Accrued Expenses - Activity in Warranty Accrual for Product Warranty (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance, beginning of the period	$ 189	$ 254	$ 207	$ 286
Provision	32	32	109	107
Amounts charged against the accrual	(41)	(59)	(136)	(166)
Balance, end of the period	$ 180	$ 227	$ 180	$ 227