Business Combination, Intangible Assets Acquired (Details) (Business Acquisitions - 2011 [Member], USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2011 Year	Mar. 31, 2011
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, amount		$ 28.4
Existing or Core Technology [Member]
Business Acquisition [Line Items]
Acquired finite-lived intangible asset, estimated useful life (in years)	10
Acquired finite-lived intangible assets, amount		21.9
Support Agreements and Related Relationships [Member]
Business Acquisition [Line Items]
Acquired finite-lived intangible asset, estimated useful life (in years)	4
Acquired finite-lived intangible assets, amount		5.1
Patents [Member]
Business Acquisition [Line Items]
Acquired finite-lived intangible asset, estimated useful life (in years)	5
Acquired finite-lived intangible assets, amount		$ 1.4