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Fair Value of Financial Assets and Liabilities - Additional Information (Detail) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020
Business Combinations contingent liabilities undiscounted maximum payment | $ 85,500,000 |
Business Combinations contingent liabilities undiscounted maximum payment term | 5 years |
Fair value transfers Into levels of financial instruments | $ 0 |
Fair Value, Inputs, Level 3 [Member] |  |
Business combination contingent consideration fair value disclosure | 28,000,000 | $ 39,800,000
Cash And Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Cash and cash equivalents fair value disclosure | $ 329,600,000 | $ 440,100,000

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- Definition 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. + References No definition available. + Details
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