v2.3.0.15

Fair Value Measurements (Narrative) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2010	Mar. 31, 2011 Auction Rate Securities, Sold [Member]	Mar. 31, 2011 Auction Rate Securities, Repurchased [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percent amount of par value at sale		90.00%
Auction rate securities par value	$ 50.1	$ 8.1	$ 42.0

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- Definition

Other Marketable Securities Non-current Auction Rate Securities Par Value

+ Details

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- Definition

Percent amount of par value at sale

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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