Summary of Investments - Maturities (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Available-For-Sale, Amortized Cost
Due in one year or less	$ 52,679
Due after one year through five years	446,499
Due after five years through 10 years	505,017
Due after 10 years	397,249
Available-For-Sale, Fair Value
Due in one year or less	52,763
Due after one year through five years	442,023
Due after five years through 10 years	478,279
Due after 10 years	377,213
Fair Value	1,597,284	$ 1,719,790
Asset-backed securities
Available-For-Sale, Amortized Cost
Securities not categorized by contractual maturity	3,952
Amortized Cost	3,952	325
Available-For-Sale, Fair Value
Securities not categorized by contractual maturity	4,371
Fair Value	4,371	925
Mortgage-backed securities
Available-For-Sale, Amortized Cost
Securities not categorized by contractual maturity	21,910
Amortized Cost	21,910	25,075
Available-For-Sale, Fair Value
Securities not categorized by contractual maturity	19,959
Fair Value	19,959	$ 25,013
Collateralized mortgage obligations
Available-For-Sale, Amortized Cost
Securities not categorized by contractual maturity	240,242
Available-For-Sale, Fair Value
Securities not categorized by contractual maturity	222,676
Fixed maturities
Available-For-Sale, Amortized Cost
Amortized Cost	1,667,548
Available-For-Sale, Fair Value
Fair Value	$ 1,597,284

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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