Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Assets
Amortized cost of fixed maturity securities available-for-sale	$ 310,004	$ 310,811
Debt Securities, Available-for-sale, Allowance for Credit Loss	68	81
Mortgage Loans, Allowance for Credit Loss	563	590
Residential mortgage loans — FVO	80,964	83,919
Real estate and real estate joint ventures (includes $225 and $169, respectively, under the fair value option and $0 and $128, respectively, of real estate held-for-sale)	12,182	11,933
Real Estate Held-for-sale	0	128
Other Invested Assets - Leveraged and Direct Financing Leases	2,019	2,156
Other invested assets relating to variable interest entities	18,683	20,593
Cash and cash equivalents relating to variable interest entities	18,956	19,795
Premiums, reinsurance and other receivables relating to variable interest entities	17,816	17,870
Other assets relating to variable interest entities	11,614	11,685
Liabilities
Long-term debt, at estimated fair value, relating to variable interest entities	14,010	14,603
Other liabilities relating to variable interest entities	$ 23,697	$ 23,614
MetLife, Inc.’s stockholders’ equity:
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, aggregate liquidation preference	$ 3,905	$ 4,405
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	3,000,000,000	3,000,000,000
Common stock, shares issued	1,186,092,767	1,181,614,288
Common stock, shares outstanding	844,531,818	892,910,600
Treasury stock, shares	341,560,949	288,703,688
Residential mortgage loans - FVO
Assets
Residential mortgage loans — FVO	$ 134	$ 165
Real estate and real estate joint venture [Member]
Assets
Real estate and real estate joint ventures (includes $225 and $169, respectively, under the fair value option and $0 and $128, respectively, of real estate held-for-sale)	225	169
Variable interest entities
Assets
Other invested assets relating to variable interest entities	356	332
Cash and cash equivalents relating to variable interest entities	13	12
Premiums, reinsurance and other receivables relating to variable interest entities	5	4
Other assets relating to variable interest entities	1	1
Liabilities
Long-term debt, at estimated fair value, relating to variable interest entities	0	5
Other liabilities relating to variable interest entities	$ 1	$ 1