Financial Instruments and Fair Value Measurements (Details Textual) (USD $)	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Financial Instruments and Fair Value Measurements (Textuals) [Abstract]
Remaining cash equivalents	$ 986,084,000	$ 938,565,000
Maturity period of cash equivalents at the time of purchase	Three months or less
Maturity period of instruments in short term investments	Three months to one year
Transfer of assets in and out of level 1, 2 and 3 measurements during the period	0
Transfer of liabilities in and out of level 1, 2 and 3 measurements during the period		0
Impairment charge recorded to Research and development expense, resulting from discontinuance of a research program within the Diagnostic Systems unit	$ 9,270,000

Financial Instruments and Fair Value Measurements.

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The maximum maturity period of liquid investments classified as cash equivalents in the consolidated balance sheet.

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The maturity period of time deposits classified as short-term investments in the consolidated balance sheet.

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Amounts of cash equivalents that are carried at cost and are not measured at fair value under the fair value measurement requirements for financial assets and liabilities.

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- Definition

The charge against earnings resulting from the aggregate write down of all assets from their carrying value to their fair value.

+ References

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This element represents [net] transfers in to and out of assets measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

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