Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill reclassified as held-for-sale			$ 480
Amortization expense for other intangible assets	$ 22	$ 29	$ 72	$ 85