Segment Information - Schedule of Segment Reporting Information, by Segment (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Information [Line Items]
Interest expense	$ 149	$ 86	$ 431	$ 254
Operating Segments
Segment Reporting Information [Line Items]
Interest income	7	5	20	16
Interest expense	$ 14	$ 8	$ 40	$ 20