Components of Equity (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Stockholders Equity Note [Line Items]
Beginning Balance	$ 6,326	$ 7,325
Net loss	(152)	(3)
Net loss	(152)	(3)
Issuance of common stock for comprehensive stock plans, net	(4)	(5)
Repurchase of common stock		(147)
Dividends declared on common stock		(141)
Changes in ownership and other	(17)	57
Other comprehensive income/(loss)	(3)	(16)
Ending Balance	6,150	7,070
Common Stock
Stockholders Equity Note [Line Items]
Beginning Balance	7	7
Ending Balance	7	7
Additional Paid-in Capital
Stockholders Equity Note [Line Items]
Beginning Balance	7,568	7,675
Issuance of common stock for comprehensive stock plans, net	(4)	(5)
Repurchase of common stock		(147)
Changes in ownership and other	(17)	57
Ending Balance	7,547	7,580
Accumulated Other Comprehensive Income (Loss)
Stockholders Equity Note [Line Items]
Beginning Balance	(74)	(56)
Other comprehensive income/(loss)	(3)	(16)
Ending Balance	(77)	(72)
Retained Earnings / (Deficit)
Stockholders Equity Note [Line Items]
Beginning Balance	(1,180)	(307)
Net loss	(152)	(3)
Dividends declared on common stock		(141)
Ending Balance	(1,332)	(451)
Non-redeemable, non-controlling interests
Stockholders Equity Note [Line Items]
Beginning Balance	5	6
Ending Balance	5	6
Redeemable, non-controlling interests
Stockholders Equity Note [Line Items]
Beginning Balance	108	142
Net loss	(1)
Distributions to non-controlling interests		(2)
Changes in ownership and other	17	(56)
Ending Balance	$ 124	$ 84