Segment Information (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) segment product_category	Jun. 30, 2014 USD ($)
Segment Reporting Information [Line Items]
Number of reporting segments \| segment			2
Segment Reporting Information, Profit (Loss) [Abstract]
Net revenue	$ 150.6	$ 178.6	$ 306.0	$ 357.5
Operating loss	(15.9)	(20.1)	(28.9)	(36.2)
Interest income	(0.1)	(0.1)	(0.2)	(0.2)
Interest expense	0.6	0.6	1.2	1.2
Other, net expense	0.8	0.8	1.6	1.0
Loss from continuing operations before income taxes	(17.2)	(21.4)	(31.5)	(38.2)
Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Operating loss	(5.5)	(5.3)	(8.1)	(10.0)
Corporate and Unallocated
Segment Reporting Information, Profit (Loss) [Abstract]
Operating loss	(10.4)	(14.8)	$ (20.8)	(26.2)
Consumer Storage and Accessories
Segment Reporting Information [Line Items]
Number of major product categories \| product_category			2
Segment Reporting Information, Profit (Loss) [Abstract]
Net revenue	76.3	95.1	$ 151.5	195.1
Consumer Storage and Accessories \| Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Operating loss	0.7	3.2	4.6	7.3
Consumer Storage and Accessories \| Consumer Storage Media
Segment Reporting Information, Profit (Loss) [Abstract]
Net revenue	66.6	84.5	132.6	174.0
Consumer Storage and Accessories \| Audio and Accessories
Segment Reporting Information, Profit (Loss) [Abstract]
Net revenue	9.7	10.6	$ 18.9	21.1
Tiered Storage and Security Solutions
Segment Reporting Information [Line Items]
Number of major product categories \| product_category			2
Segment Reporting Information, Profit (Loss) [Abstract]
Net revenue	74.3	83.5	$ 154.5	162.4
Tiered Storage and Security Solutions \| Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Operating loss	(6.2)	(8.5)	(12.7)	(17.3)
Tiered Storage and Security Solutions \| Commercial Storage Media
Segment Reporting Information, Profit (Loss) [Abstract]
Net revenue	45.3	54.0	93.2	105.4
Tiered Storage and Security Solutions \| Storage and Security Solutions
Segment Reporting Information, Profit (Loss) [Abstract]
Net revenue	$ 29.0	$ 29.5	$ 61.3	$ 57.0

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