Condensed Financial Information (Parent Company) (Condensed Statements of Operations) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Condensed Income Statements, Captions [Line Items]
Premiums	$ 687	$ 736	$ 847
Universal life and investment-type product policy fees	2,986	2,839	2,982
Net investment income	4,815	3,528	3,486
Other revenues	334	302	266
Net investment gains (losses)	(63)	279	92
Net derivative gains (losses)	(2,359)	(132)	(2,046)
Total revenues	6,400	7,552	5,627
Expenses
Net policyholder benefits and claims	3,213	5,689	3,538
Interest credited to policyholder account balances	1,286	1,061	1,031
Amortization of deferred policy acquisition costs and value of business acquired	105	696	395
Other expenses	1,800	1,844	1,809
Total expenses	6,404	9,290	6,773
Income (loss) before provision for income tax	(4)	(1,738)	(1,146)
Provision for income tax expense (benefit)	(71)	(433)	(338)
Net income (loss) attributable to Brighthouse Life Insurance Company	66	(1,306)	(809)
Comprehensive income (loss)	(1,454)	900	1,688
Parent Company
Condensed Income Statements, Captions [Line Items]
Premiums	461	428	452
Universal life and investment-type product policy fees	2,592	2,440	2,559
Net investment income	4,340	3,111	3,086
Other revenues	391	398	341
Net investment gains (losses)	12	296	88
Net derivative gains (losses)	(1,806)	(1,594)	(2,928)
Total revenues	5,990	5,079	3,598
Expenses
Net policyholder benefits and claims	2,131	3,087	2,623
Interest credited to policyholder account balances	1,122	912	869
Amortization of deferred policy acquisition costs and value of business acquired	66	626	337
Other expenses	2,733	2,102	1,920
Total expenses	6,052	6,727	5,749
Income (loss) before provision for income tax	(62)	(1,648)	(2,151)
Provision for income tax expense (benefit)	(78)	(410)	(534)
Income (loss) before equity in earnings (losses) of subsidiaries	16	(1,238)	(1,617)
Income (Loss) from Subsidiaries, Net of Tax	50	(68)	808
Net income (loss) attributable to Brighthouse Life Insurance Company	66	(1,306)	(809)
Comprehensive income (loss)	$ (1,454)	$ 900	$ 1,688