Investments (Distribution By Contractual Maturity Of Available-For-Sale and Held-To-Maturity Investments) (Detail) - Fixed Maturities [Member] $ in Millions	Jun. 30, 2021 USD ($)
Available For Sale Securities [Abstract]
Due in one year or less	$ 509
Due after one year through five years	311
Due after five years through ten years	307
Due after ten years	648
Mortgage-Backed and Asset-Backed	560
Total Available-For-Sale, amortized cost	2,335
Due in one year or less	509
Due after one year through five years	326
Due after five years through ten years	327
Due after ten years	738
Mortgage-Backed and Asset-Backed	573
Total Available-For-Sale, fair value	$ 2,473