Consolidated Statements of Equity (Unaudited) - USD ($) $ in Millions	Total	Preferred Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	Treasury Stock at Cost	Accumulated Other Comprehensive Income (Loss)	Total MetLife, Inc.'s Stockholders' Equity	Noncontrolling Interests
Beginning Balance (Scenario, Previously Reported) at Dec. 31, 2016	$ 67,480	$ 0	$ 12	$ 30,944	$ 34,480	$ (3,474)	$ 5,347	$ 67,309	$ 171
Beginning Balance (Restatement Adjustment)	222	0	0	0	203	0	19	222	0
Beginning Balance at Dec. 31, 2016	67,702	0	12	30,944	34,683	(3,474)	5,366	67,531	171
Treasury stock acquired in connection with share repurchases	(858)					(858)		(858)
Stock-based compensation	46			46				46
Dividends on preferred stock	(6)				(6)			(6)
Dividends on common stock	(437)				(437)			(437)
Change in equity of noncontrolling interests	4							0	4
Net income (loss)	876				873			873	3
Other comprehensive income (loss), net of income tax | Scenario, Previously Reported							1,049
Other comprehensive income (loss), net of income tax | Restatement Adjustment							(19)
Other comprehensive income (loss), net of income tax	1,031						1,030	1,030	1
Ending Balance (Scenario, Previously Reported) at Mar. 31, 2017	68,108
Ending Balance (Restatement Adjustment)	250
Ending Balance at Mar. 31, 2017	68,358	0	12	30,990	35,113	(4,332)	6,396	68,179	179
Cumulative effects of changes in accounting principles, net of income tax (Note 1)	7	0	0	0	(905)	0	912	7	0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Adjusted Balance	58,877	0	12	31,111	25,622	(6,401)	8,339	58,683	194
Beginning Balance at Dec. 31, 2017	58,870	0	12	31,111	26,527	(6,401)	7,427	58,676	194
Preferred stock issuance	494	0		494				494
Treasury stock acquired in connection with share repurchases	(1,041)					(1,041)		(1,041)
Stock-based compensation	48			48				48
Dividends on preferred stock	(6)				(6)			(6)
Dividends on common stock	(416)				(416)			(416)
Change in equity of noncontrolling interests	0							0	0
Net income (loss)	1,257				1,253			1,253	4
Other comprehensive income (loss), net of income tax	(2,705)						(2,705)	(2,705)	0
Ending Balance at Mar. 31, 2018	$ 56,508	$ 0	$ 12	$ 31,653	$ 26,453	$ (7,442)	$ 5,634	$ 56,310	$ 198