2.4.0.82406403 - Disclosure - Fair Value (Quantitative Information) (Details)truefalsefalse1false USDfalsefalse$D2013Q2YTD_us-gaap_FairValueByAssetClassAxis_micc_UnitedStatesCorporateAndForeignCorporateSecuritiesMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_us-gaap_MarketApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00numberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2false USDfalsefalse$D2012Q4YTD_us-gaap_FairValueByAssetClassAxis_micc_UnitedStatesCorporateAndForeignCorporateSecuritiesMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_us-gaap_MarketApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2012-01-01T00:00:002012-12-31T00:00:00numberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$1false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse1false USDtruefalse$D2013Q2YTD_us-gaap_FairValueByAssetClassAxis_micc_UnitedStatesCorporateAndForeignCorporateSecuritiesMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_us-gaap_MarketApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseU.S. corporate and foreign corporate securities [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_UnitedStatesCorporateAndForeignCorporateSecuritiesMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberfalsefalseMarket Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MarketApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$nanafalse0U.S. corporate and foreign corporate securities [Member] | Minimum [Member] | Market Approach Valuation Technique [Member]2true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]3false 4micc_FairValueInputsDeltaSpreadAdjustmentsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse-0.0040-0.0040falsefalsefalse2truetruefalse0.00090.0009falsefalsefalsenum:percentItemTypepurePercentage of adjustment to the observed price for a similar asset or liability when an identical transaction does not exist, used as an input to measure fair value.No definition available.false0Delta spread adjustments4false 4us-gaap_FairValueInputsDiscountForLackOfMarketabilityus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00300.0030falsefalsefalse2truetruefalse0.00300.0030falsefalsefalsenum:percentItemTypepureAdjustment to the discount rate used to measure fair value for lack of ability to convert business interests into cash quickly.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false0Illiquidity premium5false 4micc_FairValueInputsOfferedQuotesMatrixPricingmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse9999USD$falsetruefalse2truefalsefalse100100USD$falsetruefalsenum:perShareItemTypedecimalMatrix Pricing - Price at which a dealer is willing to buy an instrument, used as an input to measure fair value.No definition available.false3Matrix Pricing - Offered quotes6false 4us-gaap_FairValueInputsOfferedQuotesus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse5050USD$falsetruefalse2truefalsefalse3535USD$falsetruefalsenum:perShareItemTypedecimalPrice at which a dealer is willing to buy an instrument, used as an input to measure fair value.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false3Offered quotes7false 4micc_FairValueInputsCreditSpreadsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse-0.0097-0.0097falsefalsefalse2truetruefalse-0.0157-0.0157falsefalsefalsenum:percentItemTypepureCredit SpreadsNo definition available.false0Credit spreads8false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3false USDtruefalse$D2013Q2YTD_us-gaap_FairValueByAssetClassAxis_micc_UnitedStatesCorporateAndForeignCorporateSecuritiesMember_us-gaap_RangeAxis_us-gaap_MaximumMember_us-gaap_ValuationTechniqueAxis_us-gaap_MarketApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseU.S. corporate and foreign corporate securities [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_UnitedStatesCorporateAndForeignCorporateSecuritiesMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberfalsefalseMarket Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MarketApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$nanafalse0U.S. corporate and foreign corporate securities [Member] | Maximum [Member] | Market Approach Valuation Technique [Member]9true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]10false 4micc_FairValueInputsDeltaSpreadAdjustmentsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.02400.0240falsefalsefalse2truetruefalse0.05000.0500falsefalsefalsenum:percentItemTypepurePercentage of adjustment to the observed price for a similar asset or liability when an identical transaction does not exist, used as an input to measure fair value.No definition available.false0Delta spread adjustments11false 4us-gaap_FairValueInputsDiscountForLackOfMarketabilityus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00300.0030falsefalsefalse2truetruefalse0.00300.0030falsefalsefalsenum:percentItemTypepureAdjustment to the discount rate used to measure fair value for lack of ability to convert business interests into cash quickly.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false0Illiquidity premium12false 4micc_FairValueInputsOfferedQuotesMatrixPricingmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse100100USD$falsetruefalse2truefalsefalse100100USD$falsetruefalsenum:perShareItemTypedecimalMatrix Pricing - Price at which a dealer is willing to buy an instrument, used as an input to measure fair value.No definition available.false3Matrix Pricing - Offered quotes13false 4us-gaap_FairValueInputsOfferedQuotesus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse103103USD$falsetruefalse2truefalsefalse555555USD$falsetruefalsenum:perShareItemTypedecimalPrice at which a dealer is willing to buy an instrument, used as an input to measure fair value.