Investments (Maturity Distribution) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale, Amortized Cost
Due in one year or less	$ 43,909
Available-for-sale Securities, Debt Maturities, Due After One Year Through Five Years, Amortized Cost Basis	110,505
Available-for-sale Securities, Debt Maturities, Due After Five Years Through Ten Years, Amortized Cost Basis	214,028
Available-for-sale Securities, Debt Maturities, Due After Ten Years, Amortized Cost Basis	992,812
Debt Securities, Available-for-sale, Amortized Cost	1,361,254	$ 1,343,755
Debt Securities, Available-for-sale, Fair Value
Due in one year or less	44,649
Available-for-sale Securities, Debt Maturities, Due After One Year Through Five Years, Fair Value	113,784
Available-for-sale Securities, Debt Maturities, Due After Five Years Through Ten Years, Fair Value	221,903
Available-for-sale Securities, Debt Maturities, Due After Ten Years, Fair Value	975,074
Fixed maturity securities, available-for-sale	$ 1,355,410	$ 1,470,617

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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