Corporate Investments And Funds Held For Clients (Corporate Investments And Funds Held For Clients) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Jun. 30, 2011
Schedule of Available-for-sale Securities [Line Items]
Money market securities and other cash equivalents - Amortized Cost	$ 7,654.0	$ 9,731.8
Money market securities and other cash equivalents - Fair Value	7,654.0	9,731.8
Total available-for-sale securities - Amortized Cost	16,464.3	16,356.6
Total available-for-sale securities - Gross Unrealized Gains	698.2	605.5
Total available-for-sale securities - Gross Unrealized Losses	(13.1)	(34.6)
Total available-for-sale securities - Fair Value	17,149.4	16,927.5
Total corporate investments and funds held for clients - Amortized Cost	24,118.3	26,088.4
Total corporate investments and funds held for clients - Gross Unrealized Gains	698.2	605.5
Total corporate investments and funds held for clients - Gross Unrealized Losses	(13.1)	(34.6)
Total corporate investments and funds held for clients - Fair Value	24,803.4	26,659.3
U.S. Treasury And Direct Obligations Of U.S. Government Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Total available-for-sale securities - Amortized Cost	6,539.1	6,558.2
Total available-for-sale securities - Gross Unrealized Gains	271.6	213.0
Total available-for-sale securities - Gross Unrealized Losses	(0.1)	(12.1)
Total available-for-sale securities - Fair Value	6,810.6	6,759.1
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Total available-for-sale securities - Amortized Cost	6,249.0	5,908.6
Total available-for-sale securities - Gross Unrealized Gains	245.8	234.9
Total available-for-sale securities - Gross Unrealized Losses	(10.9)	(16.9)
Total available-for-sale securities - Fair Value	6,483.9	6,126.6
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Total available-for-sale securities - Amortized Cost	357.9	422.4
Total available-for-sale securities - Gross Unrealized Gains	18.8	25.4
Total available-for-sale securities - Fair Value	376.7	447.8
Commercial Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Total available-for-sale securities - Amortized Cost	374.6	476.6
Total available-for-sale securities - Gross Unrealized Gains	13.4	15.9
Total available-for-sale securities - Fair Value	388.0	492.5
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Total available-for-sale securities - Amortized Cost	494.7	493.7
Total available-for-sale securities - Gross Unrealized Gains	33.4	23.1
Total available-for-sale securities - Gross Unrealized Losses		(0.6)
Total available-for-sale securities - Fair Value	528.1	516.2
Canadian Government Obligations And Canadian Government Agency Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Total available-for-sale securities - Amortized Cost	996.5	1,082.0
Total available-for-sale securities - Gross Unrealized Gains	31.1	20.8
Total available-for-sale securities - Gross Unrealized Losses	(0.1)	(1.3)
Total available-for-sale securities - Fair Value	1,027.5	1,101.5
Other Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Total available-for-sale securities - Amortized Cost	1,452.5	1,415.1
Total available-for-sale securities - Gross Unrealized Gains	84.1	72.4
Total available-for-sale securities - Gross Unrealized Losses	(2.0)	(3.7)
Total available-for-sale securities - Fair Value	$ 1,534.6	$ 1,483.8

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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- Definition

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.

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- Definition

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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-Paragraph 12

-Subparagraph b

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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.

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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.

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-Publisher SEC

-Name Regulation S-X (SX)

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