Investments - Schedule of Fixed Maturities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Amortized Cost, net
Due in one year or less	$ 164,857
Due after one year through five years	1,068,265
Due after five years through ten years	1,670,440
Due after ten years through twenty years	7,785,675
Due after twenty years	7,486,945
Mortgage-backed and asset-backed securities	125,510
Fixed maturities, net of allowance for credit losses	18,301,692
Fair Value
Due in one year or less	165,085
Due after one year through five years	1,067,454
Due after five years through ten years	1,664,710
Due after ten years through twenty years	7,349,267
Due after twenty years	6,127,343
Mortgage-backed and asset-backed securities	129,506
Fixed maturities, fair value	$ 16,503,365	$ 21,305,287