Investments (Distribution By Contractual Maturity Of Available-For-Sale and Held-To-Maturity Investments) (Detail) - Fixed Maturities [Member] $ in Millions	Dec. 31, 2021 USD ($)
Available For Sale Securities [Abstract]
Due in one year or less	$ 412
Due after one year through five years	328
Due after five years through ten years	364
Due after ten years	736
Mortgage-Backed and Asset-Backed	476
Total Available-For-Sale, amortized cost	2,316
Due in one year or less	413
Due after one year through five years	339
Due after five years through ten years	380
Due after ten years	836
Mortgage-Backed and Asset-Backed	489
Total Available-For-Sale, fair value	$ 2,457