Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2022	Dec. 31, 2021
Fixed maturities - available for sale, at market value, amortized cost	$ 23,204	$ 22,064
Fixed maturities - available for sale, at market value, allowance for credit loss	(38)	(30)
Fixed maturities - held to maturity, at amortized cost, net of credit allowances, fair value	817
Fixed maturities - held to maturity, at amortized cost, credit allowances	(9)
Short-term investments, at cost	$ 611	$ 1,178
Preferred shares, par value	$ 0.01	$ 0.01
Preferred shares, authorized	50,000,000.0	50,000,000
Preferred shares, issued	0	0
Preferred shares, outstanding	0	0
Common shares, par value	$ 0.01	$ 0.01
Common Stock, Shares Authorized	200,000,000.0	200,000,000
Common shares, outstanding	69,900,000	69,800,000
Accumulated other comprehensive income (loss), net deferred income tax expense (benefit)	$ (269)	$ 27
Treasury shares	30,800,000	30,500,000