Financial Instruments And Fair Value Measurements (Contractual Maturities Of Investments) (Details) (USD $) In Thousands	Sep. 30, 2011
Financial Instruments And Fair Value Measurements [Abstract]
Due within one year, Amortized Cost Basis	$ 102,875
Due between 1 -2 years, Amortized Cost Basis	3,629
Due after 10 years - auction rate securities, Amortized Cost Basis	57,625
Total short-term and long-term investments, Amortized Cost Basis	164,129
Due within one year, Aggregate Fair Value	102,875
Due between 1 -2 years, Aggregate Fair Value	3,629
Due after 10 years - auction rate securities, Aggregate Fair Value	39,853
Total short-term and long-term investments, Aggregate Fair Value	$ 146,357

For an unclassified balance sheet, total of debt securities categorized neither as held-to-maturity nor trading.

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