SCHEDULE I - SUMMARY OF INVESTMENTS OTHER THAN INVESTMENTS IN RELATED PARTIES (Details) $ in Millions	Dec. 31, 2019 USD ($)
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	$ 31,753
Amount shown in the Balance Sheet	33,607
United States government, government agencies and authorities
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	848
Fair value	882
Amount shown in the Balance Sheet	882
States, municipalities and political subdivisions
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	1,483
Fair value	1,755
Amount shown in the Balance Sheet	1,755
Foreign government
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	142
Fair value	149
Amount shown in the Balance Sheet	149
Public utilities
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	3,072
Fair value	3,390
Amount shown in the Balance Sheet	3,390
All other corporate bonds
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	14,229
Fair value	15,051
Amount shown in the Balance Sheet	15,051
Asset-backed securities
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	316
Fair value	317
Amount shown in the Balance Sheet	317
MBS
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	127
Fair value	181
Amount shown in the Balance Sheet	181
Fixed income securities
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	20,217
Fair value	21,725
Amount shown in the Balance Sheet	21,725
Public utilities
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	20
Fair value	30
Amount shown in the Balance Sheet	30
Banks, trusts and insurance companies
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	111
Fair value	158
Amount shown in the Balance Sheet	158
Industrial, miscellaneous and all other
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	967
Fair value	1,252
Amount shown in the Balance Sheet	1,252
Nonredeemable preferred stocks
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	25
Fair value	29
Amount shown in the Balance Sheet	29
Equity securities
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	1,123
Fair value	1,469
Amount shown in the Balance Sheet	1,469
Mortgage loans on real estate
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	3,988
Fair value	4,176
Amount shown in the Balance Sheet	3,988
Real Estate Acquired in Satisfaction of Debt
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	0
Amount shown in the Balance Sheet	0
Real estate investment
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	292
Amount shown in the Balance Sheet	292
Policy loans
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	557
Amount shown in the Balance Sheet	557
Derivative instruments
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	124
Fair value	124
Amount shown in the Balance Sheet	124
Limited partnership interests
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	3,250
Amount shown in the Balance Sheet	3,250
Other long-term investments
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	1,011
Amount shown in the Balance Sheet	1,011
Short-term investments
Summary of Investments Other Than Investments in Related Parties
Cost/ amortized cost	1,191
Fair value	1,191
Amount shown in the Balance Sheet	$ 1,191