Equity (Share-Based Compensation (Narrative) (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures	242,560
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	7,306,788
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 53.47
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	24,570
Other Share Based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 year 3 months
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 13,000,000
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance Factor	0.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance Factor	150.00%
Brighthouse Reinsurance Company of Delaware [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	$ 8,700,000,000	$ 8,300,000,000
Statutory Accounting Practices, Statutory Net Income Amount	(1,100,000,000)	(1,600,000,000)
Statutory Accounting Practices, Prescribed Practice, Amount	$ 557,000,000	$ 972,000,000

The percentage of the performance factor for the three year period used for perfomance shares and units.

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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.

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No definition available.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Net number of share options (or share units) granted during the period.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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- Definition

Amount as of the balance sheet date of each item listed to reconcile the differences resulting from applying state prescribed statutory accounting practices rather than statutory accounting practices prescribed by National Association of Insurance Commissioners.

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The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

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Amount of net income for the period determined using accounting principles prescribed or permitted by insurance regulators.

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- Definition

Number of share options (or share units) exercised during the current period.

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