Fair Value Measurements - Schedule of Fair Value of Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	$ 88,847	$ 73,826
Short-term investments	88,847	73,826
Other assets	45,286	38,682
Other liabilities	3,924	1,317
Foreign Exchange Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - currency forward contracts	4,232	2,485
Derivatives - liabilities	308	1,168
Interest Rate Hedge [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - interest rate hedge - non-current	1,180	6,083
Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	196,545	290,097
Cash and cash equivalents, including restricted cash (1)	79,270	187,405
Short-term investments	88,847	73,826
Derivatives - currency forward contracts	4,232
Total current assets	172,349	263,716
Available-for-sale investments	5,746	5,890
Other assets	18,450	20,491
Total long-term assets	24,196	26,381
Derivatives - liabilities	308	1,168
Total liabilities	7,216
Other liabilities	6,908
Fair Value Measurements, Recurring [Member] \| Foreign Exchange Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - currency forward contracts	4,232	2,485
Fair Value Measurements, Recurring [Member] \| Interest Rate Hedge [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - interest rate hedge - non-current		6,083
Derivatives – currency forward contracts	6,908
Fair Value Measurements, Recurring [Member] \| Currency Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - currency forward contracts		2,485
Derivatives - liabilities	308	1,168
Money Market Funds [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	4,732	180,340
Restricted cash - money market funds	330	110
Deferred compensation plan assets	483
Time Deposits and Certificates of Deposit [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	4,651	850
Available-for-sale investments	6,262	102
U.S. Agency Obligations [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	20,592	3,418
Available-for-sale investments	29,462	21,613
Bankers' Acceptance Drafts [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	4,540	989
Asset-Backed Securities [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments		9,113
U.S. Treasury Obligations [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	7,999
Available-for-sale investments	3,602	13,298
Mutual Funds and Exchange Traded Funds [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation plan assets	1,832
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	5,062	180,450
Cash and cash equivalents, including restricted cash (1)	5,062	180,450
Total current assets	5,062	180,450
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member] \| Money Market Funds [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	4,732	180,340
Restricted cash - money market funds	330	110
Significant Other Observable Inputs (Level 2) [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	191,483	109,647
Cash and cash equivalents, including restricted cash (1)	74,208	6,955
Short-term investments	88,847	73,826
Derivatives - currency forward contracts	4,232
Total current assets	167,287	83,266
Available-for-sale investments	5,746	5,890
Other assets	18,450	20,491
Total long-term assets	24,196	26,381
Derivatives - liabilities	308	1,168
Total liabilities	7,216
Other liabilities	6,908
Significant Other Observable Inputs (Level 2) [Member] \| Fair Value Measurements, Recurring [Member] \| Foreign Exchange Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - currency forward contracts	4,232	2,485
Significant Other Observable Inputs (Level 2) [Member] \| Fair Value Measurements, Recurring [Member] \| Interest Rate Hedge [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - interest rate hedge - non-current		6,083
Derivatives – currency forward contracts	6,908
Significant Other Observable Inputs (Level 2) [Member] \| Fair Value Measurements, Recurring [Member] \| Currency Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - currency forward contracts		2,485
Derivatives - liabilities	308	1,168
Significant Other Observable Inputs (Level 2) [Member] \| Money Market Funds [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation plan assets	483
Significant Other Observable Inputs (Level 2) [Member] \| Time Deposits and Certificates of Deposit [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	4,651	850
Available-for-sale investments	6,262	102
Significant Other Observable Inputs (Level 2) [Member] \| U.S. Agency Obligations [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	20,592	3,418
Available-for-sale investments	29,462	21,613
Significant Other Observable Inputs (Level 2) [Member] \| Bankers' Acceptance Drafts [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	4,540	989
Significant Other Observable Inputs (Level 2) [Member] \| Asset-Backed Securities [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments		9,113
Significant Other Observable Inputs (Level 2) [Member] \| U.S. Treasury Obligations [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	7,999
Available-for-sale investments	3,602	13,298
Significant Other Observable Inputs (Level 2) [Member] \| Mutual Funds and Exchange Traded Funds [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation plan assets	1,832
Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	44,981	19,359
Commercial Paper [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	40,966	2,687
Available-for-sale investments	44,981	19,359
Commercial Paper [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	40,966	2,687
Available-for-sale investments	44,981	19,359
Corporate Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments		9,352
Corporate Obligations [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments		9,352
Corporate Obligations [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments		9,352
Group Insurance Contracts [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	5,746
Available-for-sale investments		5,890
Group Insurance Contracts [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	5,746
Available-for-sale investments		5,890
Israeli Pension Assets [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Pension assets	16,135	14,408
Israeli Pension Assets [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Pension assets	$ 16,135	$ 14,408

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Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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Fair value as of the balance sheet date of all foreign currency derivative assets designated as cash flow hedging instruments.

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Amount of noncurrent assets classified as other.

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