Condensed Consolidated Statements of Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Net sales	$ 851	$ 795	$ 2,517	$ 2,373
Cost of products sold	699	633	2,042	1,884
Gross profit	152	162	475	489
Selling and administrative expenses	83	71	285	219
Operating profit	69	91	190	270
Income from equity method investments	12	15	33	42
Interest expense	(14)	(15)	(43)	(54)
Interest income	2	1	5	2
Loss on extinguishment of debt	0	0	0	(22)
Other income, net	4	1	4	5
Income from continuing operations before income taxes	73	93	189	243
Income tax expense	(15)	(27)	(37)	(76)
Income from continuing operations	58	66	152	167
Income (loss) from discontinued operations, net of tax	1	0	2	(10)
Net income	$ 59	$ 66	$ 154	$ 157
Earnings per average common share - basic:
Income from continuing operations (in dollars per share)	$ 0.42	$ 0.47	$ 1.08	$ 1.16
Income (loss) from discontinued operations (in dollars per share)	0.00	0.00	0.01	(0.07)
Net income (in dollars per share)	0.42	0.47	1.09	1.09
Earnings per average common share - diluted:
Income from continuing operations (in dollars per share)	0.41	0.46	1.06	1.14
Income (loss) from discontinued operations (in dollars per share)	0.00	0.00	0.01	(0.07)
Net income (in dollars per share)	$ 0.41	$ 0.46	$ 1.07	$ 1.07
Average common shares (in shares)	139,943,168	142,103,717	140,328,443	145,054,965
Dilutive awards under long-term incentive plan (in shares)	2,902,210	2,389,428	2,255,947	2,312,816
Deferred shares for non-employee directors (in shares)	23,948	188,546	0	216,242
Average diluted common shares (in shares)	142,869,326	144,681,691	142,584,390	147,584,023
Cash dividend declared per share (in dollars per share)	$ 0.50	$ 0	$ 0.50	$ 0