Summary of Significant Accounting Policies - Schedule of Cash Equivalents and Short-Term Investments (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Short-Term Investments
Unrealized Gains	$ 0.0	$ 0.0
Unrealized Losses	0.0	(0.8)
Amortized Cost	298.4	467.0
Fair Value	298.4	466.2
U.S. Treasury securities
Short-Term Investments
Amortized Cost		317.4
Unrealized Gains		0.0
Unrealized Losses		(0.8)
Fair Value		316.6
Corporate debt securities
Short-Term Investments
Amortized Cost		20.1
Unrealized Gains		0.0
Unrealized Losses		0.0
Fair Value		20.1
Commercial paper
Short-Term Investments
Amortized Cost		125.1
Unrealized Gains		0.0
Unrealized Losses		0.0
Fair Value		125.1
Money market funds
Cash Equivalents
Cash equivalents, fair value	$ 298.4	$ 4.4

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Cash, Cash Equivalents And Available-for-sale Debt Securities, Amortized Cost

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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