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

Business Combinations (Preliminary Estimated Fair Value Of Assets Acquired And Liabilities Assumed) (Details) (Engenio External Storage Systems Business [Member], USD $)
In Millions, unless otherwise specified

May 06, 2011

Engenio External Storage Systems Business [Member]

Current assets

$ 49.8

Property and equipment

33.3

Identified intangible assets

272.1

Goodwill

143.7

Other assets

9.3

Total assets acquired

508.2

(20.9)

(7.3)

$ 480.0

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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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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The amount of acquisition cost of a business combination allocated to noncurrent assets of the acquired entity, except for property plant and equipment, intangible assets, and goodwill.

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