Other Comprehensive Loss - Components of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Equity [Abstract]
Unrealized gains on available-for-sale securities, beginning balances	$ 14	$ 3	$ 7
Unrealized gains (losses) on available-for-sale securities	11	11	(5)
Reclassification of stranded tax effects, unrealized gains (losses) on available-for-sale securities			1
Unrealized gains on available-for-sale securities, ending balances	25	14	3
Foreign currency translation adjustments, beginning balances	(283)	(283)	(149)
Foreign currency translation adjustments	12		(63)
Reclassification of stranded tax effects, foreign currency translation adjustments			(71)
Foreign currency translation adjustments, ending balances	(271)	(283)	(283)
Defined benefit plans, beginning balances	(187)	(148)	(168)
Defined benefit plans	(55)	(49)	34
Defined benefit plans, (income) expense reclassified into operations from other comprehensive income	22	10	16
Reclassification of stranded tax effects, defined benefit plans			(30)
Defined benefit plans, ending balances	(220)	(187)	(148)
Change in fair value of derivative instruments, beginning balances	(4)	47	32
Change in fair value of derivative instruments	(51)	(37)	18
Change in fair value of derivatives instruments, (income) expense reclassified into operations from other comprehensive income	19	(14)	(8)
Reclassification of stranded tax effects, change in fair value of derivative instruments			5
Change in fair value of derivative instruments, ending balances	(36)	(4)	47
Accumulated other comprehensive income (loss), net of tax, beginning balances	(460)	(381)	(278)
Unrealized gains (losses) on available-for-sale securities, net of income taxes	11	11	(5)
Foreign currency translation adjustments	12		(63)
Defined benefit plans	(55)	(49)	34
Change in fair value of derivative instruments, net of income tax benefit	(51)	(37)	18
Expense (income) reclassified into operations from other comprehensive income, Total	41	(4)	8
Reclassification of stranded tax effects, total			(95)
Accumulated other comprehensive income (loss), net of tax, ending balances	$ (502)	$ (460)	$ (381)

Other comprehensive income loss reclassification of stranded tax effects.

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Other comprehensive income loss reclassification of stranded tax effects change in fair value of derivative instruments.

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Other comprehensive income loss reclassification of stranded tax effects defined benefit plans.

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Other comprehensive income loss reclassification of stranded tax effects foreign currency translation adjustments.

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Other Comprehensive Income Loss Reclassification of Stranded Tax Effects Unrealized Gains Losses on Available for Sale Securities

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Amount, after tax, of accumulated unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

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Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount, after tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount, after tax, of reclassification adjustment from accumulated other comprehensive (income) loss for net periodic benefit cost (credit) of defined benefit plan.

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount, after tax and before adjustment, of unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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