Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
Apr. 01, 2018	Apr. 02, 2017	Dec. 31, 2017
Financial Instruments and Fair Value [Line Items]
Available-for-sale securities, realized loss	$ 1,500,000	$ 200,000
Available-for-sale securities, realized gain	300,000	$ 300,000
Available-for-sale marketable securities, Fair Market Value of Investments in debt securities with Unrealized Losses	890,956,000		$ 1,350,896,000
Fair market value of investments with unrealized losses greater than one year	62,100,000		141,000,000
Aggregate loss of investments with unrealized losses greater than one year	1,600,000		1,200,000
Fair market value of investments with unrealized losses less than one year	828,900,000		1,209,900,000
Aggregate loss of investments with unrealized losses less than one year	1,900,000		2,200,000
Debt Mutual Funds
Financial Instruments and Fair Value [Line Items]
Available-for-sale marketable securities, Fair Market Value of Investments in debt securities with Unrealized Losses	1,679,000
Available for sale securities with out contractual maturity date	2,700,000
Universal Robots
Financial Instruments and Fair Value [Line Items]
Maximum payment per earn-out	25,000,000
Foreign Exchange Contracts
Financial Instruments and Fair Value [Line Items]
Notional amount of foreign currency forward contracts	$ 108,800,000		$ 116,800,000

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Financial Instruments and Fair Value [Line Items]

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Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer.

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This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

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Amount of unrealized loss on investments in available-for-sale securities that have been in a loss position for less than twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount of available-for-sale debt securities at fair value that do not have a single maturity date and which the entity has decided to disclose separately rather than allocating the fair value over several maturity groupings.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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