Investments (Distribution By Contractual Maturity Of Available-For-Sale and Held-To-Maturity Investments) (Detail) - Fixed Maturities [Member] - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Available For Sale Securities [Abstract]
Due in one year or less	$ 519
Due after one year through five years	470
Due after five years through ten years	512
Due after ten years	1,000
Mortgage-Backed and Asset-Backed	624
Total Available-For-Sale, amortized cost	3,125
Due in one year or less	520
Due after one year through five years	466
Due after five years through ten years	495
Due after ten years	994
Mortgage-Backed and Asset-Backed	619
Total Available-For-Sale, fair value	$ 3,094	$ 2,457