Consolidated Balance Sheets (Parentheticals) $ in Millions	Dec. 31, 2022 USD ($) shares	Dec. 31, 2021 USD ($) shares
Statement of Financial Position [Abstract]
Fixed maturities, available-for-sale, valuation allowance	$ 169	$ 14
Fixed maturities, available-for-sale, at amortized cost	93,355	90,493
Fixed maturities, held-to-maturity, valuation allowance	34	35
Fixed maturities, held-to-maturity, fair value	8,439	10,647
Short-term investments amortized cost	4,962	3,147
Premium Receivable, Allowance for Credit Loss	52	46
Valuation allowance for uncollectible reinsurance	$ 351	$ 329
Common Shares, shares issued | shares	446,376,614	474,021,114
Common Shares, shares outstanding | shares	414,594,856	426,572,612
Treasury Stock, Shares | shares	31,781,758	47,448,502