Financial Instruments - Additional Information (Detail) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($) Customer	Dec. 31, 2017 USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
Long-term debt due within one year	$ 201	$ 108
Debt instrument maturity period	1 year
Book value of senior notes	$ 3,030
Sales Revenue, Net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Number of largest customers \| Customer	6
Sales Revenue, Net [Member] \| Customer Concentration Risk [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Percentage of sales to six largest customers	77.00%	81.00%
Fair Value, Inputs, Level 1 [Member] \| Senior Notes [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Estimated fair value of notes payable	$ 3,050
Foreign Exchange Forward [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Foreign exchange forward contracts, gain recognized in other comprehensive loss	34
Foreign exchange forward contracts, loss recognized in other comprehensive loss	$ 101

Maturity period of term loan facility under sub tranche.

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Derivative instrument gain recognized in other comprehensive income effective portion.

+ References

No definition available.

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- Definition

Derivative instrument loss recognized in other comprehensive income effective portion.

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Number of largest customers.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Fair value portion of notes payable.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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