General - Investments by Maturity Date (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Amortized Cost
2020	$ 31,033
2021	65,705
2022	1,548
Amortized Cost	98,286	$ 101,599
Estimated Fair Value
2020	31,053
2021	65,708
2022	1,548
Estimated Fair Value	$ 98,309	$ 101,661

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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