Segment Information (Operating Results) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Segment Reporting Information [Line Items]
Pre-tax adjusted earnings	$ 843	$ (594)
Provision for income tax expense (benefit)	172	(141)
Post-tax adjusted earnings	671	(453)
Less: Net income (loss) attributable to noncontrolling interests	0	0
Net investment gains (losses)	(67)	12
Net derivative gains (losses)	555	(1,387)
Other adjustments to net income (loss)	112	96
Net income (loss) attributable to Brighthouse Life Insurance Company	671	(453)
Annuities
Segment Reporting Information [Line Items]
Interest revenue	553	547
Interest expense	0	0
Life
Segment Reporting Information [Line Items]
Interest revenue	140	150
Interest expense	0	0
Run-off
Segment Reporting Information [Line Items]
Interest revenue	401	463
Interest expense	0	0
Corporate & Other
Segment Reporting Information [Line Items]
Interest revenue	47	14
Interest expense	17	17
Operating Segments
Segment Reporting Information [Line Items]
Pre-tax adjusted earnings	393	556
Provision for income tax expense (benefit)	78	101
Post-tax adjusted earnings	315	455
Less: Net income (loss) attributable to noncontrolling interests	0	0
Adjusted earnings	315	455
Operating Segments | Annuities
Segment Reporting Information [Line Items]
Pre-tax adjusted earnings	374	396
Provision for income tax expense (benefit)	71	75
Post-tax adjusted earnings	303	321
Less: Net income (loss) attributable to noncontrolling interests	0	0
Adjusted earnings	303	321
Operating Segments | Life
Segment Reporting Information [Line Items]
Pre-tax adjusted earnings	39	141
Provision for income tax expense (benefit)	8	29
Post-tax adjusted earnings	31	112
Less: Net income (loss) attributable to noncontrolling interests	0	0
Adjusted earnings	31	112
Operating Segments | Run-off
Segment Reporting Information [Line Items]
Pre-tax adjusted earnings	19	85
Provision for income tax expense (benefit)	4	9
Post-tax adjusted earnings	15	76
Less: Net income (loss) attributable to noncontrolling interests	0	0
Adjusted earnings	15	76
Operating Segments | Corporate & Other
Segment Reporting Information [Line Items]
Pre-tax adjusted earnings	(39)	(66)
Provision for income tax expense (benefit)	(5)	(12)
Post-tax adjusted earnings	(34)	(54)
Less: Net income (loss) attributable to noncontrolling interests	0	0
Adjusted earnings	(34)	(54)
Segment Reconciling Items
Segment Reporting Information [Line Items]
Provision for income tax expense (benefit)	(94)	242
Net investment gains (losses)	(67)	12
Net derivative gains (losses)	555	(1,387)
Other adjustments to net income (loss)	$ (38)	$ 225