Fair Value Measurements - Schedule of Fair Value of Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	$ 44,326	$ 73,826
Short-term investments	44,326	73,826
Derivatives - currency forward contracts		2,485
Other assets	48,562	38,682
Derivatives - liabilities		1,168
Foreign Exchange Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - currency forward contracts	3,492
Derivatives - liabilities	322
Interest Rate Hedge [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - interest rate hedge - non-current	4,459	6,083
Derivatives - currency forward contracts	4,459	6,083
Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	223,482	290,097
Cash and cash equivalents, including restricted cash (1)	148,701	187,405
Short-term investments	44,326	73,826
Derivatives - currency forward contracts	3,492	2,485
Total current assets	196,519	263,716
Available-for-sale investments	5,950	5,890
Other assets	21,013	20,491
Total long-term assets	26,963	26,381
Derivatives - liabilities	322	1,168
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	3,492
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	4,459	6,083
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	322	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	294	180,340
Restricted cash - money market funds	317	110
Deferred compensation plan assets	274
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	3,852	850
Available-for-sale investments	101	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	49,084	3,418
Available-for-sale investments		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	1,722	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]
Available-for-sale investments		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	1,799
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	611	180,450
Cash and cash equivalents, including restricted cash (1)	611	180,450
Total current assets	611	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	294	180,340
Restricted cash - money market funds	317	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	222,871	109,647
Cash and cash equivalents, including restricted cash (1)	148,090	6,955
Short-term investments	44,326	73,826
Derivatives - currency forward contracts	3,492	2,485
Total current assets	195,908	83,266
Available-for-sale investments	5,950	5,890
Other assets	21,013	20,491
Total long-term assets	26,963	26,381
Derivatives - liabilities	322	1,168
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	3,492
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	4,459	6,083
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	322	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	274
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	3,852	850
Available-for-sale investments	101	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	49,084	3,418
Available-for-sale investments		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	1,722	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]
Available-for-sale investments		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	1,799
Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	33,509	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	82,584	2,687
Available-for-sale investments	33,509	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	82,584	2,687
Available-for-sale investments	33,509	19,359
Corporate Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	8,994	9,352
Corporate Obligations [Member] \| Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	12,570
Available-for-sale investments	8,994	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]
Cash and cash equivalents	12,570
Available-for-sale investments	8,994	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	5,950
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	5,950
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	14,481	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	$ 14,481	$ 14,408

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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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