.4
Canadian Government Obligations And Canadian Government Agency Obligations [Member]
Available-for-sale securities - amortized cost	1,082.0	998.6
Available-for-sale securities - gross unrealized gains	20.8	33.9
Available-for-sale securities - gross unrealized losses	(1.3)
Available-for-sale securities - fair value	1,101.5	1,032.5
Other Securities [Member]
Available-for-sale securities - amortized cost	1,415.1	1,043.7
Available-for-sale securities - gross unrealized gains	72.4	51.8
Available-for-sale securities - gross unrealized losses	(3.7)	(1.0)
Available-for-sale securities - fair value	$ 1,483.8	$ 1,094.5

Money market securities and other cash equivalents - amortized cost

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Total corporate investments and funds held for clients - amortized cost

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Total corporate investments and funds held for clients - fair value

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Total corporate investments and funds held for clients - gross unrealized gains

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Total corporate investments and funds held for clients - gross unrealized losses

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS115-1/124-1
-Paragraph 7
-Footnote 2
-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 Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 19
-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 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-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
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6379932&loc=d3e22054-111558

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Available-for-Sale Securities
-URI http://asc.fasb.org/extlink&oid=6505594

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This item represents the gross unrealized gains for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 22
-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 Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 13, 19
-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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27161-111563

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Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash equivalents may be reported as cash equivalents, while legally restricted equivalents held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular equivalents are not generally reported as part of unrestricted cash equivalents.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 8, 9
-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 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 1
-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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