Business, Basis of Presentation and Summary of Significant Accounting Policies	3 Months Ended
Mar. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business, Basis of Presentation and Summary of Significant Accounting Policies	1. Business, Basis of Presentation and Summary of Significant Accounting Policies Business “MetLife USA” and the “Company” refer to MetLife Insurance Company USA (formerly, MetLife Insurance Company of Connecticut (“MICC”)), a Delaware corporation originally incorporated in Connecticut in 1863, and its subsidiaries. MetLife Insurance Company USA is a wholly-owned subsidiary of MetLife, Inc. (MetLife, Inc., together with its subsidiaries and affiliates, “MetLife”). The Company offers individual annuities, individual life insurance, and institutional protection and asset accumulation products. In November 2014, MetLife Insurance Company of Connecticut re-domesticated from Connecticut to Delaware, changed its name to MetLife Insurance Company USA and merged with its subsidiary, MetLife Investors USA Insurance Company (“MLI-USA”), and its affiliate, MetLife Investors Insurance Company, each a U.S. insurance company that issued variable annuity products in addition to other products, and Exeter Reassurance Company, Ltd., a former offshore, reinsurance subsidiary of MetLife, Inc. and affiliate of MICC that mainly reinsured guarantees associated with variable annuity products (the “Mergers”). The surviving entity of the Mergers was MetLife USA. The Mergers represent a transaction among entities under common control and have been accounted for in a manner similar to the pooling-of-interests method, which requires that the merged entities be combined at their historical cost. The Company’s consolidated financial statements and related footnotes are presented as if the transaction occurred at the beginning of the earliest date presented and the prior periods have been retrospectively adjusted. See Note 3 of the Notes to the Consolidated Financial Statements included in MetLife Insurance Company USA’s Annual Report on Form 10‑K for the year ended December 31, 2014 (the “2014 Annual Report”) for further information on the Mergers. The Company is organized into two segments: Retail and Corporate Benefit Funding. Basis of Presentation The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to adopt accounting policies and make estimates and assumptions that affect amounts reported in the interim condensed consolidated financial statements. In applying these policies and estimates, management makes subjective and complex judgments that frequently require assumptions about matters that are inherently uncertain. Many of these policies, estimates and related judgments are common in the insurance and financial services industries; others are specific to the Company’s business and operations. Actual results could differ from estimates. The accompanying interim condensed consolidated financial statements include the accounts of MetLife USA, as well as partnerships and joint ventures in which the Company has control, and variable interest entities (“VIEs”) for which the Company is the primary beneficiary. Intercompany accounts and transactions have been eliminated. The Company uses the equity method of accounting for equity securities when it has significant influence or at least 20% interest and for real estate joint ventures and other limited partnership interests (“investees”) when it has more than a minor ownership interest or more than a minor influence over the investee’s operations, but does not have a controlling financial interest. The Company generally recognizes its share of the investee’s earnings on a three-month lag in instances where the investee’s financial information is not sufficiently timely or when the investee’s reporting period differs from the Company’s reporting period. The Company uses the cost method of accounting for investments in which it has virtually no influence over the investee’s operations. Certain amounts in the prior year periods’ interim condensed consolidated financial statements and related footnotes thereto have been reclassified to conform with the 2015 presentation as discussed throughout the Notes to the Interim Condensed Consolidated Financial Statements. Since the Company is a member of a controlled group of affiliated companies, its results may not be indicative of those of a stand-alone entity. The accompanying interim condensed consolidated financial statements are unaudited and reflect all adjustments (including normal recurring adjustments) necessary to present fairly the financial position, results of operations and cash flows for the interim periods presented in conformity with GAAP. Interim results are not necessarily indicative of full year performance. The December 31, 2014 consolidated balance sheet data was derived from audited consolidated financial statements included in the 2014 Annual Report, which include all disclosures required by GAAP. Therefore, these interim condensed consolidated financial statements should be read in conjunction with the consolidated financial statements of the Company included in the 2014 Annual Report. Adoption of New Accounting Pronouncements Effective January 1, 2015, the Company adopted guidance requiring repurchase-to-maturity transactions and repurchase financing arrangements to be accounted for as secured borrowings and providing for enhanced disclosures, including the nature of collateral pledged and the time to maturity. Certain interim period disclosures for repurchase agreements and securities lending transactions are not required until the second quarter of 2015. The adoption of this new guidance did not have a material impact on the Company’s consolidated financial statements. Future Adoption of New Accounting Pronouncements In May, 2015, the Financial Accounting Standards Board (“FASB”) issued new guidance on fair value measurement (Accounting Standards Update (“ASU”) 2015-07, Fair Value Measurement (Topic 820): Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent)), effective for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years and which should be applied retrospectively to all periods presented. Earlier application is permitted. The new amendments in this ASU remove the requirement to categorize within the fair value hierarchy all investments for which fair value is measured using the net asset value (“NAV”) per share practical expedient. In addition, the amendments remove the requirement to make certain disclosures for all investments that are eligible to be measured at fair value using the net asset value per share practical expedient. The Company is currently evaluating the impact of this guidance on its consolidated financial statements. In April 2015, the FASB issued new guidance on accounting for fees paid in a cloud computing arrangement (ASU 2015-05, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement), effective for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. Early adoption of the new guidance is permitted and an entity can elect to adopt the guidance either: (1) prospectively to all arrangements entered into or materially modified after the effective date; or (2) retrospectively. The new guidance provides that all software licenses included in cloud computing arrangements be accounted for consistent with other licenses of intangible assets. However, if a cloud computing arrangement does not include a software license, the arrangement should be accounted for as a service contract, the accounting for which did not change. The Company is currently evaluating the impact of this guidance on its consolidated financial statements. In April 2015, the FASB issued new guidance on the presentation of debt issuance costs (ASU 2015-03, Interest - Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs), effective for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years and should be applied retrospectively to all periods presented. Early adoption of the new guidance is permitted for financial statements that have not been previously issued. The new guidance will require that debt issuance costs be presented in the balance sheet as a direct deduction from the related debt liability rather than as an asset, consistent with debt discounts. However, the current recognition and measurement guidance for debt issuance costs are not affected by the new guidance. The Company is currently evaluating the impact of this guidance on its consolidated financial statements. In February 2015, the FASB issued new guidance to improve consolidation guidance for legal entities (ASU 2015-02, Consolidation (Topic 810): Amendments to the Consolidation Analysis), effective for fiscal years beginning after December 15, 2015 and interim periods within those years and early adoption is permitted. The new standard is intended to improve targeted areas of the consolidation guidance for legal entities such as limited partnerships, limited liability corporations, and securitization structures. The amendments in this ASU affect the consolidation evaluation for reporting organizations. In addition, the amendments in this ASU simplify and improve current GAAP by reducing the number of consolidation models. The Company is currently evaluating the impact of this guidance on its consolidated financial statements. In May 2014, the FASB issued a comprehensive new revenue recognition standard (ASU 2014‑09, Revenue from Contracts with Customers (Topic 606)), effective retrospectively for fiscal years beginning after December 15, 2016 and interim periods within those years. Early adoption of this standard is not permitted. The new guidance will supersede nearly all existing revenue recognition guidance under GAAP; however, it will not impact the accounting for insurance contracts, leases, financial instruments and guarantees. For those contracts that are impacted by the new guidance, the guidance will require an entity to recognize revenue upon the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The Company is currently evaluating the impact of this guidance on its consolidated financial statements.

