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Cash Equivalents and Marketable Securities - Classification of Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2022 | Dec. 31, 2021
Classified as: |  |
Cash equivalents | $ 92,692 | $ 115,335
Marketable securities - current | 206,812 | 203,235
Total cash equivalents and marketable securities | $ 299,504 | $ 318,570
Contractual maturities |  |
Maximum period of current contractual maturities | 1 year | 1 year
Realized Gain (loss) | $ 0 | $ 0

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