Equity (Reclassifications Out of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)									$ (298)	$ (308)	$ 317
Net investment income									16,166	17,363	16,790
Net derivative gains (losses)									851	(590)	(690)
Income (loss) from discontinued operations, net of income tax	$ 0	$ 0	$ 0	$ 0	$ 0	$ (968)	$ 58	$ (76)	0	(986)	(2,734)
Other expenses									13,714	13,621	13,749
Income (loss) from continuing operations before provision for income tax									6,307	3,536	4,281
Income tax (expense) benefit									(1,179)	1,470	(693)
Net income (loss)	$ 2,062	$ 915	$ 894	$ 1,257	$ 2,315	$ (85)	$ 914	$ 876	5,128	4,020	854
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income (loss)									(484)	747	(293)
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Investment Gains (Losses), Net of Related Offsets
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)									6	404	78
Net investment income									(1)	20	39
Net derivative gains (losses)									(19)	(49)	(37)
Income (loss) from continuing operations before provision for income tax									(14)	289	(21)
Income tax (expense) benefit									3	(87)	9
Net income (loss)									(11)	202	(12)
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains (Losses) on Derivatives
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income (loss) from continuing operations before provision for income tax									(517)	1,025	(229)
Income tax (expense) benefit									135	(356)	66
Net income (loss)									(382)	669	(163)
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains (Losses) on Derivatives | Interest rate swaps
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment income									18	16	12
Net derivative gains (losses)									23	24	56
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains (Losses) on Derivatives | Interest rate forwards
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment income									2	2	4
Net derivative gains (losses)									(2)	(11)	(1)
Other expenses									1	1	1
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains (Losses) on Derivatives | Foreign currency swaps
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment income									(5)	0	(2)
Net derivative gains (losses)									(558)	974	(350)
Other expenses									2	2	2
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains (Losses) on Derivatives | Credit forwards
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment income									1	0	1
Net derivative gains (losses)									1	1	3
Reclassification out of Accumulated Other Comprehensive Income | Defined Benefit Plans Adjustment
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of net actuarial gains (losses)									(145)	(190)	(199)
Amortization of prior service (costs) credit									25	23	6
Income (loss) from continuing operations before provision for income tax									(120)	(167)	(193)
Income tax (expense) benefit									29	43	75
Net income (loss)									(91)	(124)	(118)
Brighthouse Financial, Inc
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)										(1,016)
Income (loss) from discontinued operations, net of income tax										(986)	(2,734)
Other expenses										(18)	59
Brighthouse Financial, Inc | Reclassification out of Accumulated Other Comprehensive Income | Unrealized Investment Gains (Losses), Net of Related Offsets
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income (loss) from discontinued operations, net of income tax									0	(86)	(101)
Brighthouse Financial, Inc | Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains (Losses) on Derivatives | Interest rate swaps
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income (loss) from discontinued operations, net of income tax									0	2	36
Brighthouse Financial, Inc | Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains (Losses) on Derivatives | Interest rate forwards
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income (loss) from discontinued operations, net of income tax									0	3	4
Brighthouse Financial, Inc | Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains (Losses) on Derivatives | Foreign currency swaps
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income (loss) from discontinued operations, net of income tax									$ 0	$ 11	$ 5