Investments - Schedule of Investments' Gross Unrealized Loss and Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Fair Value, Less than 12 Months	$ 2,803
Unrealized Losses, Less than 12 Months	(11)
Fair Value, 12 Months or More		$ 8,051
Unrealized Losses, 12 Months or More		(47)
Fair Value	2,803	8,051
Unrealized Losses	(11)	(47)
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	1,995
Unrealized Losses, Less than 12 Months	(5)
Fair Value, 12 Months or More		7,053
Unrealized Losses, 12 Months or More		(39)
Fair Value	1,995	7,053
Unrealized Losses	(5)	(39)
Corporate debt
Debt Securities, Available-for-sale [Line Items]
Fair Value, Less than 12 Months	808
Unrealized Losses, Less than 12 Months	(6)
Fair Value, 12 Months or More		998
Unrealized Losses, 12 Months or More		(8)
Fair Value	808	998
Unrealized Losses	$ (6)	$ (8)

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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