Segment, Geographic, and Market Information - Sales to Unaffiliated Customers (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Geographic information [Abstract]
Sales to unaffiliated customers shipped	$ 257.5	$ 263.5	$ 258.8	$ 232.9	$ 235.6	$ 249.2	$ 251.4	$ 231.2	$ 1,012.7	$ 967.4	$ 926.3
Operating profit from sales	19.2	(24.6)	24.9	16.3	18.0	28.5	30.4	20.9	35.8	97.8	86.0
Account receivable	213.5				202.7				213.5	202.7	204.4
Property, plant, equipment, and mineral rights and reserves	263.6				301.9				263.6	301.9	273.5
Identifiable assets	878.7				910.6				878.7	910.6	849.1
Americas [Member]
Geographic information [Abstract]
Sales to unaffiliated customers shipped									605.2	588.7	546.1
Operating profit from sales									57.5	65.2	57.7
Account receivable	109.6				109.9				109.6	109.9	112.3
Property, plant, equipment, and mineral rights and reserves	162.9				134.8				162.9	134.8	116.0
Identifiable assets	430.4				448.3				430.4	448.3	420.4
EMEA [Member]
Geographic information [Abstract]
Sales to unaffiliated customers shipped									226.4	213.3	243.1
Operating profit from sales									(41.4)	10.4	10.0
Account receivable	48.1				45.3				48.1	45.3	51.9
Property, plant, equipment, and mineral rights and reserves	43.4				112.3				43.4	112.3	108.7
Identifiable assets	274.4				303.3				274.4	303.3	289.4
Asia Pacific [Member]
Geographic information [Abstract]
Sales to unaffiliated customers shipped									181.1	165.4	137.1
Operating profit from sales									19.7	22.2	18.3
Account receivable	55.8				47.5				55.8	47.5	40.2
Property, plant, equipment, and mineral rights and reserves	57.3				54.8				57.3	54.8	48.8
Identifiable assets	$ 173.9				$ 159.0				$ 173.9	$ 159.0	$ 139.3