Common stock, shares outstanding Common stock, shares issued Common stock, shares authorized Common stock, par value Preferred stock, aggregate liquidation preference Preferred stock, shares outstanding Preferred stock, shares authorized Preferred stock, par value Total liabilities and stockholders' equity Accumulated other comprehensive loss Treasury Stock, Value Treasury stock, at cost; 3,193,887 and 3,526,008 shares at March 31, 2010 and December 31, 2009, respectively Treasury Stock, Value, Ending Balance Treasury Stock, Value, Beginning Balance Treasury stock, at cost; 79,454,413 shares and 57,543,224 shares at September 30, 2008 and December 31, 2007, respectively Treasury stock, at cost; 3,193,887 and 3,526,008 shares at March 31, 2010 and December 31, 2009, respectively Retained earnings Additional paid-in capital Common Stock, Value, Issued Common Stock, Value, Issued, Ending Balance CommCommon stock, par value $0.01 per share; 3,000,000,000 shares authorized; xxx shares and 798,016,664 shares issued at September 30, 2009 and December 31, 2008, respectively; xxx shares and 793,629,070 shares outstanding at September 30, 2009 and December 31, 2008, respectivelyon Stock, Value, Issued, Beginning Balance Common Stock, Value, Issued, Total Common stock, par value $0.01 per share; 3,000,000,000 shares authorized; 822,586,896 and 822,359,818 shares issued at March 31, 2010 and December 31, 2009, respectively; 819,393,009 and 818,833,810 shares outstanding at March 31, 2010 and December 31, 2009, respectively 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 Total liabilities Separate account liabilities Other liabilities (includes $96 and $26, respectively, relating to variable interest entities) Other Liabilities Other liabilities relating to variable interest entities Other Liabilities, Total Long-term Debt Long-term debt relating to variable interest entities Long-term debt Long-term debt (includes $7,164 and $64, respectively, relating to variable interest entities) Short-term debt Policyholder dividends payable Other policyholder funds Future policy benefits Total assets Separate account assets Deferred income tax assets Premiums and Other Receivables, Net Premiums and Other Receivables, Net Premiums and other receivables Premiums, reinsurance and other receivables Accrued investment income (includes $39 and $0, respectively, relating to variable interest entities) Accrued Investment Income Receivable Accrued investment income relating to variable interest entities Accrued Investment Income Receivable, Total Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents, from continuing operations, end of period Cash and cash equivalents, from continuing operations, beginning of period Cash and cash equivalents relating to variable interest entities Cash and cash equivalents, from continuing operations, end of period Cash and cash equivalents (includes $267 and $68, respectively, relating to variable interest entities) Total investments Short-term investments Other limited partnership interests (includes $226 and $236, respectively, relating to variable interest entities) Other limited partnership interests Other limited partnership interests relating to variable interest entities Other limited partnership interests. Available-for-sale Securities, Equity Securities Equity securities available-for-sale, at estimated fair value (cost: $3,106 and $3,187, respectively) Policy loans Net income (loss) available to MetLife, Inc.'s common shareholders per common share: Net income available to common shareholders per common share Net income available to common shareholders per common share. Income (loss) from continuing operations, net of income tax, available to MetLife, Inc.'s common shareholders per common share: Income from continuing operations available to common shareholders per common share Income from continuing operations available to common shareholders per common share. Diluted Basic Diluted Net income (loss) available to MetLife, Inc.'s common shareholders Less: Preferred stock dividends Net income (loss) attributable to MetLife, Inc. Net income (loss) attributable to MetLife, Inc. Income (loss) from discontinued operations, net of income tax Provision for income tax expense (benefit) Revenues Expenses Policyholder dividends Interest credited to policyholder account balances Policyholder benefits and claims Total revenues Gain (Loss) on Investments Total net investment gains (losses) Gain (Loss) on Investments Total net investment gains (losses) Net investment gains (losses) Other revenues Net investment income Premiums Change in cash and cash equivalents Net cash provided by (used in) financing activities Other, net Dividends on preferred stock Repayments of Long-term Debt Long-term debt repaid Repayments of Long-term Debt Long-term debt repaid Long-term debt repaid (includes ($202) and $0, respectively, related to consolidated