Equity (Reclassifications Out of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)	$ (64)	$ (33)	$ (131)	$ (21)
Net investment income	1,044	1,196	2,179	2,365
Net derivative gains (losses)	1,762	(718)	2,317	(2,105)
Pre-tax adjusted earnings	1,225	(31)	2,068	(625)
Income tax (expense) benefit	(224)	23	(396)	164
Net income (loss) attributable to Brighthouse Life Insurance Company	1,000	(9)	1,671	(462)
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income (loss) attributable to Brighthouse Life Insurance Company	(44)	(22)	(75)	(7)
Reclassification out of Accumulated Other Comprehensive Income | Net unrealized investment gains (losses):
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)	(58)	(31)	(97)	(16)
Net derivative gains (losses)	(3)	1	(5)	(2)
Pre-tax adjusted earnings	(61)	(30)	(102)	(18)
Income tax (expense) benefit	12	7	21	4
Net income (loss) attributable to Brighthouse Life Insurance Company	(49)	(23)	(81)	(14)
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Pre-tax adjusted earnings	5	2	7	9
Income tax (expense) benefit	0	(1)	(1)	(2)
Net income (loss) attributable to Brighthouse Life Insurance Company	5	1	6	7
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Interest rate swaps
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment income	1	1	2	2
Net derivative gains (losses)	3	0	4	1
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Foreign currency swaps
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net derivative gains (losses)	$ 1	$ 1	$ 1	$ 6