Business

“MetLife USA” and the “Company” refer to MetLife Insurance Company USA (formerly, MetLife Insurance Company of Connecticut (“MICC”)), a Delaware corporation originally incorporated in Connecticut in 1863, and its subsidiaries. MetLife Insurance Company USA is a wholly-owned subsidiary of MetLife, Inc. (MetLife, Inc., together with its subsidiaries and affiliates, “MetLife”). The Company offers individual annuities, individual life insurance, and institutional protection and asset accumulation products.

In November 2014, MetLife Insurance Company of Connecticut re-domesticated from Connecticut to Delaware, changed its name to MetLife Insurance Company USA and merged with its subsidiary, MetLife Investors USA Insurance Company (“MLI-USA”), and its affiliate, MetLife Investors Insurance Company, each a U.S. insurance company that issued variable annuity products in addition to other products, and Exeter Reassurance Company, Ltd., a former offshore, reinsurance subsidiary of MetLife, Inc. and affiliate of MICC that mainly reinsured guarantees associated with variable annuity products (the “Mergers”). The surviving entity of the Mergers was MetLife USA. The Mergers represent a transaction among entities under common control and have been accounted for in a manner similar to the pooling-of-interests method, which requires that the merged entities be combined at their historical cost. The Company’s consolidated financial statements and related footnotes are presented as if the transaction occurred at the beginning of the earliest date presented and the prior periods have been retrospectively adjusted. See Note 3 of the Notes to the Consolidated Financial Statements included in MetLife Insurance Company USA’s Annual Report on Form 10‑K for the year ended December 31, 2014 (the “2014 Annual Report”) for further information on the Mergers.

The Company is organized into two segments: Retail and Corporate Benefit Funding.

Basis of Presentation

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to adopt accounting policies and make estimates and assumptions that affect amounts reported in the interim condensed consolidated financial statements. In applying these policies and estimates, management makes subjective and complex judgments that frequently require assumptions about matters that are inherently uncertain. Many of these policies, estimates and related judgments are common in the insurance and financial services industries; others are specific to the Company’s business and operations. Actual results could differ from estimates.

The accompanying interim condensed consolidated financial statements include the accounts of MetLife USA, as well as partnerships and joint ventures in which the Company has control, and variable interest entities (“VIEs”) for which the Company is the primary beneficiary. Intercompany accounts and transactions have been eliminated.

