Unaudited Consolidated Balance Sheets (Parenthetical) - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Amortized Cost	$ 8,456,620,000	$ 8,587,179,000
Fair Value	$ 392,123,000	$ 0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock issued (in shares)	183,438,711	186,305,332
Common stock outstanding (in shares)	183,438,711	186,305,332

Face amount or stated value per share of common stock.

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