Marketable Securities - Schedule of Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Fair Value	$ 149,680	$ 54,384
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Less than 1 Year	6,054
1-5 Years	14,468
5-10 Years	1,633
Greater than 10 Years	0
Fair Value	22,155	4,098
Government securities - U.S.
Debt Securities, Available-for-sale [Line Items]
Less than 1 Year	0
1-5 Years	13,827
5-10 Years	2,038
Greater than 10 Years	3,134
Fair Value	18,999	5,446
Other fixed-income securities
Debt Securities, Available-for-sale [Line Items]
Less than 1 Year	1,017
1-5 Years	2,837
5-10 Years	0
Greater than 10 Years	0
Fair Value	3,854	$ 1,637
Debt Securities
Debt Securities, Available-for-sale [Line Items]
Less than 1 Year	7,071
1-5 Years	31,132
5-10 Years	3,671
Greater than 10 Years	3,134
Fair Value	$ 45,008

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