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

Available for sale securities gross realized gain.

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Available for sale securities gross realized loss.

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Concentration risk, percentages.

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Financial Instruments and Fair Value [Line Items]

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Foreign Currency Transaction Gain, Unrealized

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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.

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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.

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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 less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount before tax of foreign currency transaction unrealized gain (loss) recognized in the income statement.

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