Segment Information Level 4 (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)
Segment Reporting Information [Line Items]
Number of company reporting segments			6
Segment Reporting Information, Operating Income (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 413	$ (467)	$ 880	$ 28
Net Income (Loss) Attributable to Parent	413	(467)	880	28
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	3,860	3,821	7,641	7,619
Insurance Commissions and Fees	469	502	928	998
Net Investment Income (Loss)	796	768	1,605	1,592
Total Realized Investment Gains (Losses)	9	(4)	14	(39)
Other Income	20	31	42	56
Revenues	4,685	4,616	9,302	9,228
Property and Casualty, Commercial Insurance Product Line [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	259	199	499	441
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	1,623	1,559	3,206	3,100
Property and Casualty, Personal Insurance Product Line [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	41	(30)	117	69
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	966	946	1,918	1,874
Affinity Earned Premiums	785	755	1,600	1,500
Property & Casualty Other Operations [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	(111)	(144)	(88)	(122)
Group Insurance Policies [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	56	55	108	106
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	796	777	1,576	1,576
Mutual Funds [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	22	21	44	42
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	184	183	363	357
Talcott Resolution [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	217	(504)	328	(359)
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	288	352	573	705
Corporate Segment [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	(71)	(64)	(128)	(149)
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Insurance Commissions and Fees	3	4	5	7
Non Proprietary [Member] \| Mutual Funds [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	154	148	303	286
Accident and Health Insurance Product Line [Member] \| Property and Casualty, Commercial Insurance Product Line [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	760	734	1,504	1,466
Accident and Health Insurance Product Line [Member] \| Group Insurance Policies [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	374	365	745	734
Property Insurance Product Line [Member] \| Property and Casualty, Commercial Insurance Product Line [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	160	137	316	273
Automobiles Commercial [Member] \| Property and Casualty, Commercial Insurance Product Line [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	152	145	300	289
Package Business [Member] \| Property and Casualty, Commercial Insurance Product Line [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	299	289	591	572
Liability [Member] \| Property and Casualty, Commercial Insurance Product Line [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	142	146	277	291
Surety Product Line [Member] \| Property and Casualty, Commercial Insurance Product Line [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	55	52	108	103
Professional Liability [Member] \| Property and Casualty, Commercial Insurance Product Line [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	55	56	110	106
Automobiles Consumer [Member] \| Property and Casualty, Personal Insurance Product Line [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	665	650	1,320	1,286
Homeowners [Member] \| Property and Casualty, Personal Insurance Product Line [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	301	296	598	588
Life Insurance Product Line [Member] \| Group Insurance Policies [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	376	371	741	759
Property & Casualty Other Operations [Member] \| Group Insurance Policies [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	46	41	90	83
Proprietary [Member] \| Mutual Funds [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Earned premiums and fee income	$ 30	$ 35	$ 60	$ 71

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Income from agency and brokerage operations (includes sales of annuities and supplemental contracts); service charges, commissions, and fees from the sale of insurance and related services; and management fees from separate accounts, deferred annuities, and universal life products.

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