Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Statement of Financial Position [Abstract]
Allowances for accounts receivable	$ 12.6	$ 12.1
Preferred stock, no par value (Class I & Class II Preferred stock)	$ 0	$ 0
Preferred stock, shares authorized (Class I & Class II Preferred stock)	10,000,000	10,000,000
Preferred stock, shares issued (Class I & Class II Preferred stock)	0	0
Common stock, no par value	$ 0	$ 0
Company common stock shares authorized	200,000,000	200,000,000
Common stock, shares issued	98,375,135	98,375,135
Treasury shares	2,221,214	2,476,921