Separation of Brighthouse (Income Statement) (Details) - Brighthouse Financial, Inc - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Other Income	$ 90	$ 122
Disposal Group, Including Discontinued Operation, Revenue	1,959	3,308
Disposal Group, Including Discontinued Operation, Other Expense	776	1,037
Disposal Group, Including Discontinued Operation, Operating Expenses	1,934	3,465
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax	25	(157)
Discontinued Operation, Tax Effect of Discontinued Operation	(33)	(139)
Income (loss) from discontinued operations before loss on disposal of discontinued operations, net of income tax	58	(18)
Premiums
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue	355	705
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	938	1,880
Net investment income
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue	766	1,541
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	0	(50)
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	(190)	(890)
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	881	1,883
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	270	531
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	$ 14

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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