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Cash Equivalents and Marketable Securities - Additional Information (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Marketable Securities [Line Items]
Fair value of securities in unrealized loss position	$ 312.5	$ 132.6
Securities, continuous unrealized loss position, less than twelve months, fair value	$ 312.5	$ 132.6
Maximum [Member]
Marketable Securities [Line Items]
Marketable securities maturity period	2 years	2 years

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- Definition

Marketable securities maturity period.

+ References

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X

- 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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X

- 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.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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