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Financial Instruments - Additional Information (Detail) - USD ($) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Oct. 01, 2017 | Oct. 02, 2016 | Oct. 01, 2017 | Oct. 02, 2016 | Dec. 31, 2016
Financial Instruments and Fair Value [Line Items] |  |  |  |  |
Available-for-sale securities, realized loss | $ 0 | $ 100,000 | $ 300,000 | $ 400,000 |
Available-for-sale securities, realized gain | 200,000 | $ 700,000 | 700,000 | $ 1,200,000 |
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses | 1,243,640,000 |  | 1,243,640,000 |  | $ 732,979,000
Fair market value of investments with unrealized losses greater than one year | 113,300,000 |  | 113,300,000 |  | 2,900,000
Aggregate loss of investments with unrealized losses greater than one year |  |  | 900,000 |  | 300,000
Fair market value of investments with unrealized losses less than one year | 1,130,300,000 |  | 1,130,300,000 |  | 730,100,000
Aggregate loss of investments with unrealized losses less than one year |  |  | 1,400,000 |  | 2,500,000
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 | $ 79,200,000 |  | $ 79,200,000 |  | $ 83,900,000

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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 Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + 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 Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
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