Equity (Captive Equity and Income - Narrative) (Details) - Brighthouse Reinsurance Company of Delaware - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	$ 9,000	$ 8,700
Statutory Accounting Practices, Statutory Net Income Amount	(316)	(1,100)	$ (1,600)
Statutory Accounting Practices, Prescribed Practice, Amount	$ 572	$ 557