Consolidated Statements of Operations (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Revenue	$ 777	$ 651	$ 1,541	$ 1,282
Operating expenses:
Cost of products	620	527	1,236	1,044
Warehousing, selling and administrative	139	138	280	273
Operating profit (loss)	18	(14)	25	(35)
Other expense	(3)	(3)	(7)	(5)
Income (loss) before income taxes	15	(17)	18	(40)
Income tax provision (benefit)	1	0	2	0
Net income (loss)	$ 14	$ (17)	$ 16	$ (40)
Earnings (loss) per share:
Basic earnings (loss) per common share	$ 0.12	$ (0.16)	$ 0.15	$ (0.37)
Diluted earnings (loss) per common share	$ 0.12	$ (0.16)	$ 0.15	$ (0.37)
Weighted-average common shares outstanding, basic	108,278,356	107,689,554	108,177,100	107,635,122
Weighted-average common shares outstanding, diluted	108,476,988	107,689,554	108,325,437	107,635,122