Fair Value Measurement Of Assets And Liabilities (Financial Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2011 Money Market Funds And Time Deposits [Member]	Mar. 31, 2011 Deferred Purchase Price Receivable [Member]	Mar. 31, 2011 Foreign Exchange Forward Contracts [Member]	Mar. 31, 2011 Equity Securities, Fixed Income Securities And Mutual Funds [Member]	Mar. 31, 2011 Level 1 [Member] Equity Securities, Fixed Income Securities And Mutual Funds [Member]	Mar. 31, 2011 Level 2 [Member] Money Market Funds And Time Deposits [Member]	Mar. 31, 2011 Level 2 [Member] Foreign Exchange Forward Contracts [Member]	Mar. 31, 2011 Level 2 [Member] Equity Securities, Fixed Income Securities And Mutual Funds [Member]	Mar. 31, 2011 Level 3 [Member] Deferred Purchase Price Receivable [Member]	Mar. 31, 2012 Fair Value Measurements, Recurring [Member] Money Market Funds And Time Deposits [Member]	Mar. 31, 2012 Fair Value Measurements, Recurring [Member] Deferred Purchase Price Receivable [Member]	Mar. 31, 2012 Fair Value Measurements, Recurring [Member] Foreign Exchange Forward Contracts [Member]	Mar. 31, 2012 Fair Value Measurements, Recurring [Member] Available For Sale Investments [Member]	Mar. 31, 2012 Fair Value Measurements, Recurring [Member] Equity Securities, Fixed Income Securities And Mutual Funds [Member]	Mar. 31, 2012 Fair Value Measurements, Recurring [Member] Level 1 [Member] Available For Sale Investments [Member]	Mar. 31, 2012 Fair Value Measurements, Recurring [Member] Level 1 [Member] Equity Securities, Fixed Income Securities And Mutual Funds [Member]	Mar. 31, 2012 Fair Value Measurements, Recurring [Member] Level 2 [Member] Money Market Funds And Time Deposits [Member]	Mar. 31, 2012 Fair Value Measurements, Recurring [Member] Level 2 [Member] Foreign Exchange Forward Contracts [Member]	Mar. 31, 2012 Fair Value Measurements, Recurring [Member] Level 2 [Member] Equity Securities, Fixed Income Securities And Mutual Funds [Member]	Mar. 31, 2012 Fair Value Measurements, Recurring [Member] Level 3 [Member] Deferred Purchase Price Receivable [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Total Assets	$ 375,760	$ 459,994	$ 24,071	$ 56,663	$ 2,816	$ 375,760	$ 24,071	$ 53,847	$ 459,994	$ 343,906	$ 514,895	$ 20,999	$ 5,994	$ 57,652	$ 5,994	$ 3,411	$ 343,906	$ 20,999	$ 54,241	$ 514,895
Total Liabilities			$ (6,900)				$ (6,900)					$ (8,105)						$ (8,105)