securitization entities) Long-term debt issued Net change in short-term debt Withdrawals Policyholder account balances: Deposits Cash flows from financing activities Net cash used in investing activities Other, net Net change in policy loans Net change in short-term investments Business, Basis of Presentation, and Summary of Significant Accounting Policies [Abstract] Business, Basis of Presentation and Summary of Significant Accounting Policies [Abstract] Business, Basis of Presentation, and Summary of Significant Accounting Policies. Long-term and Short-term Debt [Abstract] Long-term and Short-term Debt [Abstract] Long-term and Short-term Debt. Contingencies, Commitments and Guarantees [Abstract] Contingencies, Commitments and Guarantees [Abstract] Contingencies, Commitments and Guarantees. Business Segment Information [Abstract] Business Segment Information [Abstract] Business Segment Information. Discontinued Operations [Abstract] Discontinued Operations [Abstract] Discontinued Operations. Fair Value [Abstract] Fair Value [Abstract] Fair Value. Defined benefit plans adjustment, net of income tax Foreign currency translation adjustments, net of income tax Other comprehensive income (loss): Stock-based compensation Other comprehensive income (loss) Sales, maturities and repayments of equity securities Sales, maturities and repayments of equity securities The cash inflow associated with the sale, maturity and repayment of equity securities classified as available-for-sale securities. Sales, maturities and repayments of fixed maturity securities Sales Maturites And Repayments Of Fixed Maturity Securities The cash inflow associated with the sale, maturity and repayments of debt securities classified as available-for-sale securities. Business Basis Of Presentation And Summary Of Significant Accounting Policies [Text Block] Business Basis of Presentation and Summary of Significant Accounting Policies Business, Basis of Presentation, and Summary of Significant Accounting Policies Business, Basis of Presentation and Summary of Significant Accounting Policies Business, Basis of Presentation, and Summary of Significant Accounting Policies. Investments Derivative Financial Instruments Long-term and Short-term Debt Contingencies Commitments and Guarantees [Text Block] Contingencies, Commitments and Guarantees Describes and quantifies the loss contingencies that were reported in the period or disclosed as of the balance sheet date as well as give a description of significant arrangements with third parties, which includes operating lease arrangements and arrangements in which the entity has agreed to expend funds to procure goods or services Also provides pertinent information about each guarantee obligation, or each group of similar guarantee obligations, including (a) the nature of the guarantee, including its term, how it arose, and the events or circumstances that would require the guarantor to perform under the guarantee; (b) the maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee; (c) the current carrying amount of the liability, if any, for the guarantor's obligations under the guarantee; and (d) the nature of any recourse provisions under the guarantee, and any assets held either as collateral or by third parties, and any relevant related party disclosure. Excludes disclosures about product warranties. Business Segment Information Discontinued Operations Fair Value Short-term investments Short-term Investments Short-term debt Short-term Borrowings Additional paid-in capital Additional Paid in Capital, Beginning Balance Additional Paid in Capital, Ending Balance Additional Paid in Capital Retained earnings Retained Earnings (Accumulated Deficit), Beginning Balance Retained Earnings (Accumulated Deficit), Ending Balance Retained Earnings (Accumulated Deficit) Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning Balance Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance Accumulated Other Comprehensive Income (Loss), Net of Tax Assets Liabilities and Stockholders' Equity Treasury stock, shares Preferred stock, shares issued Cost of trading securities Cost of Trading Securities. Cost of trading securities Deferred policy acquisition costs and value of business acquired Deferred policy acquisition costs and value of business acquired Deferred Policy Acquisition Costs and Value of Business Acquired Junior subordinated debt securities Junior Subordinated Notes Collateral financig arrangements relating to variable interest entities Junior Subordinated Notes, Total Mortgage loans: Mortgage and Consumer loans Abstract Mortgage and Consumer loans. Total equity Cash flows from investing activities Net income Premiums Premiums Earned, Net Net investment income Policyholder benefits and claims Policyholder Benefits and Claims Incurred, Net Provision for income tax expense (benefit) Income Tax Expense (Benefit) Income (loss) from