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Description Of The Business And Basis Of Presentation (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Jun. 30, 2011
Description Of The Business And Basis Of Presentation
Cash, cash equivalents, marketable securities and restricted cash	$ 166.2
Headcount reduction due to 2011 Plan, positions	150
Headcount reduction due to 2011 Plan, percentage of workforce	30.00%
Approximate savings resulted from reduction of positions	30.0
Potential forfeiture of cash advance	$ 20.6

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- Definition

Approximate savings resulted from reduction of positions.

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- Definition

Cash, cash equivalent, marketable securities and restricted cash.

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Description Of The Business And Basis Of Presentation [Abstract]

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- Definition

Forfeiture of cash advance.

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- Definition

The number of positions eliminated during the period as a result of restructuring activities.

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- Definition

The number of positions eliminated during the period as a percentage of total positions eliminated during the period in connection with the restructuring plan(s).

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