Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Condensed Consolidated Balance Sheets
Receivables, allowance (in dollars)	$ 6.9	$ 6.0
Property, plant and equipment, accumulated depreciation (in dollars)	$ 650.3	$ 635.7
Preferred stock, par value (in dollars per share)	$ 1	$ 1
Preferred stock, Authorized shares	5,000,000	5,000,000
Preferred stock, unissued shares	5,000,000	5,000,000
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, Authorized shares	100,000,000	100,000,000
Common stock, shares issued	78,661,248	78,661,248
Common stock, shares outstanding	63,344,826	63,127,299
Treasury, shares	15,072,192	15,249,714