Dispositions - Disposition of MetLife Afore (Details) - MetLife Afore $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Gross Profit (Loss)	$ (98)
Income (loss) on disposal of discontinued operations, net of income tax	(73)
Disposal Group, Including Discontinued Operation, Goodwill	$ 16

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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