Investments (Distribution By Contractual Maturity Of Available-For-Sale and Held-To-Maturity Investments) (Detail) - Fixed Maturities [Member] - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Available For Sale Securities [Abstract]
Due in one year or less	$ 172
Due after one year through five years	379
Due after five years through ten years	280
Due after ten years	671
Mortgage-backed and asset-backed	412
Total fixed-maturity investments	1,914
Due in one year or less	172
Due after one year through five years	364
Due after five years through ten years	233
Due after ten years	518
Mortgage-backed and asset-backed	374
Total fixed-maturity investments	$ 1,661	$ 1,931