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 gain before deducting unrealized loss on investments in equity securities classified as available-for-sale securities.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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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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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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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping.

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-Topic 320
-SubTopic 10
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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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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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This element represents the amount of any change recognized during the period in the high-end of the estimated range of outcomes (undiscounted) of a liability assumed in a business combination arising from an item of contingent consideration.

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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 7
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Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Oct. 01, 2017	Sep. 30, 2018	Oct. 01, 2017	Dec. 31, 2017
Financial Instruments and Fair Value [Line Items]
Available-for-sale securities, realized gain	$ 200,000	$ 200,000	$ 600,000	$ 700,000
Available-for-sale securities, realized loss			1,600,000	$ 300,000
Unrealized gains related to equity securities	1,000,000		1,400,000
Available-for-sale marketable securities, Fair Market Value of Investments in debt securities with Unrealized Losses	461,349,000		461,349,000		$ 1,350,896,000
Fair market value of investments with unrealized losses greater than one year	76,100,000		76,100,000		141,000,000
Aggregate loss of investments with unrealized losses greater than one year	2,100,000		2,100,000		1,200,000
Fair market value of investments with unrealized losses less than one year	385,300,000		385,300,000		1,209,900,000
Aggregate loss of investments with unrealized losses less than one year	1,300,000		1,300,000		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	1,786,000		1,786,000
Available for sale securities with out contractual maturity date	3,100,000		3,100,000
Universal Robots (UR)
Financial Instruments and Fair Value [Line Items]
Maximum payment per earn-out			25,000,000
Mobile Industrial Robots (MiR)
Financial Instruments and Fair Value [Line Items]
Maximum amount of contingent consideration paid for acquisition	118,900,000		118,900,000
Foreign Exchange Contracts
Financial Instruments and Fair Value [Line Items]
Notional amount of foreign currency forward contracts	$ 166,600,000		$ 166,600,000		$ 116,800,000