Separation of Brighthouse (Income Statement) (Details) $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax	$ (182)
Discontinued Operation, Tax Effect of Discontinued Operation	(106)
Income (loss) from discontinued operations before loss on disposal of discontinued operations, net of income tax	(76)
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	32
Disposal Group, Including Discontinued Operation, Revenue	1,349
Disposal Group, Including Discontinued Operation, Other Expense	261
Disposal Group, Including Discontinued Operation, Operating Expenses	1,531
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	350
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	942
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	775
Brighthouse Financial, Inc \| Gain (Loss) on Investments
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue	(50)
Brighthouse Financial, Inc \| Gain (Loss) on Derivative Instruments
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue	(700)
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	1,002
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	261
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	7
Brighthouse Financial, Inc \| Goodwill impairment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Operating Expenses	$ 0

Income (loss) from discontinued operations, net of tax, before loss on disposal of discontinued operations

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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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