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</LabelSeparator><Level>1</Level><ElementName>us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText /><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>xbrli:stringItemType</ElementDataType><SimpleDataType>string</SimpleDataType><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Organization, Consolidation and Presentation of Financial Statements [Abstract]</Label></Row><Row FlagID="0"><Id>2</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><Level>2</Level><ElementName>us-gaap_OrganizationConsolidationBasisOfPresentationBusinessDescriptionAndAccountingPoliciesTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><PreferredLabelRole>verboseLabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="D2013Q2YTD" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;div style="font-family:Times New Roman;font-size:10pt;"&gt;&lt;div style="line-height:120%;padding-top:12px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;font-weight:bold;"&gt;1.  Business, Basis of Presentation and Summary of Significant Accounting Policies&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;font-style:italic;font-weight:bold;"&gt;Business&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;text-align:justify;text-indent:24px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&amp;#8220;MICC&amp;#8221; or the &amp;#8220;Company&amp;#8221; refers to MetLife Insurance Company of Connecticut, a Connecticut corporation incorporated in 1863, and its subsidiaries, including MetLife Investors USA Insurance Company (&amp;#8220;MLI-USA&amp;#8221;). MetLife Insurance Company of Connecticut is a wholly-owned subsidiary of MetLife, Inc. (&amp;#8220;MetLife&amp;#8221;). The Company offers individual annuities, individual life insurance, and institutional protection and asset accumulation products.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;text-align:justify;text-indent:24px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;The Company is organized into &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;two&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; segments: Retail and Corporate Benefit Funding.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;font-style:italic;font-weight:bold;"&gt;Basis of Presentation&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;text-align:justify;text-indent:24px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (&amp;#8220;GAAP&amp;#8221;) 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&amp;#8217;s business and operations. Actual results could differ from estimates.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;text-align:justify;text-indent:24px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;The accompanying interim condensed consolidated financial statements include the accounts of MetLife Insurance Company of Connecticut and its subsidiaries, as well as partnerships and joint ventures in which the Company has control, and variable interest entities (&amp;#8220;VIEs&amp;#8221;) for which the Company is the primary beneficiary. Intercompany accounts and transactions have been eliminated.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;text-align:justify;text-indent:24px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;The Company uses the equity method of accounting for investments in equity securities when it has significant influence or at least a &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;20%&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; interest and for investments in real estate joint ventures and other limited partnership interests (&amp;#8220;investees&amp;#8221;) when it has more than a minor ownership interest or more than minor influence over the investee&amp;#8217;s operations, but does not have a controlling financial interest. The Company generally recognizes its share of the investee&amp;#8217;s earnings on a three-month lag in instances where the investee&amp;#8217;s financial information is not sufficiently timely or when the investee&amp;#8217;s reporting period differs from the Company&amp;#8217;s reporting period. The Company uses the cost method of accounting for investments in which it has virtually no influence over the investee&amp;#8217;s operations.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;text-align:justify;text-indent:24px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;Certain amounts in the prior year periods&amp;#8217; interim condensed consolidated financial statements and related footnotes thereto have been reclassified to conform with the 2013 presentation as discussed throughout the Notes to the Interim Condensed Consolidated Financial Statements.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;text-align:justify;text-indent:24px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;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.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;text-align:justify;text-indent:24px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;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, 2012 consolidated balance sheet data was derived from audited consolidated financial statements included in MetLife Insurance Company of Connecticut&amp;#8217;s Annual Report on Form 10-K for the year ended December 31, 2012 (the &amp;#8220;2012 Annual Report&amp;#8221;), filed with the U.S. Securities and Exchange Commission (&amp;#8220;SEC&amp;#8221;), 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 2012 Annual Report.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;font-style:italic;font-weight:bold;"&gt;Adoption of New Accounting Pronouncements&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;text-align:justify;text-indent:24px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;Effective January&amp;#160;1, 2013, the Company adopted new guidance regarding comprehensive income that requires an entity to provide information about the amounts reclassified out of accumulated other comprehensive income (loss) (&amp;#8220;AOCI&amp;#8221;) by component. In addition, an entity is required to present, either on the face of the statement where net income is presented or in the notes, significant amounts reclassified out of AOCI by the respective line items of net income but only if the amount reclassified is required under GAAP to be reclassified to net income in its entirety in the same reporting period. For other amounts that are not required under GAAP to be reclassified in their entirety to net income, an entity is required to cross-reference to other disclosures required under GAAP that provide additional detail about those amounts. The adoption was prospectively applied and resulted in additional disclosures in Note &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;7&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;text-align:justify;text-indent:24px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;Effective January 1, 2013, the Company adopted new guidance