Separation (Separation Brighthouse - Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Aug. 04, 2017	Dec. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Common Stock, Shares, Issued	1,167,535,225		1,167,535,225			1,164,029,985
Common Stock, Shares Authorized	3,000,000,000		3,000,000,000			3,000,000,000
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax	$ (980)	$ 0	$ (1,171)	$ 0
Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation	(955)	0	(955)	0
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	(968)	(451)	(989)	(1,379)
Discontinued Operation, Separation Costs	25	0	216	0
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	501	1,159	2,482	5,522
Policyholder Benefits and Claims Incurred, Net	10,645	9,612	28,923	27,394
Operating Expenses	3,318	3,216	9,904	10,296
Income Tax Expense (Benefit)	(392)	135	(148)	1,253
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	(968)	(451)	(989)	(1,379)
Net investment gains (losses)	(606)	231	(439)	598
Impact of Separation [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax	(1,084)		(1,347)
Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation	42
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	(1,061)
Realized intercompany gains upon Separation	61
Discontinued Operation, Tax separation agreement Expense	1,093
Discontinued Operation, Tax Benefit from Provision for (Gain) Loss on Disposal	1,051
Discontinued Operation, Separation Costs	42
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	(104)		(176)
Realized Investment Gains (Losses)	(738)		(738)
Policyholder Benefits and Claims Incurred, Net	147		147
Operating Expenses	107		218
Income Tax Expense (Benefit)	(888)		(927)
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	(980)		(1,171)
Brighthouse Financial, Inc
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Common Stock, Shares, Issued					96,776,670
Common Stock, Shares Authorized					119,773,106
BHF Common Stock					80.80%
Discontinued Operation, Separation Costs	64	$ 51	470	$ 108
Net investment gains (losses)	(1,016)
Discontinued Operation, Other fees and costs required	$ 39		$ 333
Common Stock, Shares, Owned by MetLife, INC.	22,996,436		22,996,436
Discontinued Operation, Equity Method Investment Retained after Disposal, Ownership Interest after Disposal			19.20%
Equity Method Investment, Quoted Market Value	$ 1,400		$ 1,400
Gain (loss) in equity investment value	$ (45)