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Investments - Summary of Investments Accounted for Available-for-Sale-Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Schedule Of Available For Sale Securities [Line Items] |  |
Available for sale securities, Amortized cost | $ 98,920 | $ 53,323
Available for sale securities, Unrealized losses | (162) | (1)
Available for sale securities, Unrealized gains |  | 3
Available for sale securities, Estimated fair value | 98,758 | 53,325
Short-Term Investments | US Treasury Securities |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Available for sale securities, Amortized cost | 18,116 | 38,489
Available for sale securities, Unrealized losses | (19) |
Available for sale securities, Unrealized gains |  | 3
Available for sale securities, Estimated fair value | $ 18,097 | $ 38,492
Short-Term Investments | US Treasury Securities | Maximum |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Maturity | 1 year | 1 year
Short-Term Investments | Corporate Debt Securities |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Available for sale securities, Amortized cost | $ 2,824 | $ 3,794
Available for sale securities, Unrealized losses | (2) | (1)
Available for sale securities, Estimated fair value | $ 2,822 | $ 3,793
Short-Term Investments | Corporate Debt Securities | Maximum |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Maturity | 1 year | 1 year
Short-Term Investments | Commercial Paper |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Available for sale securities, Amortized cost | $ 31,566 | $ 11,040
Available for sale securities, Estimated fair value | $ 31,566 | $ 11,040
Short-Term Investments | Commercial Paper | Maximum |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Maturity | 1 year | 1 year
Short-Term Investments | Supranational Debt Securities |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Available for sale securities, Amortized cost | $ 1,503 |
Available for sale securities, Estimated fair value | $ 1,503 |
Short-Term Investments | Supranational Debt Securities | Maximum |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Maturity | 1 year |
Long-Term Investments | US Treasury Securities |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Available for sale securities, Amortized cost | $ 44,911 |
Available for sale securities, Unrealized losses | (141) |
Available for sale securities, Estimated fair value | $ 44,770 |
Long-Term Investments | US Treasury Securities | Minimum |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Maturity | 1 year |
Long-Term Investments | US Treasury Securities | Maximum |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Maturity | 2 years |

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- Definition 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). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563 + Details
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