Note 10 - Fair Value Measurements (Detail) - Financial Assets (Liabilities) Not Carried at Fair Value (USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 30, 2012	Sep. 30, 2011
Jackpot investments Carrying Value	$ 355.9	$ 387.8
Jackpot investments Fair Value	422.0	458.9
Jackpot investments Unrealized Gain (Loss)	66.1	71.1
Contracts & notes receivable Carrying Value	357.5	293.5
Contracts & notes receivable Fair Value	353.5	294.6
Contracts & notes receivable Unrealized Gain (Loss)	(4.0)	1.1
Jackpot liabilities Carrying Value	(481.0)	(508.4)
Jackpot liabilities Fair Value	(503.0)	(521.6)
Jackpot liabilities Unrealized Gain (Loss)	(22.0)	(13.2)
Debt Carrying Value	(1,726.9)	(1,553.1)
Debt Fair Value	(1,955.4)	(1,879.5)
Debt Unrealized Gain (Loss)	(228.5)	(326.4)
Fair Value, Inputs, Level 1 [Member]
Jackpot investments Fair Value	422.0	458.9
Debt Fair Value	(1,815.4)	(1,879.5)
Fair Value, Inputs, Level 2 [Member]
Debt Fair Value	(140.0)
Fair Value, Inputs, Level 3 [Member]
Contracts & notes receivable Fair Value	353.5	294.6
Jackpot liabilities Fair Value	$ (503.0)	$ (521.6)

Contracts and notes receivable carrying value

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Notes Receivable Unrealized Gain, Fair Value.

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Debt fair value

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No definition available.

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Debt unrealized gain (loss)

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Held to maturity security unrealized gain

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Other Long Term Debt Unrealized Gain, Fair Value.

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Jackpot liabilities at fair value

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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For an unclassified balance sheet, this item represents investments in debt securities which are categorized as held-to-maturity. The held-to-maturity category is for those securities that the entity has the positive intent and ability to hold until maturity.

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This item represents the aggregate fair value of investments in debt securities as of the balance sheet date and which are categorized as held-to-maturity.

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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. An amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money at a future date(s).

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Including both current and noncurrent portions, carrying amount as of the balance sheet date of other forms of debt not elsewhere specified in the taxonomy with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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