Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Mar. 21, 2018
Document and Entity Information [Abstract]
Entity Registrant Name	Brighthouse Life Insurance Company
Entity Central Index Key	0000733076
Document Type	10-K
Document Period End Date	Dec. 31, 2017
Amendment Flag	false
Entity Current Reporting Status	Yes
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Filer Category	Non-accelerated Filer
Entity Public Float	$ 0
Entity Common Stock, Shares Outstanding		3,000