Capital Structure - Schedule of Changes in Stockholders' Deficit and Equity (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Capital Structure [Line Items]
Beginning Balances			$ (6,928)
Net income	611	467	1,697	1,442
Repurchase of common stock			(750)
Other comprehensive income	(7)	52	51	83
Distributions			(325)
Share-based benefit plans			242
Other			(5)
Ending Balances	(6,018)		(6,018)
Repurchase of common stock, Shares			14,554,628
Common Stock [Member]
Capital Structure [Line Items]
Beginning Balances			4
Net income			0
Repurchase of common stock			0
Other comprehensive income			0
Distributions			0
Share-based benefit plans			0
Other			0
Ending Balances	4		4
Beginning Balances, Shares			439,604
Repurchase of common stock, Shares			(14,555)
Share-based benefit plans, Shares			8,330
Ending Balances, Shares	433,379		433,379
Capital in Excess of Par Value [Member]
Capital Structure [Line Items]
Beginning Balances			1,386
Net income			0
Repurchase of common stock			(750)
Other comprehensive income			0
Distributions			0
Share-based benefit plans			242
Other			(6)
Ending Balances	872		872
Accumulated Other Comprehensive Loss [Member]
Capital Structure [Line Items]
Beginning Balances			(257)
Net income			0
Repurchase of common stock			0
Other comprehensive income			51
Distributions			0
Share-based benefit plans			0
Other			0
Ending Balances	(206)		(206)
Retained Deficit [Member]
Capital Structure [Line Items]
Beginning Balances			(9,403)
Net income			1,348
Repurchase of common stock			0
Other comprehensive income			0
Distributions			0
Share-based benefit plans			0
Other			1
Ending Balances	(8,054)		(8,054)
Equity Attributable to Noncontrolling Interests [Member]
Capital Structure [Line Items]
Beginning Balances			1,342
Net income			349
Repurchase of common stock			0
Other comprehensive income			0
Distributions			(325)
Share-based benefit plans			0
Other			0
Ending Balances	$ 1,366		$ 1,366