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Financial Instruments - Additional Information (Detail) - USD ($) $ in Millions | Sep. 30, 2021 | Dec. 31, 2020
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Strategic Investment | Fair Value, Measurements, Recurring |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Strategic investments fair value | $ 16.3 | $ 10.5

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- Definition Amount of investment in equity security without readily determinable fair value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123583765&loc=SL75117539-209714 + Details
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