Acquisitions and Dispositions Dispositions - Pending Disposition of MetLife Hong Kong (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Goodwill, Written off Related to Sale of Business Unit	$ 71	$ 16
MetLife Hong Kong
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax	(140)
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax	(100)
Goodwill, Written off Related to Sale of Business Unit	71
Discontinued Operation, Tax (Expense) Benefit from Provision for (Gain) Loss on Disposal	(40)
Disposal Group, Including Discontinued Operation, Assets	$ 2,900

Amount classified as assets attributable to disposal group held for sale or disposed of.

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