Segment Information - Segment Information by Product (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Revenue from External Customer [Line Items]
Net revenue	$ 270.6	$ 323.0	$ 552.3	$ 639.5
Traditional Storage
Revenue from External Customer [Line Items]
Net revenue	183.0	227.6	376.0	450.4
Traditional Storage, Optical Products
Revenue from External Customer [Line Items]
Net revenue	109.8	129.3	220.8	257.0
Traditional Storage, Magentic Products
Revenue from External Customer [Line Items]
Net revenue	69.3	85.3	146.7	167.8
Traditional Storage, Other
Revenue from External Customer [Line Items]
Net revenue	3.9	13.0	8.5	25.6
Secure and Scalable Storage
Revenue from External Customer [Line Items]
Net revenue	50.0	55.4	102.8	108.1
Audio and Video Information
Revenue from External Customer [Line Items]
Net revenue	$ 37.6	$ 40.0	$ 73.5	$ 81.0