discontinued operations, net of income tax Income (Loss) from Discontinued Operations, Net of Tax Basic Earnings Per Share, Basic Diluted Earnings Per Share, Diluted Debt issuance costs Effect of change in foreign currency exchange rates on cash balances Cash and cash equivalents, subsidiaries held-for-sale, end of period Cash and cash equivalents, subsidiaries held-for-sale, end of period Cash and cash equivalents subsidiaries held for sale end of period Cash and cash equivalents, subsidiaries held-for-sale, end of period. Net change in short-term investments Payments for (Proceeds from) Short-term Investments Net change in short-term debt Proceeds from (Repayments of) Short-term Debt Long-term debt issued Proceeds from Issuance of Long-term Debt Effect of change in foreign currency exchange rates on cash balances Effect of Exchange Rate on Cash and Cash Equivalents Supplemental disclosures of cash flow information: Non-cash transactions during the period: Net cash paid (received) during the period for interest Interest Net cash paid (received) during the period for income tax Income tax Remarketing of debt securities: Remarketing of debt securities Abstract Remarketing of debt securities. Fixed maturity securities redeemed Fixed maturity securities redeemed Fixed maturity securities redeemed. Junior subordinated debt securities redeemed Supplemental Junior subordinated debt securities redeemed Junior subordinated debt securities redeemed. Real estate and real estate joint ventures acquired in satisfaction of debt Supplemental Real estate acquired in satisfaction of debt Real estate acquired in satisfaction of debt. Cash and cash equivalents, end of period Cash and cash equivalents, end of period Cash and cash equivalents, end of period Cash and cash equivalents, end of period. Beginning Balance Ending Balance Common stock issuance - newly issued shares Treasury stock transactions, net Treasury stock transactions net Treasury stock transactions, net. Change in equity of noncontrolling interests Change in equity of noncontrolling interests Change in equity of noncontrolling interests. Comprehensive income (loss): Foreign currency translation adjustments, net of income tax Other Comprehensive Income, Foreign Currency Transaction and Translation Adjustment, Net of Tax, Period Increase (Decrease) Defined benefit plans adjustment, net of income tax Other Comprehensive Income, Defined Benefit Plans Adjustment, Net of Tax, Period Increase (Decrease) Other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax, Period Increase (Decrease) Preferred Stock Common Stock Additional Paid-in Capital Retained Earnings Treasury Stock at Cost Accumulated Other Comprehensive Income (Loss) Net Unrealized Investment Gains (Losses) Accumulated Other Comprehensive Income (Loss) Foreign Currency Translation Adjustments Accumulated Other Comprehensive Income (Loss) Defined Benefit Plans Adjustment Accumulated Other Comprehensive Income (Loss) Cumulative effect of changes in accounting principles, net of income tax Other Assets Other assets relating to variable interest entities Other Assets, Total Other assets (includes $10 and $16, respectively, relating to variable interest entities) Cash disposed from sales of businesses Proceeds from Divestiture of Businesses Net Cash Provided by (Used in) Operating Activities Net cash provided by (used in) operating activities Net cash provided by operating activities Net Cash Provided by (Used in) Financing Activities Net Income (Loss) Cash and cash equivalents, subsidiaries held-for-sale, beginning of period Cash and cash equivalents, subsidiaries held-for-sale, beginning of period Cash and cash equivalent subsidiaries held for sale beginning of period Cash and cash equivalents, subsidiaries held-for-sale, beginning of period. Cash and cash equivalents, beginning of period Cash and cash equivalents, beginning of period Cash and cash equivalents beginning period Cash and cash equivalents, beginning of period. Proceeds from Divestiture of Businesses Total investments Investments Separate account assets Separate Account Assets Separate account liabilities Separate Accounts, Liability Accumulated Other Comprehensive Income (Loss), Net of Tax Income Tax Expense (Benefit) Income (Loss) from Discontinued Operations, Net of Tax Less: Preferred stock dividends Preferred Stock Dividends Diluted Income (Loss) from Continuing Operations, Per Diluted Share Earnings Per Share, Basic Other Comprehensive Income (Loss), Net of Tax Stockholders' Equity Other, net Payments for (Proceeds from) Other Investing Activities Other, net Proceeds from (Payments for) Other Financing Activities Effect of Exchange Rate on Cash and Cash Equivalents Change in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents, beginning of year Cash and cash equivalents, end of year Cash and cash equivalents, subsidiaries held-for-sale, beginning of year Cash