Business Combinations (Preliminary Estimated Fair Value Of Assets Acquired And Liabilities Assumed) (Details) (USD $) In Millions, unless otherwise specified	May 06, 2011 Engenio External Storage Systems Business [Member]	Apr. 29, 2011 Akorri And Bycast [Member]
Business Acquisition [Line Items]
Current assets	$ 49.8
Property and equipment	33.3
Identified intangible assets	272.1	45.6
Goodwill	143.7	80.5
Other assets	9.3
Total assets acquired	508.2
Current liabilities	(20.9)
Other liabilities	(7.3)
Total purchase price	$ 480.0	$ 146.1

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

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The amount of acquisition cost of a business combination allocated to assets acquired.

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The amount of acquisition cost of a business combination allocated to current assets.

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The amount of acquisition cost of a business combination allocated to current liabilities of the acquired entity.

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Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

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Amount of acquisition cost of a business combination allocated to other noncurrent assets not separately disclosed.

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The amount of acquisition cost of a business combination allocated to property, plant and equipment to be used in ongoing operations.

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