Goodwill and Other Intangible Assets (Tables)

3 Months Ended

Mar. 31, 2013

Goodwill and Other Intangible Assets [Abstract]

Acquired intangible assets subject to amortization

   Acquired intangible assets subject to amortization as of March 31, 2013 and December 31, 2012 were as follows:

	March 31, 2013			December 31, 2012
(millions of dollars)		Gross Carrying Amount	Accumulated Amortization		Gross Carrying Amount	Accumulated Amortization
Patents and trademarks	$	6.0	3.5		6.0	3.4
Customer lists		2.9	2.4		2.9	2.4
	$	8.9	5.9		8.9	5.8