and cash equivalents, subsidiaries held-for-sale, end of year Interest Paid Income Taxes Paid Fixed maturity securities redeemed Junior subordinated debt securities redeemed Real estate and real estate joint ventures acquired in satisfaction of debt Short-term Investments Additional Paid in Capital Preferred Stock, Liquidation Preference Cumulative effect of changes in accounting principles, net of income tax (Note 1) Cumulative Effect of Initial Adoption of New Accounting Principle Available-for-sale Securities, Debt Securities Fixed maturity securities relating to variable interest entities Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $238,061 and $229,709, respectively; includes $3,144 and $3,171, respectively, relating to variable interest entities) Other Comprehensive Income, Foreign Currency Transaction and Translation Adjustment, Net of Tax Other Comprehensive Income, Defined Benefit Plans Adjustment, Net of Tax Other expenses Operating Expenses Held-for-sale, principally at estimated fair value Loans Held-for-sale, Mortgages Payables for collateral under securities loaned and other transactions Deposits Received for Securities Loaned, at Carrying Value Proceeds from Annuities and Investment Certificates Repayments of Annuities and Investment Certificates Cost of equity securities available-for-sale Equity securities available for sale at cost Equity securities available-for-sale, at cost. Long-term and Short-term Debt [Abstract] Goodwill Goodwill, Beginning Balance Goodwill, Ending Balance Goodwill Total MetLife, Inc.'s stockholders' equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Ending Balance Beginning Balance Total equity Net income (loss) Net income (loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Less: Net income (loss) attributable to noncontrolling interests Net Income (Loss) Attributable to Noncontrolling Interest Income (loss) from continuing operations, net of income tax Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest, Total Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest Earnings Per Common Share Earnings Per Share [Text Block] Dividends on preferred stock Dividends, Preferred Stock, Cash Noncontrolling Interests Noncontrolling Interests Entity Registrant Name Entity Central Index Key Document Type Document Period End Date Amendment Flag Current Fiscal Year End Date Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Current Reporting Status Entity Filer Category Entity Public Float Entity Common Stock, Shares Outstanding Statement [Table] Statement [Line Items] Assets [Abstract] Loans, Gross, Insurance Policy Deferred Policy Acquisition Costs and Value of Business Acquired Deferred Tax Assets, Net Assets Liabilities and Stockholders' Equity [Abstract] Liability for Future Policy Benefits Other Policyholder Funds Policyholder Dividends Payable Short-term Borrowings Liabilities Commitments and Contingencies Contingencies, Commitments and Guarantees (Note 8) Preferred Stock, Value, Issued Retained Earnings (Accumulated Deficit) Liabilities and Stockholders' Equity Preferred Stock, Par or Stated Value Per Share Preferred Stock, Shares Authorized Preferred Stock, Shares Issued Preferred Stock, Shares Outstanding Common Stock, Par or Stated Value Per Share Common Stock, Shares Authorized Common Stock, Shares, Issued Common Stock, Shares, Outstanding Treasury Stock, Shares Revenues [Abstract] Premiums Earned, Net Net Investment Income Other Income Revenues Benefits, Losses and Expenses [Abstract] Policyholder Benefits and Claims Incurred, Net Interest Credited to Policyholders Account Balances Policyholder Dividends Net Income (Loss) Available to Common Stockholders, Basic Earnings Per Share, Diluted Stock Issued During Period, Value, New Issues Stock Issued During Period, Value, Share-based Compensation Comprehensive Income, Net of Tax, Attributable to Parent [Abstract] Other Comprehensive Income (Loss), Net of Tax [Abstract] Statement, Equity Components [Axis] Equity Component [Domain] Total MetLife, Inc.'s Stockholders' Equity Net Cash Provided by (Used in) Investing Activities [Abstract] Payments for (Proceeds from) Short-term Investments Payments to Fund Policy Loans Net Cash Provided by (Used in) Investing Activities Net Cash Provided by (Used in) Financing Activities [Abstract] Proceeds from (Repayments of) Short-term Debt Proceeds from Issuance of Long-term Debt Payments of Debt Issuance Costs Payments of Dividends, Preferred Stock and Preference Stock Net Cash Provided by (Used in) Financing Activities Supplemental Cash Flow Information [Abstract] Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Derivative Instruments and Hedging Activities Disclosure [Text Block] Debt Disclosure [Text Block] Segment Reporting Disclosure [Text Block] Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Fair Value Disclosures [Text Block] Comprehensive income (loss) Comprehensive Income, Net