Selected Quarterly Financial Data (Unaudited) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Summary of selected quarterly financial data
Net sales	$ 125.4	$ 141.0	$ 137.6	$ 116.5	$ 113.1	$ 135.5	$ 130.6	$ 99.5	$ 520.5	$ 478.7	$ 467.7
Gross margin	24.2	27.5	27.1	21.3	21.9	25.0	24.4	17.3	100.1	88.6	85.2
Operating expenses	24.3	25.5	24.6	23.4	24.1	25.4	25.6	23.3	97.8	98.4	103.3
Goodwill impairment	1.9				0.1	0.3			1.9	0.4
Gain on disposal of capital assets		(2.4)							(2.4)		(0.4)
Operating income (loss)	(2.0)	4.4	2.5	(2.1)	(2.3)	(0.7)	(1.2)	(6.0)	2.8	(10.2)	(17.7)
Net income (loss) from continuing operations	(2.7)	3.7	1.7	(2.8)	(2.8)	(1.4)	(1.9)	(6.6)	(0.1)	(12.7)	(19.4)
Net income (loss) from discontinued operations	$ (0.1)	$ (0.1)	$ (0.1)	$ (0.1)	$ (0.1)	$ (0.3)		$ (0.1)	$ (0.4)	$ (0.5)	$ 0.5
Net income (loss) per share - Diluted
Net income (loss) from continuing operations	$ (0.12)	$ 0.15	$ 0.07	$ (0.12)	$ (0.13)	$ (0.06)	$ (0.09)	$ (0.30)		$ (0.58)	$ (0.90)
Net income (loss) from discontinued operations	$ (0.01)	$ (0.01)		$ (0.01)		$ (0.02)			$ (0.02)	$ (0.02)	$ 0.02
Net income (loss)	$ (0.13)	$ 0.14	$ 0.07	$ (0.13)	$ (0.13)	$ (0.08)	$ (0.09)	$ (0.30)	$ (0.02)	$ (0.60)	$ (0.88)