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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

X

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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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