Consolidated Statements of Operations (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Revenue	$ 822	$ 697	$ 2,363	$ 1,979
Operating expenses:
Cost of products	654	562	1,890	1,606
Warehousing, selling and administrative	142	141	422	414
Operating profit (loss)	26	(6)	51	(41)
Other expense	(4)	(3)	(11)	(8)
Income (loss) before income taxes	22	(9)	40	(49)
Income tax provision (benefit)	2	0	4	0
Net income (loss)	$ 20	$ (9)	$ 36	$ (49)
Earnings (loss) per share:
Basic earnings (loss) per common share	$ 0.18	$ (0.08)	$ 0.33	$ (0.45)
Diluted earnings (loss) per common share	$ 0.18	$ (0.08)	$ 0.33	$ (0.45)
Weighted-average common shares outstanding, basic	108,402,136	107,752,427	108,252,926	107,695,277
Weighted-average common shares outstanding, diluted	109,045,507	107,752,427	108,566,274	107,695,277