Schedule I Summary of Investments - Other Than Investments in Affiliates Level 4 (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	$ 72,629
Fair Value	76,562
Amount which shown on Balance Sheet	76,278
Fixed Maturities [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	55,840
Fair Value	59,872
Amount which shown on Balance Sheet	59,872
Industrial, miscellaneous and all other [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	844
Fair Value	853
Amount which shown on Balance Sheet	853
Non-redeemable preferred stocks [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	183
Fair Value	194
Amount which shown on Balance Sheet	194
Equity securities, trading [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	10
Fair Value	11
Amount which shown on Balance Sheet	11
Equity Securities [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	1,037
Fair Value	1,058
Amount which shown on Balance Sheet	1,058
Mortgage loans [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	5,556
Fair Value	5,840
Amount which shown on Balance Sheet	5,556
Policy Loans [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	1,431
Fair Value	1,431
Amount which shown on Balance Sheet	1,431
Investments in partnerships and trusts [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	2,942
Fair Value	2,942
Amount which shown on Balance Sheet	2,942
Futures Options and Miscellaneous [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	940
Fair Value	536
Amount which shown on Balance Sheet	536
Short-term Investments [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	4,883
Fair Value	4,883
Amount which shown on Balance Sheet	4,883
Available-for-sale Securities [Member] \| Equity Securities [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	1,027
Fair Value	1,047
Amount which shown on Balance Sheet	1,047
Available-for-sale Securities [Member] \| Fixed Maturities [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	478
Fair Value	488
Amount which shown on Balance Sheet	488
Portion at Fair Value Measurement [Member] \| U.S. government and government agencies and authorities (guaranteed and sponsored) [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	7,135
Fair Value	7,596
Amount which shown on Balance Sheet	7,596
Portion at Fair Value Measurement [Member] \| US States and Political Subdivisions Debt Securities [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	11,735
Fair Value	12,871
Amount which shown on Balance Sheet	12,871
Portion at Fair Value Measurement [Member] \| Foreign governments [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	1,592
Fair Value	1,636
Amount which shown on Balance Sheet	1,636
Portion at Fair Value Measurement [Member] \| Public utilities [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	4,278
Fair Value	4,761
Amount which shown on Balance Sheet	4,761
Portion at Fair Value Measurement [Member] \| All other corporate bonds [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	20,910
Fair Value	22,598
Amount which shown on Balance Sheet	22,598
Portion at Fair Value Measurement [Member] \| All Other Mortgage Backed and Asset Backed Securities [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	9,712
Fair Value	9,922
Amount which shown on Balance Sheet	9,922
Portion at Fair Value Measurement [Member] \| Available-for-sale Securities [Member] \| Fixed Maturities [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	55,362
Fair Value	59,384
Amount which shown on Balance Sheet	$ 59,384

This element represents the carrying (reported) amount of the entity's investments as of the balance sheet date. This amount may represent the individual investment's or group of similar investments' original cost, fair value, or such other amount at which the investment is shown in the entity's balance sheet.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 15

-Article 12

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 320

-Section S99

-Paragraph 7

-Subparagraph (SX 210.12-15)

-URI http://asc.fasb.org/extlink&oid=34726532&loc=d3e611379-123010

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