Basis of Presentation and Accounting Policies (Details) - USD ($) $ in Millions		1 Months Ended	2 Months Ended	3 Months Ended	5 Months Ended	6 Months Ended
	Jan. 01, 2018	Jun. 30, 2018	May 31, 2018	Jun. 30, 2017	May 31, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 01, 2018	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Sale of HHI		On May 31, 2018 the Company's indirect parent, Hartford Holding, Inc. ("HHI") completed the sale of the Company's parent to a group of investors led by Cornell Capital LLC, Atlas Merchant Capital LLC, TRB Advisors LP, Global Atlantic Financial Group ("Global Atlantic"), Pine Brook and J. Safra Group. Although Talcott Resolution Life Insurance Company is no longer affiliated with The Hartford Financial Services Group, Inc. ("The Hartford") or any of its subsidiaries, The Hartford retained a 9.7 percent ownership interest in HHLP. On June 1, 2018, TL executed reinsurance agreements to reinsure certain fixed immediate and deferred annuity contracts, variable payout separate account annuity contracts, standard mortality structured settlements, and period certain structured settlement annuity contracts to Commonwealth Annuity and Life Insurance Company ("Commonwealth"), a subsidiary of Global Atlantic which is a member of the acquiring investment group. TL reinsured an 85% quota share, except 75% for standard mortality structured settlements, in exchange for a $357 ceding commission that was fixed based on reinsuring approximately $9.3 billion of reserves as of December 31, 2016, plus annuitizations through closing and annuitizations from market value adjusted annuities post-close. The reinsurance agreement was executed after the Talcott Acquisition Date and as such, the accounting for the agreement was recorded after the TL balance sheet was adjusted to fair value in purchase and pushdown accounting. A deferred gain of $1 billion was recorded in Other liabilities on the Condensed Consolidated Balance Sheet related to this reinsurance agreement and will be amortized over the life of the underlying policies reinsured.
Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings						$ 193
Equity securities, available-for-sale, at fair value (cost of $0 and $140)		$ 0				0				$ 154
Fee income and other		72	$ 150	$ 225	$ 381		$ 446
Investments and Cash								$ 27,038
Present Value of Future Insurance Profits, Net		798	0	0	0	798	0	805		0		$ 0
Deferred Income Tax Assets, Net		1,003				1,003		998		556
Intangible Assets, Net (Excluding Goodwill)		54				54		55		0
Reinsurance Recoverables, Including Reinsurance Premium Paid		30,132				30,132		22,615		20,785
Separate Account Assets		109,595				109,595		110,773		115,834
Assets		162,215				162,215		162,284		168,732
Liability for Future Policy Benefits		18,299				18,299		18,057		14,482
Policyholder Funds		29,400				29,400		29,560		29,228
Other Liabilities		3,170				3,170		2,127		2,508
Separate Accounts, Liability		109,595				109,595		110,773		115,834
Liabilities		160,464				160,464		160,517		162,052
Stockholders' Equity Attributable to Parent		1,751	5,810	7,906	5,810	1,751	7,906	1,767		6,680
Liabilities and Equity		162,215				162,215		162,284		168,732
Fee Income [Member] | Other fee revenues [Member]
Fee income and other		8	16	13	40		27
Equity Securities [Member]
Equity securities, available-for-sale, at fair value (cost of $0 and $140)		154				154				154
Accumulated Net Unrealized Investment Gain (Loss)
OCI, before Reclassifications	$ 11	(75)	(131)	187
Stockholders' Equity Attributable to Parent		$ (75)	$ 774	$ 899	$ 774	$ (75)	$ 899	$ 0	$ 900	$ 1,022	$ 737	$ 693