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Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Dispositions - Separation of Brighthouse - Income Statement (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations, net of income tax	$ 0	$ 0	$ (986)
Brighthouse Financial, Inc
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Other Income			150
Disposal Group, Including Discontinued Operation, Revenue			3,845
Disposal Group, Including Discontinued Operation, Other Expenses			853
Disposal Group, Including Discontinued Operation, Operating Expenses			3,706
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax			139
Discontinued Operation, Tax Effect of Discontinued Operation			(46)
Income (loss) from discontinued operations before loss on disposal of discontinued operations, net of income tax			185
Discontinued Operation, Separation cost, net			(216)
Tax charges associated with the Separation			(955)
Income (loss) on disposal of discontinued operations, net of income tax			(1,171)
Income (loss) from discontinued operations, net of income tax			(986)
Brighthouse Financial, Inc \| Premiums
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue			820
Brighthouse Financial, Inc \| Universal life and investment-type product policy fees
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue			2,201
Brighthouse Financial, Inc \| Net investment income
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue			1,783
Brighthouse Financial, Inc \| Total net investment gains (losses)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue			(48)
Brighthouse Financial, Inc \| Net derivative gains (losses)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue			(1,061)
Brighthouse Financial, Inc \| Policyholder benefits and claims
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Operating Expenses			2,217
Brighthouse Financial, Inc \| Interest credited to policyholder account balances
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Operating Expenses			620
Brighthouse Financial, Inc \| Policyholder dividend expense
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Operating Expenses			$ 16