regarding balance sheet offsetting disclosures which requires an entity to disclose information about offsetting and related arrangements for derivatives, including bifurcated embedded derivatives, repurchase and reverse repurchase agreements, and securities borrowing and lending transactions, to enable users of its financial statements to understand the effects of those arrangements on its financial position. Entities are required to disclose both gross information and net information about both instruments and transactions eligible for offset in the statement of financial position and instruments and transactions subject to an agreement similar to a master netting arrangement. The adoption was retrospectively applied and resulted in additional disclosures related to derivatives in Note &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;5&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;font-style:italic;font-weight:bold;"&gt;Future Adoption of New Accounting Pronouncements&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;text-align:justify;text-indent:24px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;In July 2013, the Financial Accounting Standards Board (&amp;#8220;FASB&amp;#8221;) issued new guidance regarding derivatives (Accounting Standards Update (&amp;#8220;ASU&amp;#8221;) 2013-10, &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;font-style:italic;"&gt;Derivatives and Hedging (Topic 815): Inclusion of the Fed Funds Effective Swap Rate (or Overnight Index Swap Rate (&amp;#8220;OIS&amp;#8221;)) as a Benchmark Interest Rate for Hedge Accounting Purposes&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;), effective prospectively for qualifying new or redesignated hedging relationships entered into on or after July 17, 2013. The amendments permit the Fed Funds Effective Swap Rate (or OIS) to be used as a U.S. benchmark interest rate for hedge accounting purposes under Topic 815, in addition to the United States Treasury and London Inter-Bank Offered Rate. Also, the amendments remove the restriction on using different benchmark rates for similar hedges. The Company has adopted this new guidance in July 2013. The new guidance will not have a material impact on the consolidated financial statements upon adoption, but may impact the selection of benchmark interest rates for hedging relationships in the future.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;text-align:justify;text-indent:24px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;In March 2013, the FASB issued new guidance regarding foreign currency (ASU 2013-05, &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;font-style:italic;"&gt;Foreign Currency Matters (Topic 830): Parent&amp;#8217;s Accounting for the Cumulative Translation Adjustment upon Derecognition of Certain Subsidiaries or Groups of Assets within a Foreign Entity or of an Investment in a Foreign Entity)&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;, effective prospectively for fiscal years and interim reporting periods within those years beginning after December&amp;#160;15, 2013. The amendments require an entity that ceases to have a controlling financial interest in a subsidiary or group of assets within a foreign entity to apply the guidance in Subtopic 830-30, &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;font-style:italic;"&gt;Foreign Currency Matters &amp;#8212; Translation of Financial Statements,&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; to release any related cumulative translation adjustment into net income. Accordingly, the cumulative translation adjustment should be released into net income only if the sale or transfer results in the complete or substantially complete liquidation of the foreign entity in which the subsidiary or group of assets had resided. For an equity method investment that is a foreign entity, the partial sale guidance in section 830-30-40, &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;font-style:italic;"&gt;Derecognition,&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; still applies. As such, a pro rata portion of the cumulative translation adjustment should be released into net income upon a partial sale of such an equity method investment. The Company is currently evaluating the impact of this guidance on its consolidated financial statements.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:12px;text-align:justify;text-indent:24px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;In February 2013, the FASB issued new guidance regarding liabilities (ASU 2013-04, &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;font-style:italic;"&gt;Liabilities (Topic 405): Obligations Resulting from Joint and Several Liability Arrangements for Which the Total Amount of the Obligation Is Fixed at the Reporting Date)&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;, effective retrospectively for fiscal years beginning after December&amp;#160;15, 2013 and interim periods within those years. The amendments require an entity to measure obligations resulting from joint and several liability arrangements for which the total amount of the obligation within the scope of the guidance is fixed at the reporting date, as the sum of the amount the reporting entity agreed to pay on the basis of its arrangement among its co-obligors and any additional amount the reporting entity expects to pay on behalf of its co-obligors. In addition, the amendments require an entity to disclose the nature and amount of the obligation, as well as other information about the obligations. The Company is currently evaluating the impact of this guidance on its consolidated financial statements.&lt;/font&gt;&lt;/div&gt;&lt;/div&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for the general note to the financial statements for the reporting entity which may include, descriptions of the basis of presentation, business description, significant accounting policies, consolidations, reclassifications, new pronouncements not yet adopted and changes in accounting principles.</ElementDefenition><ElementReferences>No definition available.</ElementReferences><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Business, Basis of Presentation and Summary of Significant Accounting Policies</Label></Row></Rows><Footnotes /><IsEquityReport>false</IsEquityReport><ReportName>Business, Basis of Presentation and Summary of Significant Accounting Policies</ReportName><MonetaryRoundingLevel>UnKnown</MonetaryRoundingLevel><SharesRoundingLevel>UnKnown</SharesRoundingLevel><PerShareRoundingLevel>UnKnown</PerShareRoundingLevel><ExchangeRateRoundingLevel>UnKnown</ExchangeRateRoundingLevel><HasCustomUnits>true</HasCustomUnits><IsEmbedReport>false</IsEmbedReport><IsMultiCurrency>false</IsMultiCurrency><ReportType>Sheet</ReportType><RoleURI>http://www.metlife.com/role/BusinessBasisOfPresentationAndSummaryOfSignificantAccountingPolicies</RoleURI><NumberOfCols>1</NumberOfCols><NumberOfRows>2</NumberOfRows></InstanceReport>
