Accumulated Other Comprehensive Income - Component of Accumulated Other Comprehensive Income (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning balance			$ 154
Other comprehensive income (loss) before reclassifications, net of tax			(11)
Amounts reclassified from accumulated other comprehensive income, net of tax			(8)
Other comprehensive income (loss), net of taxes	46	(26)	(19)	(59)
Accumulated Other Comprehensive Income (Loss), Ending balance	135		135
Derivative Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning balance			(62)
Other comprehensive income (loss) before reclassifications, net of tax			(11)
Amounts reclassified from accumulated other comprehensive income, net of tax			9
Other comprehensive income (loss), net of taxes			(2)
Accumulated Other Comprehensive Income (Loss), Ending balance	(64)		(64)
Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning balance			6
Other comprehensive income (loss) before reclassifications, net of tax			2
Amounts reclassified from accumulated other comprehensive income, net of tax			0
Other comprehensive income (loss), net of taxes			2
Accumulated Other Comprehensive Income (Loss), Ending balance	8		8
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning balance			208
Other comprehensive income (loss) before reclassifications, net of tax			(2)
Amounts reclassified from accumulated other comprehensive income, net of tax			(17)
Other comprehensive income (loss), net of taxes			(19)
Accumulated Other Comprehensive Income (Loss), Ending balance	189		189
Post - Retirement Benefit Plans [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning balance			2
Other comprehensive income (loss) before reclassifications, net of tax			0
Amounts reclassified from accumulated other comprehensive income, net of tax			0
Other comprehensive income (loss), net of taxes			0
Accumulated Other Comprehensive Income (Loss), Ending balance	$ 2		$ 2