Basis of Presentation and Accounting Policies Level 1 (Notes)	3 Months Ended
	Mar. 31, 2016
Accounting Policies [Abstract]
Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block]	Basis of Presentation and Significant Accounting Policies
Basis of Presentation and Accounting Policies	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 to individual and business customers in the United States (collectively, “The Hartford”, the “Company”, “we” or “our”). Also, the Company continues to runoff life and annuity products previously sold. On March 16, 2016, the Company announced it had entered into a definitive agreement for its wholly-owned subsidiary, Hartford Fire Insurance Company, to purchase Northern Homelands Company, the holding company of Maxum Specialty Insurance Group headquartered in Alpharetta, Georgia for $170, subject to post closing adjustments. Maxum will maintain its brand and limited wholesale distribution model and will be managed as a separate unit within The Hartford's Small Commercial line of business. The transaction, which will not have a material impact on the Company's financial position, results of operations or cashflows, is expected to close in the third quarter of 2016, subject to regulatory approvals. 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 2015 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 2015 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 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; evaluation of other-than-temporary impairments on available-for-sale securities and valuation allowances on investments; living benefits required to be fair valued; evaluation of goodwill for impairment; valuation of investments and derivative instruments; 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 period financial information to conform to the current period presentation. Adoption of New Accounting Standards On January 1, 2016 the Company adopted new consolidation guidance issued by the Financial Accounting Standards Board (“FASB”). The updates revise when to consolidate variable interest entities ("VIEs") and general partners’ investments in limited partnerships, end the deferral granted for applying the VIE guidance to certain investment companies, and reduce the number of circumstances where a decision maker’s or service provider’s fee arrangement is deemed to be a variable interest in an entity. The updates also modify guidance for determining whether limited partnerships are VIEs or voting interest entities. The new guidance did not have a material effect on the Company’s Condensed Consolidated Financial Statements though one investment in a hedge fund of funds that was previously consolidated as a voting interest entity is now consolidated as a VIE. For further discussion, see Note 5 - Investments and Derivative Instruments of Notes to Condensed Consolidated Financial Statements. Future Adoption of New Accounting Standards Leases In February 2016, the FASB issued updated guidance on lease accounting. Under the new guidance, lessees with operating leases will be required to recognize a liability for the present value of future minimum lease payments with a corresponding asset for the right of use of the property. Under existing guidance, future minimum lease payments on operating leases are commitments that are not recognized as liabilities on the balance sheet. The updated guidance is to be adopted effective January 1, 2019 through a cumulative effect adjustment to retained earnings for the earliest period presented, with early application permitted. Leases will be classified as financing or operating leases similar to capital and operating leases, respectively, under current accounting guidance. Where the lease is economically similar to a purchase because The Hartford obtains control of the underlying asset, the lease will be a financing lease and the Company will recognize amortization of the right of use asset and interest expense on the liability. Where the lease provides The Hartford with only the right to control the use of the underlying asset over the lease term and the lease term is greater than one year, the lease will be an operating lease and the amortization and interest cost will be recognized as rental expense over the lease term on a straight-line basis. Leases with a term of one year or less will also be expensed over the lease term but will not be recognized on the balance sheet. The Company is currently evaluating the potential impact of the new guidance to the consolidated financial statements, including the timing of adoption. We do not expect a material impact to the consolidated financial statements; however, it is expected that assets and liabilities will increase based on the present value of remaining lease payments for leases in place at the adoption date. Stock Compensation In March 2016, the FASB issued updated guidance on accounting for share-based payments to employees. The updated guidance requires the excess tax benefit or deficiency on vesting or settlement of awards to be recognized in earnings as an income tax benefit or expense, respectively. This recognition of excess tax benefits and deficiencies will result in earnings volatility as current accounting guidance recognizes these amounts as an adjustment to additional paid-in capital. The excess tax benefit was $27 and $6 for the years ended December 31, 2015 and 2014, respectively, which would have increased net income in each of those years. The excess tax benefits or deficiencies are discrete items in the reporting period in which they occur, and so will not be considered in determining the annual estimated effective tax rate. The excess tax benefits or deficiencies will be presented as a cash flow within operating activities instead of within financing activities as is the case under current accounting. The Hartford will adopt the updated guidance January 1, 2017 and will recognize excess tax benefits or deficiencies in net income, as well as the related cash flows in operating activities, on a prospective basis. The impact of the adoption will depend on the excess tax benefits or deficiencies realized on vesting or settlement of awards resulting from the difference between the market value of awards at vesting or settlement and the grant date fair value recognized through compensation expense.