of Tax, Including Portion Attributable to Noncontrolling Interest Investments: Investments [Abstract] Net investment gains (losses): Gain (Loss) on Investments [Abstract] Current income tax recoverable Income Taxes Receivable Total MetLife, Inc.s Stockholders' Equity Gain (Loss) on Sale of Other Investments Other net investment gains (losses), net Other net investment gains (losses), net Other-than-temporary impairments on fixed maturity securities transferred to other comprehensive loss Other than temporary impairments on fixed maturity securities transferred to other comprehensive loss Other-than-temporary impairments on fixed maturity securities transferred to other comprehensive loss. Other, net Net change in policy loans Net change in short-term investments Dividends on preferred stock Debt issuance costs Policyholder account balances: Withdrawals Interim Condensed Consolidated Balance Sheets [Abstract] Balance Sheets [Abstract] Interim Condensed Consolidated Statements of Operations [Abstract] Statements of Income [Abstract] Interim Condensed Consolidated Statements of Stockholders' Equity [Abstract] Statement Of Stockholder Equity [Abstract] Interim Condensed Consolidated Statements of Cash Flows [Abstract] Statements of Cash Flows [Abstract] Derivative Financial Instruments [Abstract] Derivative Financial Instruments [Abstract] Earnings Per Common Share [Abstract] Earnings Per Common Share [Abstract] Preferred Stock, Value, Issued, Total Preferred Stock, Value, Issued, Beginning Balance 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 Accumulated Other Comprehensive Loss Other Than Temporary Impairments Member Accumulated Other Comprehensive Loss Other Than Temporary Impairments Accumulated Other Comprehensive Loss Other Than Temporary Impairments Accumulated Other Comprehensive Loss Other Than Temporary Impairments Long-term and Short-term Debt [Abstract] Trading Securities Trading securities relating to variable interest entities Trading Securities, Total Trading securities, at estimated fair value (cost: $2,978 and $2,249, respectively; includes $274 and $0, respectively, relating to variable interest entities) Noncontrolling interests Stockholders' Equity Attributable to Noncontrolling Interest, Beginning Balance Stockholders' Equity Attributable to Noncontrolling Interest, Ending Balance Stockholders' Equity Attributable to Noncontrolling Interest Net income (loss) Liabilities Liabilities [Abstract] Closed Block [Text Block] Closed Block Closed Block. Employee Benefit Plans [Abstract] Employee Benefit Plans Schedule of Defined Benefit Plans Disclosures [Text Block] Equity Stockholders' Equity Note Disclosure [Text Block] Subsequent Events [Abstract] Subsequent Events. Subsequent Events Schedule of Subsequent Events [Text Block] Equity [Abstract] Bank deposits Deposits, Total Deposits Net change in bank deposits Increase (Decrease) in Deposits, Total Increase (Decrease) in Deposits Common stock issued to settle stock forward contracts Common stock issued to settle stock forward contracts Common stock issued to settle stock forward contracts. Common stock issued to settle stock forward contracts Mortgage loans, net Mortgage Loans on Real Estate, Beginning Balance Mortgage Loans on Real Estate, Ending Balance Mortgage Loans on Real Estate Net change in other invested assets Net change in other invested assets The net cash outflow (inflow) from other investing activities including derivative instruments, leverged leases and other invested assets. Net change in other invested assets Mortgage loans: Mortgage loans [Abstract] Mortgage loans. Mortgage Loans on Real Estate, Commercial and Consumer, Net Mortgage loans relating to variable interest entities Mortgage Loans on Real Estate, Commercial and Consumer, Net, Total Held-for-investment, at amortized cost (net of valuation allowances of $751 and $721, respectively; includes $7,065 and $0, respectively, relating to variable interest entities) Real estate held-for-sale Real Estate Held-for-sale Other invested assets (includes $110 and $137, respectively, relating to variable interest entities) Other Investments Other invested assets relating to variable interest entities Policyholder account balances Policyholder Contract Deposits Amortized cost of fixed maturity securities available-for-sale Available-for-sale Securities, Debt Maturities, Amortized Cost, Total Available-for-sale Securities, Debt Maturities, Amortized Cost Valuation allowances for held-for-investment Allowance for Loan and Lease Losses, Real Estate Collateral financing arrangements Secured Debt, Total Secured Debt Other-than-temporary impairments on fixed maturity securities Other-than-temporary impairments on fixed maturity securities This element represents the amount of loss recognized for other than temporary impairments of investments in debt securities Other-than-temporary impairments on fixed