Quarterly Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Net revenues	$ 1,353	$ 990	$ 1,044	$ 1,278	$ 1,575	$ 753	$ 970	$ 1,111	$ 4,664	$ 4,408	$ 4,583
Cost of sales	538	337	297	413	631	253	300	342
Operating income	250	196	332	542	438	8	310	427	1,319	1,183	1,372
Net income	$ 159	$ 127	$ 212	$ 394	$ 361	$ (23)	$ 204	$ 293	$ 892	$ 835	$ 1,010
Basic earnings per common share (in dollars per share)	$ 0.22	$ 0.17	$ 0.29	$ 0.54	$ 0.49	$ (0.03)	$ 0.28	$ 0.40	$ 1.21	$ 1.14	$ 0.96
Diluted earnings per common share (in dollars per share)	$ 0.21	$ 0.17	$ 0.29	$ 0.53	$ 0.49	$ (0.03)	$ 0.28	$ 0.40	$ 1.19	$ 1.13	$ 0.95