Summary of Investments - Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Available-For-Sale, Amortized Cost
Due in one year or less	$ 45,019
Due after one year through five years	443,505
Due after five years through 10 years	540,068
Due after 10 years	385,967
Amortized Cost	1,681,752	$ 1,656,797
Available-For-Sale, Fair Value
Due in one year or less	44,925
Due after one year through five years	427,654
Due after five years through 10 years	488,978
Due after 10 years	349,777
Fair Value	1,547,061	1,719,790
Asset-backed securities
Available-For-Sale, Amortized Cost
Securities not categorized by contractual maturity	3,942
Amortized Cost	3,942	325
Available-For-Sale, Fair Value
Securities not categorized by contractual maturity	4,215
Fair Value	4,215	925
Mortgage-backed securities
Available-For-Sale, Amortized Cost
Securities not categorized by contractual maturity	21,063
Amortized Cost	21,063	25,075
Available-For-Sale, Fair Value
Securities not categorized by contractual maturity	18,053
Fair Value	18,053	25,013
Collateralized mortgage obligations
Available-For-Sale, Amortized Cost
Securities not categorized by contractual maturity	242,188
Available-For-Sale, Fair Value
Securities not categorized by contractual maturity	213,550
Fixed maturities
Available-For-Sale, Amortized Cost
Amortized Cost	1,681,752	$ 1,656,797
Available-For-Sale, Fair Value
Fair Value	$ 1,547,152

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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