SCHEDULE I - SUMMARY OF INVESTMENTS OTHER THAN INVESTMENTS IN RELATED PARTIES (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	$ 77,930
Amount at which shown in the Balance Sheet	81,113
United States government, government agencies and authorities
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	4,192
Fair value	4,328
Amount at which shown in the Balance Sheet	4,328
States, municipalities and political subdivisions
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	7,877
Fair value	8,497
Amount at which shown in the Balance Sheet	8,497
Foreign governments
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	1,543
Fair value	1,645
Amount at which shown in the Balance Sheet	1,645
Public utilities
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	4,985
Fair value	5,519
Amount at which shown in the Balance Sheet	5,519
Convertibles and bonds with warrants attached
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	209
Fair value	186
Amount at which shown in the Balance Sheet	186
All other corporate bonds
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	35,192
Fair value	36,439
Amount at which shown in the Balance Sheet	36,439
Asset-backed securities
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	3,971
Fair value	3,978
Amount at which shown in the Balance Sheet	3,978
Residential mortgage-backed securities
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	1,108
Fair value	1,207
Amount at which shown in the Balance Sheet	1,207
Commercial mortgage-backed securities
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	573
Fair value	615
Amount at which shown in the Balance Sheet	615
Redeemable preferred stock
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	22
Fair value	26
Amount at which shown in the Balance Sheet	26
Fixed income securities
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	59,672
Fair value	62,440
Amount at which shown in the Balance Sheet	62,440
Public utilities
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	94
Fair value	107
Amount at which shown in the Balance Sheet	107
Banks, trust and insurance companies
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	792
Fair value	866
Amount at which shown in the Balance Sheet	866
Industrial, miscellaneous and all other
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	2,712
Fair value	3,013
Amount at which shown in the Balance Sheet	3,013
Non-redeemable preferred stock
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	94
Fair value	118
Amount at which shown in the Balance Sheet	118
Equity securities
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	3,692
Fair value	4,104
Amount at which shown in the Balance Sheet	4,104
Mortgage loans on real estate
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	4,188
Fair value	4,446
Amount at which shown in the Balance Sheet	4,188
Real estate
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	113
Amount at which shown in the Balance Sheet	113
Real estate acquired in satisfaction of debt
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	5
Amount at which shown in the Balance Sheet	5
Policy loans
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	909
Amount at which shown in the Balance Sheet	909
Derivative instruments
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	89
Fair value	92
Amount at which shown in the Balance Sheet	92
Limited partnership interests
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	4,527
Amount at which shown in the Balance Sheet	4,527
Other long-term investments
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	2,200
Amount at which shown in the Balance Sheet	2,200
Short-term investments
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	2,540
Fair value	2,540
Amount at which shown in the Balance Sheet	$ 2,540