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Business Segments (Details4) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Long-Lived Assets [Line Items]
Sales	$ 658.3	$ 598.0	$ 770.3	$ 955.5	$ 1,018.6	$ 1,018.7	$ 1,080.4	$ 1,004.8	$ 2,982.1	$ 4,122.5	$ 4,046.6
Identifiable Assets	$ 4,034.9				$ 5,634.6				$ 4,034.9	$ 5,634.6	$ 5,501.8
Percent of total	100.00%				100.00%				100.00%	100.00%	100.00%
United States
Long-Lived Assets [Line Items]
Sales									$ 1,809.1	$ 2,454.6	$ 2,348.1
Identifiable Assets	$ 3,356.8				$ 4,956.4				$ 3,356.8	$ 4,956.4	$ 4,859.1
Percent of total	83.00%				88.00%				83.00%	88.00%	88.00%
China
Long-Lived Assets [Line Items]
Sales									$ 315.5	$ 355.6	$ 320.0
Identifiable Assets	$ 325.5				$ 288.1				$ 325.5	$ 288.1	$ 287.3
Percent of total	8.00%				5.00%				8.00%	5.00%	5.00%
UNITED KINGDOM
Long-Lived Assets [Line Items]
Sales									$ 126.5	$ 173.8	$ 242.1
Identifiable Assets	$ 122.4				$ 141.3				$ 122.4	$ 141.3	$ 136.7
Percent of total	3.00%				3.00%				3.00%	3.00%	3.00%
Germany
Long-Lived Assets [Line Items]
Sales									$ 125.4	$ 219.3	$ 247.2
France
Long-Lived Assets [Line Items]
Sales									85.0	155.5	183.6
JAPAN
Long-Lived Assets [Line Items]
Sales									86.2	147.7	214.9
Other [Member]
Long-Lived Assets [Line Items]
Identifiable Assets	$ 230.2				$ 248.8				$ 230.2	$ 248.8	$ 218.7
Percent of total	6.00%				4.00%				6.00%	4.00%	4.00%

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