Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Income Taxes [Line Items]
Benefit (provision) for income taxes	$ 205	$ 12	$ 38	$ 18
Discrete tax benefits (provision)			(82)	54
Cash taxes paid, net of refunds	38	23	148	143	173	195
Tax contingencies	626		626		626		407
Tax examination, proposed additional tax expense including interest and penalties			1,500
France
Income Taxes [Line Items]
Tax examination, proposed additional tax expense including interest and penalties			$ 250