Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Investments:
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $340,870 and $329,811, respectively; includes $3,378 and $3,225, respectively, relating to variable interest entities)	$ 374,266	$ 350,271
Equity securities available-for-sale, at estimated fair value (cost: $2,838 and $3,208, respectively)	2,891	3,023
Fair value option and trading securities, at estimated fair value (includes $659 and $473, respectively, of actively traded securities; and $112 and $280, respectively, relating to variable interest entities)	16,348	18,268
Mortgage loans:
Held-for-investment, principally at amortized cost (net of valuation allowances of $347 and $481, respectively; includes $2,715 and $3,187, respectively, at estimated fair value, relating to variable interest entities)	56,592	56,915
Held-for-sale, principally at estimated fair value (includes $49 and $10,716, respectively, under the fair value option)	414	15,178
Mortgage loans, net	57,006	72,093
Policy loans	11,884	11,892
Real estate and real estate joint ventures (includes $10 and $15, respectively, relating to variable interest entities)	9,918	8,563
Other limited partnership interests (includes $274 and $259, respectively, relating to variable interest entities)	6,688	6,378
Short-term investments, principally at estimated fair value	16,906	17,310
Other invested assets, principally at estimated fair value (includes $81 and $98, respectively, relating to variable interest entities)	21,145	23,581
Total investments	517,052	511,379
Cash and cash equivalents, principally at estimated fair value (includes $99 and $176, respectively, relating to variable interest entities)	15,738	10,461
Accrued investment income (includes $13 and $16, respectively, relating to variable interest entities)	4,374	4,344
Premiums, reinsurance and other receivables (includes $5 and $12, respectively, relating to variable interest entities)	21,634	22,481
Deferred policy acquisition costs and value of business acquired	24,761	24,619
Goodwill	9,953	11,935
Other assets (includes $5 and $5, respectively, relating to variable interest entities)	7,876	7,984
Separate account assets	235,393	203,023
Total assets	836,781	796,226
Liabilities
Future policy benefits	192,351	184,275
Policyholder account balances	225,821	217,700
Other policy-related balances	15,463	15,599
Policyholder dividends payable	728	774
Policyholder dividend obligation	3,828	2,919
Payables for collateral under securities loaned and other transactions	33,687	33,716
Bank deposits	6,416	10,507
Short-term debt	100	686
Long-term debt (includes $2,527 and $3,068, respectively, at estimated fair value, relating to variable interest entities)	19,062	23,692
Collateral financing arrangements	4,196	4,647
Junior subordinated debt securities	3,192	3,192
Current income tax payable	401	193
Deferred income tax liability	8,693	6,395
Other liabilities (includes $40 and $60, respectively, relating to variable interest entities; and $0 and $7,626, respectively, under the fair value option)	22,492	30,914
Separate account liabilities	235,393	203,023
Total liabilities	771,823	738,232
Contingencies, Commitments and Guarantees (Note 21)
Redeemable noncontrolling interests in partially owned consolidated subsidiaries	121	105
MetLife, Inc.'s stockholders' equity:
Preferred stock, par value $0.01 per share; 200,000,000 shares authorized: 84,000,000 shares issued and outstanding; $2,100 aggregate liquidation preference	1	1
Common stock, par value $0.01 per share; 3,000,000,000 shares authorized; 1,094,880,623 and 1,061,150,915 shares issued at December 31, 2012 and 2011, respectively; 1,091,686,736 and 1,057,957,028 shares outstanding at December 31, 2012 and 2011, respectively	11	11
Additional paid-in capital	28,011	26,782
Retained earnings	25,205	24,814
Treasury stock, at cost; 3,193,887 shares at December 31, 2012 and 2011	(172)	(172)
Accumulated other comprehensive income (loss)	11,397	6,083
Total MetLife, Inc.'s stockholders' equity	64,453	57,519
Noncontrolling interests	384	370
Total equity	64,837	57,889
Total liabilities and equity	$ 836,781	$ 796,226