Earnings Per Share (Computation Of Basic And Diluted Earnings Per Share) (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 for basic EPS	$ 143	$ 26	$ 134	$ 30
Convertible note interest, net of tax	0	1	0	1
Net income for diluted EPS	$ 143	$ 27	$ 134	$ 31
Basic weighted average shares outstanding	105.5	105.1	105.8	105.8
Options and non-vested stock (a)	1.2	1.9	1.3	2.0
Convertible debt	0.0	4.0	0.0	4.0
Diluted weighted average shares outstanding	106.7	111.0	107.1	111.8
Basic	$ 1.36	$ 0.25	$ 1.27	$ 0.29
Diluted	$ 1.34	$ 0.24	$ 1.25	$ 0.28
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0.2		0.1