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Investments (Distribution By Contractual Maturity Of Available-For-Sale and Held-To-Maturity Investments) (Detail) - Fixed Maturities [Member] $ in Millions | Sep. 30, 2020 USD ($)
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Available For Sale Securities [Abstract] |
Due in one year or less | $ 560
Due after one year through five years | 473
Due after five years through ten years | 269
Due after ten years | 657
Mortgage-Backed and Asset-Backed | 552
Total Available-For-Sale, amortized cost | 2,511
Due in one year or less | 562
Due after one year through five years | 490
Due after five years through ten years | 297
Due after ten years | 791
Mortgage-Backed and Asset-Backed | 561
Total Available-For-Sale, fair value | 2,701
Variable Interest Entity Primary Beneficiary [Member] |
Held To Maturity Securities [Abstract] |
Due in one year or less | 0
Due after one year through five years | 0
Due after five years through ten years | 0
Due after ten years | 575
Mortgage-Backed and Asset-Backed | 0
Total held-to-maturity, amortized cost | 575
Due in one year or less | 0
Due after one year through five years | 0
Due after five years through ten years | 0
Due after ten years | 575
Mortgage-Backed and Asset-Backed | 0
Held-To-Maturity Securities Fair Value | $ 575

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