maturity securities Universal life and investment-type product policy fees Insurance Commissions and Fees Total expenses Benefits, Losses and Expenses Income (loss) from continuing operations before provision for income tax Income (loss) from continuing operations before provision for income tax Sum of operating profit and nonoperating income (expense) before income (loss) from equity method investments, income taxes, extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest. Basic Income (Loss) from Continuing Operations, Per Basic Share Real Estate Investments, Unconsolidated Real Estate and Other Joint Ventures Real estate and real estate joint ventures held-for-investment relating to variable interest entities Real estate and real estate joint ventures held-for-investment (includes $19 and $18, respectively, relating to variable interest entities) Current income tax payable Accrued Income Taxes, Current Purchases of fixed maturity securities Payments to Acquire Available-for-sale Securities, Debt Purchases of fixed maturity securities Purchases of equity securities Purchases of equity securities Payments to Acquire Available-for-sale Securities, Equity Purchases of real estate and real estate joint ventures Payments To Acquire Real Estate And Real Estate Joint Ventures The cash outflow associated with the purchase of real estate held for investment and real estate joint ventures. Purchases of real estate and real estate joint ventures Purchases of other limited partnership interests Payments To Acquire Other Limited Partneship Interests Cash outflow from limited partnership investments held by the entity for investment purposes. Purchases of other limited partnership interests Sales, maturities and repayments of real estate and real estate joint ventures Proceeds To Acquire Real Estate And Real Estate Joint Ventures Cash received from the sale of real estate that is held for investment and cash received for real estate joint ventures, that is part of an investing activity during the period. Sales, maturities and repayments of other limited partnership interests Proceeds From Sale Of Other Limited Partneship Interests Cash inflow from limited partnership investments held by the entity for investment purposes. Sales of businesses, net of cash disposed of $0 and $180, respectively Proceeds from Divestiture of Businesses, Net of Cash Divested, Total Proceeds from Divestiture of Businesses, Net of Cash Divested Unrealized gains (losses) on derivative instruments, net of income tax Other Comprehensive Income, Derivatives Qualifying as Hedges, Net of Tax, Total Other Comprehensive Income, Derivatives Qualifying as Hedges, Net of Tax Unrealized investment gains (losses), net of related offsets and income tax Other Comprehensive Income, Available-for-sale Securities Adjustment, Net of Tax, Total Other Comprehensive Income, Available-for-sale Securities Adjustment, Net of Tax Purchases of Mortgage loans Payments to Acquire Mortgage Notes Receivable Purchases of mortgage loans Proceeds from Sale and Collection of Mortgage Notes Receivable Sales, maturities and repayments of mortgage loans Collateral financing arrangements issued Proceeds from Issuance of Secured Debt Net change in payables for collateral under securities loaned and other transactions Net change in payables for collateral under securities loaned and other transactions Net change in payables for collateral under securities loaned and other transactions. Other Expense Schedule of Other Operating Cost and Expense, by Component [Text Block] Other Expense [Abstract] Other Expenses [Abstract] Closed Block [Abstract] Long-term debt issued Supplemental Long Term Debt Issued Supplemental long term debt issued. Long-term debt issued MetLife, Inc.'s stockholders' equity: Stockholders' Equity Attributable to Parent [Abstract] Document Fiscal Year Focus Document Fiscal Period Focus Document and Entity Information [Abstract] Document and Entity Information. Stockholders' Equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Previously Reported Statement, Scenario [Axis] Scenario, Unspecified [Domain] Adjustment To Additional Paid In Capital Deferral Of Stock Based Compensation Deferral of stock-based compensation Adjustment to additional paid in capital deferral of stock based compensation. Cash received in connection with freestanding derivatives. Cash received in connection with freestanding derivatives Cash received in connection with freestanding derivatives Cash paid in connection with freestanding derivatives Cash paid in connection with freestanding derivatives Cash paid in connection with freestanding derivatives Cash paid in connection with freestanding derivatives. Pending Acquisition. Pending Acquisition [Abstract] Business Combination Disclosure [Text Block] Pending Acquisition Variable interest entities Variable Interest by Interest Type [Axis] Variable Interest Type [Domain]