Income Tax (Reconciliation of Income Tax Provision between US Statutory Rate and As Reported for Continuing Operations) (Details) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Deferred Income Tax Liabilities, Net	$ 9,032	$ 5,414		$ 9,032	$ 5,414
Income tax expense benefit continuing operations income tax reconciliation
Tax provision at U.S. statutory rate				1,427	1,325	$ 1,238
Dividend received deduction				(37)	(35)	(67)
Tax-exempt income				(64)	(29)	(97)
Prior year tax (1)				(179)	(197)	(27)
Low income housing tax credits				(254)	(284)	(278)
Other tax credits				(52)	(79)	(102)
Foreign tax rate differential				395	335	(95)
Change in valuation allowance				(22)	(2)	(8)
Other, net (8)				(2)	67	25
Deferred Federal Income Tax Expense (Benefit)				(235)	342	(2,373)
Provision for income tax expense (benefit)				886	1,179	(1,470)
MetLife Hong Kong
Income tax expense benefit continuing operations income tax reconciliation
Foreign tax rate differential				61
Brighthouse Financial, Inc
Income tax expense benefit continuing operations income tax reconciliation
Other, net (8)					69
Impact of Separation
Income tax expense benefit continuing operations income tax reconciliation
Other Adjustments, Amount				0	0	(540)
Provision for income tax expense (benefit)						(927)
Foreign dividends [Member]
Income tax expense benefit continuing operations income tax reconciliation
Tax benefit on dividends from non-us operations						264
Impact of U.S. Tax Reform
Income tax expense benefit continuing operations income tax reconciliation
Tax provision at U.S. statutory rate					12	(101)
Other Adjustments, Amount				(326)	78	(1,519)
Deferred Federal Income Tax Expense (Benefit)				(9)	(402)	(1,790)
Provision for income tax expense (benefit)				(326)	66	(1,620)
Alternative Minimum Tax Credits
Income tax expense benefit continuing operations income tax reconciliation
Deferred Federal Income Tax Expense (Benefit)				9	0	9
Tax Rate Change [Member]
Income tax expense benefit continuing operations income tax reconciliation
Other Adjustments, Amount					390
Patient Protection and Affordable Care Act excise tax [Member]
Income tax expense benefit continuing operations income tax reconciliation
Other, net (8)					18
Settlement with Taxing Authority
Income tax expense benefit continuing operations income tax reconciliation
Prior year tax (1)				158	168
Provision for income tax expense (benefit)	$ (158)	$ (168)
GILTI [Member] | Impact of U.S. Tax Reform
Income tax expense benefit continuing operations income tax reconciliation
Effective Income Tax Rate Reconciliation, Tax Contingency, Foreign, Amount				12
Provision for income tax expense (benefit)				35	45
Foreign Tax Authority
Income tax expense benefit continuing operations income tax reconciliation
Undistributed Earnings of Foreign Subsidiaries						3,000
Repatriation of Foreign Earnings						444
Foreign Tax Authority | Foreign dividends [Member]
Income tax expense benefit continuing operations income tax reconciliation
Foreign tax rate differential						180
Foreign Tax Authority | Impact of U.S. Tax Reform
Income tax expense benefit continuing operations income tax reconciliation
Other Adjustments, Amount			$ 180			170
Repatriation of Foreign Earnings				317	468	$ 350
CHILE
Income tax expense benefit continuing operations income tax reconciliation
Foreign tax rate differential					17
UNITED KINGDOM
Income tax expense benefit continuing operations income tax reconciliation
Other, net (8)					36
ARGENTINA
Income tax expense benefit continuing operations income tax reconciliation
Foreign tax rate differential					$ 13
Change in Accounting Method Accounted for as Change in Estimate [Member] | GILTI [Member] | Impact of U.S. Tax Reform
Income tax expense benefit continuing operations income tax reconciliation
Provision for income tax expense (benefit)				$ (23)