Condensed Consolidating Financial Statements (Statements of Operations and Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Condensed Consolidating Statements of Operations
Net sales	$ 1,032.9	$ 1,030.2	$ 2,922.2	$ 3,040.4
Cost of goods sold	734.6	728.3	2,090.3	2,153.8
Gross profit	298.3	301.9	831.9	886.6
Operating Expenses:
Selling, general and administrative expenses	143.4	149.4	441.6	466.1
Losses (gains) and other expenses, net	2.2	2.7	5.3	10.0
Restructuring charges	6.1	0.5	6.5	1.9
Gain (Loss) on Disposition of Business and Related Property	(0.2)	(6.2)	(9.1)	(25.8)
Gain (Loss) on Disposition of Assets		0.3		0.3
Loss(gain) from natural disaster, net of Insurance recoveries	(7.1)	0.3	(85.4)	0.3
Income from equity method investments	(3.3)	(2.4)	(10.5)	(10.8)
Operating income	156.8	145.2	465.3	393.3
non-cash pension settlement loss	0.0	0.0	60.6	0.0
Interest expense, net	12.5	10.3	36.5	28.5
Other expense (income), net	0.6	1.1	1.7	2.4
Income from continuing operations before income taxes	143.7	133.8	366.5	362.4
Income tax benefit	29.0	25.8	71.5	77.3
Income from continuing operations	114.7	108.0	295.0	285.1
Loss from discontinued operations	0.0	0.0	(0.3)	(1.7)
Net income	114.7	108.0	294.7	283.4
Other comprehensive income (loss), net of tax	2.4	5.4	61.6	(18.2)
Comprehensive income	117.1	113.4	356.3	265.2
Eliminations [Member]
Condensed Consolidating Statements of Operations
Net sales	(56.6)	(183.9)	(177.1)	(530.6)
Cost of goods sold	(56.4)	(184.3)	(175.8)	(529.0)
Gross profit	(0.2)	0.4	(1.3)	(1.6)
Operating Expenses:
Selling, general and administrative expenses	0.0	(0.3)	0.0	(0.5)
Losses (gains) and other expenses, net	(0.1)	0.0	(0.2)	(0.3)
Restructuring charges	0.0	0.0	0.0	0.0
Gain (Loss) on Disposition of Business and Related Property	0.0	0.0	0.0	0.0
Gain (Loss) on Disposition of Assets		0.0		0.0
Loss(gain) from natural disaster, net of Insurance recoveries	0.0		0.0
Income from equity method investments	135.5	154.6	334.5	354.9
Operating income	(135.6)	(153.9)	(335.6)	(355.7)
non-cash pension settlement loss			0.0
Interest expense, net	0.0	0.0	0.0	0.0
Other expense (income), net	0.0	0.0	0.0	0.0
Income from continuing operations before income taxes	(135.6)	(153.9)	(335.6)	(355.7)
Income tax benefit	0.0	0.1	(0.3)	0.2
Income from continuing operations	(135.6)	(154.0)	(335.3)	(355.9)
Loss from discontinued operations		0.0	0.0	0.0
Net income	(135.6)	(154.0)	(335.3)	(355.9)
Other comprehensive income (loss), net of tax	0.0	0.0	0.0	0.0
Comprehensive income	(135.6)	(154.0)	(335.3)	(355.9)
Parent [Member]
Condensed Consolidating Statements of Operations
Net sales	0.0	0.0	0.0	0.0
Cost of goods sold	0.0	0.0	0.0	0.0
Gross profit	0.0	0.0	0.0	0.0
Operating Expenses:
Selling, general and administrative expenses	0.0	0.0	0.0	0.0
Losses (gains) and other expenses, net	0.2	0.2	(0.2)	1.7
Restructuring charges	0.0	0.0	0.0	0.0
Gain (Loss) on Disposition of Business and Related Property	0.0	0.0	0.0	0.0
Gain (Loss) on Disposition of Assets		0.0		0.0
