Intangible Assets (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Amortization expense relating to all intangible assets	$ 17	$ 11
Amortization expense for remainder of the year	47
Intangible assets amortization expense, year one	56
Intangible assets amortization expense, year two	42
Intangible assets amortization expense, year three	39
Intangible assets amortization expense, year four	39
Intangible assets amortization expense, year five	$ 24