Document and Entity Information - USD ($)
9 Months Ended
Sep. 30, 2018
Nov. 02, 2018
Jun. 30, 2017
Document and Entity Information [Abstract]      
Entity Registrant Name BRIGHTHOUSE FINANCIAL, INC.    
Entity Central Index Key 0001685040    
Document Type 10-Q    
Document Period End Date Sep. 30, 2018    
Amendment Flag false    
Document Fiscal Year Focus 2018    
Document Fiscal Period Focus Q3    
Current Fiscal Year End Date --12-31    
Entity Current Reporting Status Yes    
Entity Small Business false    
Entity Emerging Growth Company false    
Entity Filer Category Non-accelerated Filer    
Entity Public Float     $ 0
Entity Common Stock, Shares Outstanding   118,601,232