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false3Offered quotes14false 4micc_FairValueInputsCreditSpreadsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.05350.0535falsefalsefalse2truetruefalse0.08760.0876falsefalsefalsenum:percentItemTypepureCredit SpreadsNo definition available.false0Credit spreads15false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse5false USDtruefalse$D2013Q2YTD_us-gaap_FairValueByAssetClassAxis_micc_UnitedStatesCorporateAndForeignCorporateSecuritiesMember_us-gaap_RangeAxis_us-gaap_WeightedAverageMember_us-gaap_ValuationTechniqueAxis_us-gaap_MarketApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseU.S. corporate and foreign corporate securities [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_UnitedStatesCorporateAndForeignCorporateSecuritiesMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseWeighted Average [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_WeightedAverageMemberus-gaap_RangeAxisexplicitMemberfalsefalseMarket Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MarketApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$nanafalse0U.S. corporate and foreign corporate securities [Member] | Weighted Average [Member] | Market Approach Valuation Technique [Member]16true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]17false 4micc_FairValueInputsDeltaSpreadAdjustmentsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00700.0070falsefalsefalse2truetruefalse0.01050.0105falsefalsefalsenum:percentItemTypepurePercentage of adjustment to the observed price for a similar asset or liability when an identical transaction does not exist, used as an input to measure fair value.No definition available.false0Delta spread adjustments18false 4us-gaap_FairValueInputsDiscountForLackOfMarketabilityus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00300.0030falsefalsefalse2truetruefalse0.00300.0030falsefalsefalsenum:percentItemTypepureAdjustment to the discount rate used to measure fair value for lack of ability to convert business interests into cash quickly.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false0Illiquidity premium19false 4micc_FairValueInputsOfferedQuotesMatrixPricingmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse100100USD$falsetruefalse2truefalsefalse100100USD$falsetruefalsenum:perShareItemTypedecimalMatrix Pricing - Price at which a dealer is willing to buy an instrument, used as an input to measure fair value.No definition available.false3Matrix Pricing - Offered quotes20false 4us-gaap_FairValueInputsOfferedQuotesus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse8686USD$falsetruefalse2truefalsefalse9696USD$falsetruefalsenum:perShareItemTypedecimalPrice at which a dealer is willing to buy an instrument, used as an input to measure fair value.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false3Offered quotes21false 4micc_FairValueInputsCreditSpreadsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.02390.0239falsefalsefalse2truetruefalse0.02820.0282falsefalsefalsenum:percentItemTypepureCredit SpreadsNo definition available.false0Credit spreads22false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse7false USDtruefalse$D2013Q2YTD_us-gaap_FairValueByAssetClassAxis_us-gaap_ResidentialMortgageBackedSecuritiesMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_us-gaap_MarketApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRMBS [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ResidentialMortgageBackedSecuritiesMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberfalsefalseMarket Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MarketApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$nanafalse0RMBS [Member] | Minimum [Member] | Market Approach Valuation Technique [Member]23true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]24false 4micc_FairValueInputsQuotedPricesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse8484USD$falsetruefalse2truefalsefalse100100USD$falsetruefalsenum:perShareItemTypedecimalQuoted pricesNo definition available.false3Quoted prices25false 4micc_FairValueInputsCreditSpreadsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse-0.0110-0.0110falsefalsefalse2truetruefalse0.00400.0040falsefalsefalsenum:percentItemTypepureCredit SpreadsNo definition available.false0Credit spreads26false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse9false USDtruefalse$D2013Q2YTD_us-gaap_FairValueByAssetClassAxis_us-gaap_ResidentialMortgageBackedSecuritiesMember_us-gaap_RangeAxis_us-gaap_MaximumMember_us-gaap_ValuationTechniqueAxis_us-gaap_MarketApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRMBS [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ResidentialMortgageBackedSecuritiesMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberfalsefalseMarket Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MarketApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$nanafalse0RMBS [Member] | Maximum [Member] | Market Approach Valuation Technique [Member]27true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]28false 4micc_FairValueInputsQuotedPricesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse106106USD$falsetruefalse2truefalsefalse100100USD$falsetruefalsenum:perShareItemTypedecimalQuoted pricesNo definition available.false3Quoted prices29false 4micc_FairValueInputsCreditSpreadsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.29840.2984falsefalsefalse2truetruefalse0.23670.2367falsefalsefalsenum:percentItemTypepureCredit SpreadsNo definition available.false0Credit