SCHEDULE I - SUMMARY OF INVESTMENTS OTHER THAN INVESTMENTS IN RELATED PARTIES (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	$ 52,147
Amount at which shown in the Balance Sheet	55,866
United States government, government agencies and authorities
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	2,137
Fair value	2,379
Amount at which shown in the Balance Sheet	2,379
States, municipalities and political subdivisions
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	4,153
Fair value	4,704
Amount at which shown in the Balance Sheet	4,704
Foreign government
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	1,017
Fair value	1,180
Amount at which shown in the Balance Sheet	1,180
Public utilities
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	6,175
Fair value	6,934
Amount at which shown in the Balance Sheet	6,934
Convertibles and bonds with warrants attached
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	401
Fair value	358
Amount at which shown in the Balance Sheet	358
All other corporate bonds
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	22,172
Fair value	24,239
Amount at which shown in the Balance Sheet	24,239
Asset-backed securities
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	1,921
Fair value	1,865
Amount at which shown in the Balance Sheet	1,865
Residential mortgage-backed securities
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	1,778
Fair value	1,791
Amount at which shown in the Balance Sheet	1,791
Commercial mortgage-backed securities
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	1,425
Fair value	1,408
Amount at which shown in the Balance Sheet	1,408
Redeemable preferred stock
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	15
Fair value	18
Amount at which shown in the Balance Sheet	18
Fixed income securities
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	41,194
Fair value	44,876
Amount at which shown in the Balance Sheet	44,876
Industrial, miscellaneous and all other
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	310
Fair value	345
Amount at which shown in the Balance Sheet	345
Mortgage loans on real estate
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	5,943
Fair value	6,223
Amount at which shown in the Balance Sheet	5,943
Real estate investment
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	62
Amount at which shown in the Balance Sheet	62
Real estate acquired in satisfaction of debt
Summary of Investments Other Than Investments in Related Parties
Amount at which shown in the Balance Sheet	34
Policy loans
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	836
Amount at which shown in the Balance Sheet	836
Derivative instruments
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	127
Fair value	129
Amount at which shown in the Balance Sheet	129
Limited partnership interests
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	1,924
Amount at which shown in the Balance Sheet	1,924
Other long-term investments
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	876
Amount at which shown in the Balance Sheet	876
Short-term investments
Summary of Investments Other Than Investments in Related Parties
Cost/amortized cost	875
Fair value	875
Amount at which shown in the Balance Sheet	$ 875