Fair value Measurement - Additional Information (Details) - Fair Value, Recurring - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2022	Dec. 31, 2021
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Treasury bills	$ 174.4
Fair Value, Inputs, Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt Instrument, Fair Value Amount	$ 33.2	$ 32.7

Interest income on US treasury securities. US treasury securities are negotiable debt obligations of the US government, secured by its full faith and credit and issued at various schedules and maturities. The income from treasury securities is exempt from state and local, but not federal, taxes. There are three types of securities issued by the US treasury (bonds, bills, and notes), which are distinguished by the amount of time from the initial sale of the bond to maturity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.2)
-URI https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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Balance Type:	credit
Period Type:	duration