Investments - Contractual Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Amortized Cost
Less: loaned securities	$ 203,693	$ 112,139
Total fixed-maturities, available for sale, Amortized Cost	5,599,111	5,587,261
Fair Value
Less: loaned securities	203,693	112,139
Total fixed-maturities available for sale, Fair Value	5,188,228	5,017,711
Non asset-backed securities
Amortized Cost
Due in one year or less	120,944
Due after one year through five years	1,296,391
Due after five years through 10 years	928,170
Due after 10 years	865,531
Fair Value
Due in one year or less	119,450
Due after one year through five years	1,243,001
Due after five years through 10 years	850,861
Due after 10 years	708,240
Asset-backed securities and mortgage-related assets
Amortized Cost
Asset-backed and mortgage-backed securities	2,523,731
Fair Value
Asset-backed and mortgage-backed securities	2,393,858
Total fixed-maturities available for sale
Amortized Cost
Total	5,734,767	5,643,459
Total fixed-maturities, available for sale, Amortized Cost	5,599,111	5,587,261
Fair Value
Total	5,315,410	5,064,900
Total fixed-maturities available for sale, Fair Value	5,188,228	5,017,711
Total fixed-maturities available for sale \| Total fixed-maturities available for sale
Amortized Cost
Total	5,734,767
Total fixed-maturities, available for sale, Amortized Cost	5,599,111
Fair Value
Total	5,315,410
Total fixed-maturities available for sale, Fair Value	5,188,228
Loaned securities, amortized cost \| Total fixed-maturities available for sale
Amortized Cost
Less: loaned securities	135,656	56,198
Fair Value
Less: loaned securities	135,656	56,198
Loaned securities
Amortized Cost
Less: loaned securities	127,000
Fair Value
Less: loaned securities	127,000
Loaned securities \| Total fixed-maturities available for sale
Amortized Cost
Less: loaned securities	127,182	47,189
Fair Value
Less: loaned securities	$ 127,182	$ 47,189

Available-For-Sale Debt Securities, Amortized Cost Basis, Including Loaned Securities

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