Basis of Presentation and Accounting Policies Level 2 (Policies)	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies [Text Block]	The Hartford Financial Services Group, Inc. is a holding company for insurance and financial services subsidiaries that provide property and casualty insurance, group life and disability products and mutual funds and exchange-traded products to individual and business customers in the United States (collectively, “The Hartford”, the “Company”, “we” or “our”). Also, the Company continues to run off life and annuity products previously sold. On July 26, 2016, the Company announced the signing of a definitive agreement to sell its United Kingdom ("U.K.") property and casualty run-off subsidiaries. For discussion of this transaction, see Note 2 - Business Disposition of Notes to Condensed Consolidated Financial Statements. The Condensed Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) for interim financial information, which differ materially from the accounting practices prescribed by various insurance regulatory authorities. These Condensed Consolidated Financial Statements and Notes should be read in conjunction with the Consolidated Financial Statements and Notes thereto included in the Company's 2016 Form 10-K Annual Report. The results of operations for interim periods are not necessarily indicative of the results that may be expected for the full year. The accompanying Condensed Consolidated Financial Statements and Notes are unaudited. These financial statements reflect all adjustments (generally consisting only of normal accruals) which are, in the opinion of management, necessary for the fair presentation of the financial position, results of operations and cash flows for the interim periods. The Company's significant accounting policies are summarized in Note 1 - Basis of Presentation and Significant Accounting Policies of Notes to Consolidated Financial Statements included in the Company's 2016 Form 10-K Annual Report. Consolidation The Condensed Consolidated Financial Statements include the accounts of The Hartford Financial Services Group, Inc., and entities in which the Company directly or indirectly has a controlling financial interest. Entities in which the Company has significant influence over the operating and financing decisions but does not control are reported using the equity method. All intercompany transactions and balances between The Hartford and its subsidiaries and affiliates have been eliminated. Use of Estimates The preparation of financial statements, in conformity with U.S. GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. The most significant estimates include those used in determining property and casualty and group long-term disability (LTD) insurance product reserves, net of reinsurance; estimated gross profits used in the valuation and amortization of assets and liabilities associated with variable annuity and other universal life-type contracts; living benefits required to be fair valued; evaluation of goodwill for impairment; valuation of investments and derivative instruments, including evaluation of other-than-temporary impairments on available-for-sale securities and valuation allowances on mortgage loans; valuation allowance on deferred tax assets; and contingencies relating to corporate litigation and regulatory matters. Certain of these estimates are particularly sensitive to market conditions, and deterioration and/or volatility in the worldwide debt or equity markets could have a material impact on the Condensed Consolidated Financial Statements. Reclassifications Certain reclassifications have been made to prior year financial information to conform to the current year presentation. In particular, billing installment fees that were previously reflected as an offset to insurance operating costs and other expenses are now classified as revenues. Adoption of New Accounting Standards Stock Compensation On January 1, 2017 the Company adopted new stock compensation guidance issued by the Financial Accounting Standards Board ("FASB") on a prospective basis. The updated guidance requires the excess tax benefit or tax deficiency on vesting or settlement of stock-based awards to be recognized in earnings as an income tax benefit or expense, respectively, instead of as an adjustment to additional paid-in capital. The new guidance also requires the related cash flows to be presented in operating activities instead of in financing activities. The amount of excess tax benefit or tax deficiency realized on vesting or settlement of awards depends upon the difference between the market value of awards at vesting or settlement and the grant date fair value recognized through compensation expense. The excess tax benefit or tax deficiency is a discrete item in the reporting period in which it occurs and is not considered in determining the annual estimated effective tax rate for interim reporting. The excess tax benefit recognized in earnings for the three months ended March 31, 2017 was $7 and the excess tax benefit recognized in additional paid in capital for the three months ended March 31, 2016 was $24.
Basis of Presentation	The Hartford Financial Services Group, Inc. is a holding company for insurance and financial services subsidiaries that provide property and casualty insurance, group life and disability products and mutual funds and exchange-traded products to individual and business customers in the United States (collectively, “The Hartford”, the “Company”, “we” or “our”). Also, the Company continues to run off life and annuity products previously sold. On July 26, 2016, the Company announced the signing of a definitive agreement to sell its United Kingdom ("U.K.") property and casualty run-off subsidiaries. For discussion of this transaction, see Note 2 - Business Disposition of Notes to Condensed Consolidated Financial Statements. The Condensed Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) for interim financial information, which differ materially from the accounting practices prescribed by various insurance regulatory authorities. These Condensed Consolidated Financial Statements and Notes should be read in conjunction with the Consolidated Financial Statements and Notes thereto included in the Company's 2016 Form 10-K Annual Report. The results of operations for interim periods are not necessarily indicative of the results that may be expected for the full year. The accompanying Condensed Consolidated Financial Statements and Notes are unaudited. These financial statements reflect all adjustments (generally consisting only of normal accruals) which are, in the opinion of management, necessary for the fair presentation of the financial position, results of operations and cash flows for the interim periods. The Company's significant accounting policies are summarized in Note 1 - Basis of Presentation and Significant Accounting Policies of Notes to Consolidated Financial Statements included in the Company's 2016 Form 10-K Annual Report.
Consolidation	Consolidation The Condensed Consolidated Financial Statements include the accounts of The Hartford Financial Services Group, Inc., and entities in which the Company directly or indirectly has a controlling financial interest. Entities in which the Company has significant influence over the operating and financing decisions but does not control are reported using the equity method. All intercompany transactions and balances between The Hartford and its subsidiaries and affiliates have been eliminated.
Use of Estimates	Use of Estimates The preparation of financial statements, in conformity with U.S. GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. The most significant estimates include those used in determining property and casualty and group long-term disability (LTD) insurance product reserves, net of reinsurance; estimated gross profits used in the valuation and amortization of assets and liabilities associated with variable annuity and other universal life-type contracts; living benefits required to be fair valued; evaluation of goodwill for impairment; valuation of investments and derivative instruments, including evaluation of other-than-temporary impairments on available-for-sale securities and valuation allowances on mortgage loans; valuation allowance on deferred tax assets; and contingencies relating to corporate litigation and regulatory matters. Certain of these estimates are particularly sensitive to market conditions, and deterioration and/or volatility in the worldwide debt or equity markets could have a material impact on the Condensed Consolidated Financial Statements.
Reclassification, Policy	Reclassifications Certain reclassifications have been made to prior year financial information to conform to the current year presentation. In particular, billing installment fees that were previously reflected as an offset to insurance operating costs and other expenses are now classified as revenues.