Investments - Schedule of Investments' Gross Unrealized Loss and Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Fair Value, Less than 12 Months	$ 14,773	$ 2,803
Unrealized Losses, Less than 12 Months	(201)	(11)
Fair Value, 12 Months or More	0	0
Unrealized Losses, 12 Months or More	0	0
Fair Value	14,773	2,803
Unrealized Losses	(201)	(11)
U.S. Treasury securities, obligations of U.S. Government agencies and municipalities
Debt Securities, Available-for-sale [Line Items]
Fair Value, Less than 12 Months	11,864	1,995
Unrealized Losses, Less than 12 Months	(184)	(5)
Fair Value, 12 Months or More	0	0
Unrealized Losses, 12 Months or More	0	0
Fair Value	11,864	1,995
Unrealized Losses	(184)	(5)
Corporate debt
Debt Securities, Available-for-sale [Line Items]
Fair Value, Less than 12 Months	2,909	808
Unrealized Losses, Less than 12 Months	(17)	(6)
Fair Value, 12 Months or More	0	0
Unrealized Losses, 12 Months or More	0	0
Fair Value	2,909	808
Unrealized Losses	$ (17)	$ (6)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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