Earnings Per Share (EPS) And Dividends (Basic And Diluted Earnings Per Share Computation) (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Earnings Per Share [Abstract]
Net Income	$ 345	$ 212	$ 931	$ 598
Weighted Average Common Shares Outstanding, Basic (shares)	506	506	506	506
Effect of Stock Based Compensation Awards, Basic (shares)	0	0	0	0
Total Shares, Basic (shares)	506	506	506	506
Net Income, Basic (in dollars per share)	$ 0.68	$ 0.42	$ 1.84	$ 1.18
Weighted Average Common Shares Outstanding, Diluted (shares)	506	506	506	506
Effect of Stock Based Compensation Awards, Diluted (shares)	2	2	2	2
Total Shares, Diluted (shares)	508	508	508	508
Net Income, Diluted (in dollars per share)	$ 0.68	$ 0.42	$ 1.83	$ 1.18