Comprehensive Income And Accumulated Other Comprehensive Loss - Changes in Components of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			$ 1,569
Ending balance	$ 2,430		2,430
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(425)	$ (542)	(432)	$ (439)
Other comprehensive income/(loss) before reclassifications	(40)	36	(43)	(70)
Amounts reclassified from AOCL	3	2	13	5
Other comprehensive income/(loss)	(37)	38	(30)	(65)
Ending balance	(462)	(504)	(462)	(504)
Pension and Other Retirement Benefits
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(108)	(84)	(118)	(92)
Other comprehensive income/(loss) before reclassifications	3	(7)	3	(1)
Amounts reclassified from AOCL	2	2	12	4
Other comprehensive income/(loss)	5	(5)	15	3
Ending balance	(103)	(89)	(103)	(89)
Cash Flow Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(48)	(49)	(49)	0
Other comprehensive income/(loss) before reclassifications	0	0	0	(50)
Amounts reclassified from AOCL	1	0	2	1
Other comprehensive income/(loss)	1	0	2	(49)
Ending balance	(47)	(49)	(47)	(49)
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(152)	(479)	(45)	(401)
Other comprehensive income/(loss) before reclassifications	(116)	186	(223)	108
Amounts reclassified from AOCL	0	0	0	0
Other comprehensive income/(loss)	(116)	186	(223)	108
Ending balance	(268)	(293)	(268)	(293)
Net Investment Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(117)	70	(220)	54
Other comprehensive income/(loss) before reclassifications	73	(143)	177	(127)
Amounts reclassified from AOCL	0	0	(1)	0
Other comprehensive income/(loss)	73	(143)	176	(127)
Ending balance	$ (44)	$ (73)	$ (44)	$ (73)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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