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Financial Instruments - Additional Information (Detail) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jul. 01, 2018 | Jul. 02, 2017 | Jul. 01, 2018 | Jul. 02, 2017 | Dec. 31, 2017
Financial Instruments and Fair Value [Line Items] |  |  |  |  |
Available-for-sale securities, realized gain | $ 100,000 | $ 200,000 | $ 400,000 | $ 500,000 |
Available-for-sale securities, realized loss | 0 | $ 100,000 | 1,500,000 | $ 200,000 |
Available-for-sale marketable securities, Fair Market Value of Investments in debt securities with Unrealized Losses | 691,584,000 |  | 691,584,000 |  | $ 1,350,895,000
Fair market value of investments with unrealized losses greater than one year | 32,700,000 |  | 32,700,000 |  | 141,000,000
Aggregate loss of investments with unrealized losses greater than one year | 1,600,000 |  | 1,600,000 |  | 1,200,000
Fair market value of investments with unrealized losses less than one year | 658,900,000 |  | 658,900,000 |  | 1,209,900,000
Aggregate loss of investments with unrealized losses less than one year | 1,700,000 |  | 1,700,000 |  | 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 | 1,681,000 |  | 1,681,000 |  |
Available for sale securities with out contractual maturity date | 2,800,000 |  | 2,800,000 |  |
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 | 117,000,000 |  | 117,000,000 |  |
Foreign Exchange Contracts |  |  |  |  |
Financial Instruments and Fair Value [Line Items] |  |  |  |  |
Notional amount of foreign currency forward contracts | $ 93,400,000 |  | $ 93,400,000 |  | $ 116,800,000

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References 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 + Details
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- Definition Financial Instruments and Fair Value [Line Items] + References No definition available. + Details
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- Definition 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. + References No definition available. + Details
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- Definition 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. + References No definition available. + Details
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- Definition 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 twelve months or longer. + References No definition available. + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27198-111563 + Details
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- Definition This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. + References No definition available. + Details
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- Definition This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. + References No definition available. + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7008-128479 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 + Details
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- Definition 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 less than 12 months. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 + Details
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