Loss(gain) from natural disaster, net of Insurance recoveries	0.0		0.0
Income from equity method investments	(116.4)	(109.7)	(299.6)	(289.9)
Operating income	116.2	109.5	299.8	288.2
non-cash pension settlement loss			0.0
Interest expense, net	2.1	2.0	6.7	6.8
Other expense (income), net	0.0	0.0	0.0	0.0
Income from continuing operations before income taxes	114.1	107.5	293.1	281.4
Income tax benefit	(0.6)	(0.5)	(1.6)	(2.0)
Income from continuing operations	114.7	108.0	294.7	283.4
Loss from discontinued operations		0.0	0.0	0.0
Net income	114.7	108.0	294.7	283.4
Other comprehensive income (loss), net of tax	(0.3)	(2.5)	4.1	(11.9)
Comprehensive income	114.4	105.5	298.8	271.5
Guarantor Subsidiaries [Member]
Condensed Consolidating Statements of Operations
Net sales	950.0	930.5	2,692.1	2,704.6
Cost of goods sold	681.2	660.5	1,935.6	1,938.8
Gross profit	268.8	270.0	756.5	765.8
Operating Expenses:
Selling, general and administrative expenses	139.9	138.4	423.6	423.0
Losses (gains) and other expenses, net	1.5	1.9	4.4	2.3
Restructuring charges	6.0	0.0	6.2	0.8
Gain (Loss) on Disposition of Business and Related Property	(0.2)	(40.1)	(1.3)	(39.1)
Gain (Loss) on Disposition of Assets		1.7		1.7
Loss(gain) from natural disaster, net of Insurance recoveries	(7.1)		(85.4)
Income from equity method investments	(20.1)	(45.7)	(37.2)	(67.4)
Operating income	148.4	137.0	443.6	369.7
non-cash pension settlement loss			60.6
Interest expense, net	7.7	5.0	23.1	14.4
Other expense (income), net	0.5	0.7	1.5	2.0
Income from continuing operations before income taxes	140.2	131.3	358.4	353.3
Income tax benefit	23.0	13.3	56.6	62.6
Income from continuing operations	117.2	118.0	301.8	290.7
Loss from discontinued operations		0.0	0.0	0.0
Net income	117.2	118.0	301.8	290.7
Other comprehensive income (loss), net of tax	7.7	1.2	58.1	(7.5)
Comprehensive income	124.9	119.2	359.9	283.2
Non-Guarantor Subsidiaries [Member]
Condensed Consolidating Statements of Operations
Net sales	139.5	283.6	407.2	866.4
Cost of goods sold	109.8	252.1	330.5	744.0
Gross profit	29.7	31.5	76.7	122.4
Operating Expenses:
Selling, general and administrative expenses	3.5	11.3	18.0	43.6
Losses (gains) and other expenses, net	0.6	0.6	1.3	6.3
Restructuring charges	0.1	0.5	0.3	1.1
Gain (Loss) on Disposition of Business and Related Property	0.0	33.9	(7.8)	13.3
Gain (Loss) on Disposition of Assets		2.0		2.0
Loss(gain) from natural disaster, net of Insurance recoveries	0.0		0.0
Income from equity method investments	(2.3)	(1.6)	(8.2)	(8.4)
Operating income	27.8	52.6	57.5	91.1
non-cash pension settlement loss			0.0
Interest expense, net	2.7	3.3	6.7	7.3
Other expense (income), net	0.1	0.4	0.2	0.4
Income from continuing operations before income taxes	25.0	48.9	50.6	83.4
Income tax benefit	6.6	12.9	16.8	16.5
Income from continuing operations	18.4	36.0	33.8	66.9
Loss from discontinued operations		0.0	0.3	(1.7)
Net income	18.4	36.0	33.5	65.2
Other comprehensive income (loss), net of tax	(5.0)	6.7	(0.6)	1.2
Comprehensive income	$ 13.4	$ 42.7	$ 32.9	$ 66.4