Segment Information Level 4 (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Number of Reportable Segments									6
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									$ 13,336,000,000	$ 13,231,000,000	$ 13,637,000,000
earned premium, fee income and other considerations									15,332,000,000	15,336,000,000	17,204,000,000
Insurance Commissions and Fees									1,996,000,000	2,105,000,000	3,567,000,000
Total net investment income									3,154,000,000	3,264,000,000	4,127,000,000
Net realized capital losses									16,000,000	1,798,000,000	497,000,000
Other revenues									112,000,000	275,000,000	258,000,000
Segments, Geographical Areas [Abstract]
Revenues	4,617,000,000	4,769,000,000	4,616,000,000	4,612,000,000	4,777,000,000	4,862,000,000	4,734,000,000	6,300,000,000	18,614,000,000	20,673,000,000	22,086,000,000
Segment Reporting Information, Profit (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest									798,000,000	176,000,000	(38,000,000)
Segment Reporting Information, Income (Loss) before Income Taxes [Abstract]
Income Tax Expense (Benefit)									350,000,000	246,000,000	(309,000,000)
Assets by Segment [Abstract]
Assets	245,013,000,000				277,884,000,000				245,013,000,000	277,884,000,000
Proprietary [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Fees and Commissions									137,000,000	148,000,000	207,000,000
Non Proprietary [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Fees and Commissions									586,000,000	520,000,000	419,000,000
Other Group Benefit [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									167,000,000	161,000,000	194,000,000
Group Life and Accident [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									1,478,000,000	1,717,000,000	1,881,000,000
Group Disability [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									1,450,000,000	1,452,000,000	1,735,000,000
Homeowners [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									1,193,000,000	1,138,000,000	1,110,000,000
Automobiles Consumer [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									2,613,000,000	2,522,000,000	2,526,000,000
Professional Liability [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									213,000,000	222,000,000	253,000,000
Fidelity and Surety [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									210,000,000	201,000,000	205,000,000
Liability [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									582,000,000	566,000,000	562,000,000
Package Business [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									1,163,000,000	1,139,000,000	1,160,000,000
Property Insurance Product Line [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									559,000,000	521,000,000	505,000,000
Automobiles Commercial [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									591,000,000	579,000,000	587,000,000
Workers Compensation [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									2,971,000,000	2,975,000,000	2,987,000,000
Available-for-sale Securities [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Total net investment income									3,153,000,000	3,263,000,000	4,126,000,000
Equity Securities [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Total net investment income									1,000,000	1,000,000	1,000,000
Property & Casualty Commercial [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									6,289,000,000	6,203,000,000	6,259,000,000
Segment Reporting Information, Profit (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest									983,000,000	870,000,000	547,000,000
Deferred Policy Acquisition Costs Disclosures [Abstract]
Amortization of deferred policy acquisition costs and present value of future profits									919,000,000	905,000,000	927,000,000
Segment Reporting Information, Income (Loss) before Income Taxes [Abstract]
Income Tax Expense (Benefit)									385,000,000	320,000,000	159,000,000
Assets by Segment [Abstract]
Assets	28,451,000,000				27,119,000,000				28,451,000,000	27,119,000,000
Property and Casualty, Personal Insurance Product Line [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									3,806,000,000	3,660,000,000	3,636,000,000
Segment Information (Textual) [Abstract]
AARP earned premiums									3,000,000,000	2,900,000,000	2,800,000,000
Segment Reporting Information, Profit (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest									207,000,000	229,000,000	166,000,000
Deferred Policy Acquisition Costs Disclosures [Abstract]
Amortization of deferred policy acquisition costs and present value of future profits									348,000,000	332,000,000	332,000,000
Segment Reporting Information, Income (Loss) before Income Taxes [Abstract]
Income Tax Expense (Benefit)									92,000,000	100,000,000	65,000,000
Assets by Segment [Abstract]
Assets	5,983,000,000				5,873,000,000				5,983,000,000	5,873,000,000
Property and Casualty Other Operations [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									1,000,000	1,000,000	(2,000,000)
Segment Reporting Information, Income (Loss) before Income Taxes [Abstract]
Income Tax Expense (Benefit)									(51,000,000)	(20,000,000)	14,000,000
Assets by Segment [Abstract]
Assets	4,328,000,000				4,331,000,000				4,328,000,000	4,331,000,000
Group Benefits [Member]
Deferred Policy Acquisition Costs Disclosures [Abstract]
Amortization of deferred policy acquisition costs and present value of future profits									32,000,000	33,000,000	33,000,000
Segment Reporting Information, Income (Loss) before Income Taxes [Abstract]
Income Tax Expense (Benefit)									63,000,000	63,000,000	31,000,000
Assets by Segment [Abstract]
Assets	9,686,000,000				8,882,000,000				9,686,000,000	8,882,000,000
Mutual Funds [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Fees and Commissions									723,000,000	668,000,000	626,000,000
Segment Reporting Information, Profit (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest									87,000,000	76,000,000	71,000,000
Deferred Policy Acquisition Costs Disclosures [Abstract]
Amortization of deferred policy acquisition costs and present value of future profits									28,000,000	39,000,000	35,000,000
Segment Reporting Information, Income (Loss) before Income Taxes [Abstract]
Income Tax Expense (Benefit)									49,000,000	42,000,000	38,000,000
Assets by Segment [Abstract]
Assets	443,000,000				307,000,000				443,000,000	307,000,000
Talcott Resolution [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
earned premium, fee income and other considerations									1,407,000,000	1,463,000,000	2,708,000,000
Segment Reporting Information, Profit (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest									(187,000,000)	(634,000,000)	1,000,000
Talcott Resolution [Member]
Deferred Policy Acquisition Costs Disclosures [Abstract]
Amortization of deferred policy acquisition costs and present value of future profits									402,000,000	485,000,000	663,000,000
Segment Reporting Information, Income (Loss) before Income Taxes [Abstract]
Income Tax Expense (Benefit)									16,000,000	(7,000,000)	(99,000,000)
Assets by Segment [Abstract]
Assets	191,801,000,000				222,269,000,000				191,801,000,000	222,269,000,000
Corporate [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Insurance Commissions and Fees									11,000,000	11,000,000	167,000,000
Segment Reporting Information, Profit (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest									(375,000,000)	(555,000,000)	(1,009,000,000)
Segment Reporting Information, Income (Loss) before Income Taxes [Abstract]
Income Tax Expense (Benefit)									(204,000,000)	(252,000,000)	(517,000,000)
Assets by Segment [Abstract]
Assets	4,321,000,000				9,103,000,000				4,321,000,000	9,103,000,000
Other Insurance Product Line [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest									(108,000,000)	(2,000,000)	57,000,000
Group Insurance Policies [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Premiums Earned, Net									3,095,000,000	3,330,000,000	3,810,000,000
Segment Reporting Information, Profit (Loss) [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest									$ 191,000,000	$ 192,000,000	$ 129,000,000