General - Investments - Amortized Cost (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Amortized cost
Amortized Cost	$ 98,286	$ 101,599
Gross Unrealized Gains	59	78
Gross Unrealized Losses	(36)	(16)
Estimated Fair Value	98,309	101,661
U.S. Government and agency securities
Amortized cost
Amortized Cost	35,364	30,742
Gross Unrealized Gains	39	38
Gross Unrealized Losses	(1)	(5)
Estimated Fair Value	35,402	30,775
Corporate debt securities
Amortized cost
Amortized Cost	61,611	69,552
Gross Unrealized Gains	20	40
Gross Unrealized Losses	(35)	(11)
Estimated Fair Value	61,596	69,581
Certificates of deposit
Amortized cost
Amortized Cost	1,311	1,305
Estimated Fair Value	$ 1,311	$ 1,305

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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Amount, before tax, of unrealized loss 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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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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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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