The Company uses the equity method of accounting for equity securities when it has significant influence or at least 20% interest and for real estate joint ventures and other limited partnership interests (“investees”) when it has more than a minor ownership interest or more than a minor influence over the investee’s operations, but does not have a controlling financial interest. The Company generally recognizes its share of the investee’s earnings on a three-month lag in instances where the investee’s financial information is not sufficiently timely or when the investee’s reporting period differs from the Company’s reporting period. The Company uses the cost method of accounting for investments in which it has virtually no influence over the investee’s operations.

Certain amounts in the prior year periods’ interim condensed consolidated financial statements and related footnotes thereto have been reclassified to conform with the 2015 presentation as discussed throughout the Notes to the Interim Condensed Consolidated Financial Statements.

Since the Company is a member of a controlled group of affiliated companies, its results may not be indicative of those of a stand-alone entity.

The accompanying interim condensed consolidated financial statements are unaudited and reflect all adjustments (including normal recurring adjustments) necessary to present fairly the financial position, results of operations and cash flows for the interim periods presented in conformity with GAAP. Interim results are not necessarily indicative of full year performance. The December 31, 2014 consolidated balance sheet data was derived from audited consolidated financial statements included in the 2014 Annual Report, which include all disclosures required by GAAP. Therefore, these interim condensed consolidated financial statements should be read in conjunction with the consolidated financial statements of the Company included in the 2014 Annual Report.

Adoption of New Accounting Pronouncements

Effective January 1, 2015, the Company adopted guidance requiring repurchase-to-maturity transactions and repurchase financing arrangements to be accounted for as secured borrowings and providing for enhanced disclosures, including the nature of collateral pledged and the time to maturity. Certain interim period disclosures for repurchase agreements and securities lending transactions are not required until the second quarter of 2015. The adoption of this new guidance did not have a material impact on the Company’s consolidated financial statements.

Future Adoption of New Accounting Pronouncements

In May, 2015, the Financial Accounting Standards Board (“FASB”) issued new guidance on fair value measurement (Accounting Standards Update (“ASU”) 2015-07, Fair Value Measurement (Topic 820): Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent)), effective for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years and which should be applied retrospectively to all periods presented. Earlier application is permitted. The new amendments in this ASU remove the requirement to categorize within the fair value hierarchy all investments for which fair value is measured using the net asset value (“NAV”) per share practical expedient. In addition, the amendments remove the requirement to make certain disclosures for all investments that are eligible to be measured at fair value using the net asset value per share practical expedient. The Company is currently evaluating the impact of this guidance on its consolidated financial statements.

In April 2015, the FASB issued new guidance on accounting for fees paid in a cloud computing arrangement (ASU 2015-05, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement), effective for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. Early adoption of the new guidance is permitted and an entity can elect to adopt the guidance either: (1) prospectively to all arrangements entered into or materially modified after the effective date; or (2) retrospectively. The new guidance provides that all software licenses included in cloud computing arrangements be accounted for consistent with other licenses of intangible assets. However, if a cloud computing arrangement does not include a software license, the arrangement should be accounted for as a service contract, the accounting for which did not change. The Company is currently evaluating the impact of this guidance on its consolidated financial statements.

In April 2015, the FASB issued new guidance on the presentation of debt issuance costs (ASU 2015-03, Interest - Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs), effective for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years and should be applied retrospectively to all periods presented. Early adoption of the new guidance is permitted for financial statements that have not been previously issued. The new guidance will require that debt issuance costs be presented in the balance sheet as a direct deduction from the related debt liability rather than as an asset, consistent with debt discounts. However, the current recognition and measurement guidance for debt issuance costs are not affected by the new guidance. The Company is currently evaluating the impact of this guidance on its consolidated financial statements.

In February 2015, the FASB issued new guidance to improve consolidation guidance for legal entities (ASU 2015-02, Consolidation (Topic 810): Amendments to the Consolidation Analysis), effective for fiscal years beginning after December 15, 2015 and interim periods within those years and early adoption is permitted. The new standard is intended to improve targeted areas of the consolidation guidance for legal entities such as limited partnerships, limited liability corporations, and securitization structures. The amendments in this ASU affect the consolidation evaluation for reporting organizations. In addition, the amendments in this ASU simplify and improve current GAAP by reducing the number of consolidation models. The Company is currently evaluating the impact of this guidance on its consolidated financial statements.

In May 2014, the FASB issued a comprehensive new revenue recognition standard (ASU 2014‑09, Revenue from Contracts with Customers (Topic 606)), effective retrospectively for fiscal years beginning after December 15, 2016 and interim periods within those years. Early adoption of this standard is not permitted. The new guidance will supersede nearly all existing revenue recognition guidance under GAAP; however, it will not impact the accounting for insurance contracts, leases, financial instruments and guarantees. For those contracts that are impacted by the new guidance, the guidance will require an entity to recognize revenue upon the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The Company is currently evaluating the impact of this guidance on its consolidated financial statements.