Short-term investments - Contractual Maturities Of Short-Term Investments Designated As Available-For-Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost, Due in less than 1 year	$ 88,194
Fair Value, Due in less than 1 year	88,438
Adjusted Cost, Due in 1 to 5 years	4,416
Fair Value, Due in 1 to 5 years	4,415
Adjusted Cost	92,610	$ 237,423
Fair Value	92,853	237,983
Carrying value of equity method investments	20,000
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost, Due in less than 1 year	88,194
Fair Value, Due in less than 1 year	88,438
Adjusted Cost, Due in 1 to 5 years	4,416
Fair Value, Due in 1 to 5 years	4,415
Fair Value	$ 92,853	$ 237,983

Amortized cost of 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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-Publisher FASB
-Name Accounting Standards Codification
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Amount of 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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