Consolidated Balance Sheets (Parentheticals) (Unaudited) $ in Millions	Jun. 30, 2023 USD ($) shares	Dec. 31, 2022 USD ($) shares
Statement of Financial Position [Abstract]
Fixed maturities, available-for-sale, valuation allowance	$ 193	$ 169
Fixed maturities, available-for-sale, at amortized cost	104,224	93,355
Fixed maturities, held-to-maturity, valuation allowance	0	34
Fixed maturities, held-to-maturity, fair value	0	8,439
Short-term investments amortized cost	4,099	4,962
Premium Receivable, Allowance for Credit Loss	52	52
Valuation allowance for uncollectible reinsurance	$ 361	$ 351
Common Shares, shares issued | shares	431,451,586	446,376,614
Common Shares, shares outstanding | shares	410,691,354	414,594,856
Treasury Stock, Common, Shares | shares	20,760,232	31,781,758