Goodwill and Other Intangible Assets - Changes in Goodwill and Other Intangible Assets (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2016 USD ($)
Goodwill and Other Intangible Assets [Roll Forward]
Amortizing Intangible Assets, Beginning Balance	$ 350
Amortizing Intangible Assets, Amortization expense	(49)
Amortizing Intangible Assets, Ending Balance	301
Goodwill, Beginning Balance	1,608
Goodwill, Ending Balance	1,608
Other Non-Amortizing Intangible Assets, Beginning Balance	148
Other Non-Amortizing Intangible Assets, Ending Balance	$ 148