Discontinued Operations (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended	12 Months Ended
	Dec. 31, 2011 business_units	Dec. 31, 2011 business_units	Dec. 31, 2010
Discontinued Operations and Disposal Groups [Abstract]
Number of business units not disposed		3
Net loss from business units reclassified from discontinued operations			$ 0.2
Number of business units sold	2
Number of business units classified as discontinued operations written down to estimated market value	2
Net loss on the sale	0.7
Write down included in the loss from discontinued operations, net of tax	3.0
Operating losses included in the loss from discontinued operations, net	(1.3)
Cumulative tax benefits associated with loss from discontinued operations	3.8
Assets of remaining business units classified as discontinued operations	4.7	4.7
Liabilities of remaining business units classified as discontinued operations	$ 0.7	$ 0.7