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Financial Instruments - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Financial Instruments and Fair Value [Line Items] |  |  |
Available-for-sale securities, realized gain | $ 3.1 | $ 4.6 | $ 1.3
Available-for-sale securities, realized loss | 0.0 | 0.3 | 0.2
Aggregate loss of investments with unrealized losses greater than one year | 6.5 |  |
Aggregate loss of investments with unrealized losses less than one year | 85.4 | 70.4 |
Unrealized Gain (loss) on contracts | 2.1 | 2.6 | $ 1.6
Equity securities unrealized gain | 5.1 | 9.6 |
Equity securities unrealized loss | $ 1.8 | $ 6.0 |
Accounts Receivable | Customer 1 | Minimum |  |  |
Financial Instruments and Fair Value [Line Items] |  |  |
Concentration risk, percentage |  | 25.00% |
Accounts Receivable | Customer 2 | Minimum |  |  |
Financial Instruments and Fair Value [Line Items] |  |  |
Concentration risk, percentage | 10.00% |  |
Debt Mutual Funds |  |  |
Financial Instruments and Fair Value [Line Items] |  |  |
Available for sale securities with out contractual maturity date | $ 8.0 |  |
Foreign Exchange Contracts |  |  |
Financial Instruments and Fair Value [Line Items] |  |  |
Unrealized Gain (loss) on contracts | $ 0.1 | $ 0.4 |

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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 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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