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Financial Instruments - Additional Information (Detail) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 | Apr. 01, 2018 | Dec. 31, 2018
Financial Instruments and Fair Value [Line Items] |  |  |
Available-for-sale securities, realized gain | $ 100,000 | $ 300,000 |
Available-for-sale securities, realized loss | 100,000 | 1,500,000 |
Unrealized loss related to equity securities | 2,800,000 |  |
Available-for-sale marketable securities, Fair Market Value of Investments in debt securities with Unrealized Losses | 120,039,000 |  | $ 191,978,000
Fair market value of investments with unrealized losses greater than one year | 32,900,000 |  | 28,500,000
Aggregate loss of investments with unrealized losses greater than one year | 1,300,000 |  | 1,600,000
Fair market value of investments with unrealized losses less than one year | 87,100,000 |  | 163,500,000
Aggregate loss of investments with unrealized losses less than one year | 100,000 |  | 1,400,000
Unrealized Gain (loss) on contracts | 3,200,000 | $ 600,000 |
Debt Mutual Funds |  |  |
Financial Instruments and Fair Value [Line Items] |  |  |
Available for sale securities with out contractual maturity date | 3,300,000 |  |
Mobile Industrial Robots (MiR) |  |  |
Financial Instruments and Fair Value [Line Items] |  |  |
Maximum amount of contingent consideration paid for acquisition | 83,200,000 |  |
Foreign Exchange Contracts |  |  |
Financial Instruments and Fair Value [Line Items] |  |  |
Unrealized Gain (loss) on contracts | $ 148,800,000 |  | $ 163,100,000

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- Definition Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + 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 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 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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