Business, Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details)	3 Months Ended
Mar. 31, 2018 Segment	Aug. 04, 2017 shares
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of segments \| Segment	5
Brighthouse Financial, Inc \| Impact of Separation [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Common Stock, Shares, Issued \| shares		96,776,670

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Period Type:	duration