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Financial Instruments - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Oct. 03, 2021 | Sep. 27, 2020 | Oct. 03, 2021 | Sep. 27, 2020 | Dec. 31, 2020
Financial Instruments and Fair Value [Line Items] |  |  |  |  |
Available-for-sale securities, realized gain | $ 0.5 | $ 1.1 | $ 2.6 | $ 4.1 |
Available-for-sale securities, realized loss | 0.0 | 0.1 | 0.0 | 0.3 |
Aggregate loss of investments with unrealized losses greater than one year | 6.2 |  | 6.2 |  |
Fair market value of investments with unrealized losses less than one year | 57.3 |  | 57.3 |  | $ 70.4
Unrealized Gain (loss) on contracts | 1.0 | 1.2 | 1.3 | 0.4 |
Equity securities unrealized gain |  | $ 2.0 | 3.3 | 5.7 |
Equity securities unrealized loss | 0.4 |  | 1.1 | $ 6.0 |
Debt Mutual Funds |  |  |  |  |
Financial Instruments and Fair Value [Line Items] |  |  |  |  |
Available for sale securities with out contractual maturity date | $ 8.9 |  | 8.9 |  |
Foreign Exchange Contracts |  |  |  |  |
Financial Instruments and Fair Value [Line Items] |  |  |  |  |
Unrealized Gain (loss) on contracts |  |  | $ 181.8 |  | $ 152.9

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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 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=123581744&loc=d3e27198-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 3A -URI http://asc.fasb.org/extlink&oid=123599081&loc=SL120269850-112803 + 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 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, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + 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=123581744&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922890-210455 + Details
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- Definition Amount before tax of foreign currency transaction unrealized gain (loss) recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124440516&loc=d3e30840-110895 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=125521441&loc=d3e30690-110894 + Details
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