Dispositions - Separation of Brighthouse - Transactions Prior to Separation (Details) - USD ($) $ in Millions		1 Months Ended		12 Months Ended
	Aug. 03, 2017	Jun. 30, 2017	Apr. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Aug. 02, 2017	Jul. 21, 2017
Debt Instrument [Line Items]
Secured Debt				$ 1,121	$ 1,274
Preferred Stock, Shares Issued				25,500,000	25,500,000
Preferred stock issued, net of issuance costs				$ 0	$ 0	$ 1,483
Debt Instrument, Face Amount				3,200	3,200
Brighthouse Financial, Inc [Member]
Debt Instrument [Line Items]
Cash Dividends Paid to Parent Company by Consolidated Subsidiaries	$ 1,800
Line of Credit Facility, Maximum Borrowing Capacity		$ 536	$ 3,000					$ 600
Line of Credit Facility, Current Borrowing Capacity								$ 500
Payments of Distributions to Affiliates			590
Preferred Stock, Shares Issued		50,000
Preferred Stock, Dividend Payment Rate, Variable		0.065
Preferred stock issued, net of issuance costs		$ 49
Debt Instrument, Face Amount							$ 500
Brighthouse Financial, Inc [Member] | 2027 Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 1,500
Debt Instrument, Maturity Date		Jun. 30, 2027
Debt Instrument, Interest Rate, Stated Percentage		3.70%
Brighthouse Financial, Inc [Member] | 2047 Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 1,500
Debt Instrument, Maturity Date		Jun. 30, 2047
Debt Instrument, Interest Rate, Stated Percentage		4.70%
Brighthouse Financial, Inc [Member] | MetLife Reinsurance Company Of South Carolina | Secured Debt [Member]
Debt Instrument [Line Items]
Other General and Administrative Expense			37
Invested Assets On Deposit Held In Trust And Pledged As Collateral			2,800
Secured Debt			2,800
Brighthouse Financial, Inc [Member] | Brighthouse Reinsurance Company of Delaware [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			10,000
Committed Credit Facility Five [Member] | Brighthouse Financial, Inc [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			3,500
Committed Credit Facility Seven [Member] | Brighthouse Financial, Inc [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			4,300
Committed Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				3,700
Line of Credit Facility, Commitment Fee Amount				21	27	29
Committed Credit Facility [Member] | Brighthouse Financial, Inc [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Amount			$ 257	$ 305	$ 69	$ 61