Pension and Postretirement Plans (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			3 Months Ended	12 Months Ended	3 Months Ended
	Mar. 31, 2013 U.S. Pension	Mar. 31, 2012 U.S. Pension	Dec. 31, 2013 U.S. Pension	Mar. 31, 2012 U.S. Pension Nalco	Dec. 31, 2012 U.S. Pension Nalco	Mar. 31, 2013 International Pension	Mar. 31, 2012 International Pension	Mar. 31, 2013 U.S. Postretirement Health Care	Mar. 31, 2012 U.S. Postretirement Health Care
Net periodic benefit costs
Service cost	$ 17.1	$ 12.6				$ 9.1	$ 7.3	$ 1.5	$ 1.3
Interest cost on benefit obligation	21.2	22.3				11.9	11.9	2.7	3.2
Expected return on plan assets	(32.5)	(31.8)				(11.8)	(10.5)	(0.3)	(0.3)
Recognition of net actuarial loss	15.6	11.3				2.9	1.0	0.2	0.1
Amortization of prior service benefit	(1.7)	(1.0)				(0.1)	(0.1)	(0.1)
Total expense	19.7	13.4				12.0	9.6	4.0	4.3
Other Pension Plan Information
Required contributions to defined benefit plan in current fiscal year					38
Contributions to plan	1			8	180	13		5
Contributions anticipated to be made during 2013	$ 9		$ 0			$ 37		$ 15