Consolidated Statements of Income (Unaudited) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income Statement [Abstract]
Revenue	$ 1,070	$ 1,113	$ 3,099	$ 3,255
Operating expenses:
Cost of products	857	907	2,485	2,655
Operating and warehousing costs	108	104	315	308
Selling, general and administrative	55	39	144	118
Operating profit	50	63	155	174
Other income (expense)	(1)	(4)	(1)
Income before income taxes	49	59	154	174
Provision for income taxes	17	20	54	61
Net income	$ 32	$ 39	$ 100	$ 113
Earnings per share:
Basic earnings per common share	$ 0.30	$ 0.37	$ 0.93	$ 1.06
Diluted earnings per common share	$ 0.30	$ 0.36	$ 0.93	$ 1.05
Weighted-average common shares outstanding, basic	107,061,639	107,053,031	107,055,932	107,053,031
Weighted-average common shares outstanding, diluted	107,625,243	107,468,868	107,548,167	107,468,868