Earnings Per Common Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share [Abstract]
Net income (loss) available to Brighthouse Financial, Inc.’s common shareholders	$ (3,012)	$ 676	$ (60)	$ 316
Weighted average common shares outstanding - basic	92,693,188	110,915,416	97,366,447	114,195,767
Dilutive effect of share-based awards	0	612,064	0	546,931
Weighted average common shares outstanding - diluted	92,693,188	111,527,480	97,366,447	114,742,698
Earnings per common share - basic	$ (32.49)	$ 6.09	$ (0.61)	$ 2.77
Earnings per common share - diluted	$ (32.49)	$ 6.06	$ (0.61)	$ 2.75
Antidilutive stock options excluded from the computation of earnings per common share		196,492		196,492