spreads30false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse11false USDtruefalse$D2013Q2YTD_us-gaap_FairValueByAssetClassAxis_us-gaap_ResidentialMortgageBackedSecuritiesMember_us-gaap_RangeAxis_us-gaap_WeightedAverageMember_us-gaap_ValuationTechniqueAxis_us-gaap_MarketApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRMBS [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ResidentialMortgageBackedSecuritiesMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseWeighted Average [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_WeightedAverageMemberus-gaap_RangeAxisexplicitMemberfalsefalseMarket Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MarketApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$nanafalse0RMBS [Member] | Weighted Average [Member] | Market Approach Valuation Technique [Member]31true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]32false 4micc_FairValueInputsQuotedPricesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse9898USD$falsetruefalse2truefalsefalse100100USD$falsetruefalsenum:perShareItemTypedecimalQuoted pricesNo definition available.false3Quoted prices33false 4micc_FairValueInputsCreditSpreadsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.02790.0279falsefalsefalse2truetruefalse0.04360.0436falsefalsefalsenum:percentItemTypepureCredit SpreadsNo definition available.false0Credit spreads34false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse13false USDtruefalse$D2013Q2YTD_us-gaap_FairValueByAssetClassAxis_us-gaap_CommercialMortgageBackedSecuritiesMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_us-gaap_MarketApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseCMBS [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommercialMortgageBackedSecuritiesMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberfalsefalseMarket Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MarketApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$nanafalse0CMBS [Member] | Minimum [Member] | Market Approach Valuation Technique [Member]35true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]36false 4micc_FairValueInputsQuotedPricesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse22USD$falsetruefalse2truefalsefalse100100USD$falsetruefalsenum:perShareItemTypedecimalQuoted pricesNo definition available.false3Quoted prices37false 4us-gaap_FairValueInputsOfferedQuotesus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse100100USD$falsetruefalse2falsefalsefalse00falsefalsefalsenum:perShareItemTypedecimalPrice at which a dealer is willing to buy an instrument, used as an input to measure fair value.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false3Offered quotes38false 4micc_FairValueInputsCreditSpreadsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00060.0006falsefalsefalse2truetruefalse0.00100.0010falsefalsefalsenum:percentItemTypepureCredit SpreadsNo definition available.false0Credit spreads39false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse15false USDtruefalse$D2013Q2YTD_us-gaap_FairValueByAssetClassAxis_us-gaap_CommercialMortgageBackedSecuritiesMember_us-gaap_RangeAxis_us-gaap_MaximumMember_us-gaap_ValuationTechniqueAxis_us-gaap_MarketApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseCMBS [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommercialMortgageBackedSecuritiesMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberfalsefalseMarket Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MarketApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$nanafalse0CMBS [Member] | Maximum [Member] | Market Approach Valuation Technique [Member]40true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]41false 4micc_FairValueInputsQuotedPricesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse104104USD$falsetruefalse2truefalsefalse104104USD$falsetruefalsenum:perShareItemTypedecimalQuoted pricesNo definition available.false3Quoted prices42false 4us-gaap_FairValueInputsOfferedQuotesus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse100100USD$falsetruefalse2falsefalsefalse00falsefalsefalsenum:perShareItemTypedecimalPrice at which a dealer is willing to buy an instrument, used as an input to measure fair value.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false3Offered quotes43false 4micc_FairValueInputsCreditSpreadsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.14120.1412falsefalsefalse2truetruefalse0.91640.9164falsefalsefalsenum:percentItemTypepureCredit SpreadsNo definition available.false0Credit spreads44false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse17false USDtruefalse$D2013Q2YTD_us-gaap_FairValueByAssetClassAxis_us-gaap_CommercialMortgageBackedSecuritiesMember_us-gaap_RangeAxis_us-gaap_WeightedAverageMember_us-gaap_ValuationTechniqueAxis_us-gaap_MarketApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseCMBS [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommercialMortgageBackedSecuritiesMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseWeighted Average [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_WeightedAverageMemberus-gaap_RangeAxisexplicitMemberfalsefalseMarket Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MarketApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$nanafalse0CMBS [Member] | Weighted Average [Member] | Market Approach Valuation Technique [Member]45true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]46false 4micc_FairValueInputsQuotedPricesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse9797USD$falsetruefalse2truefalsefalse102102USD$falsetruefalsenum:perShareItemTypedecimalQuoted pricesNo definition available.false3Quoted prices47false 4us-gaap_FairValueInputsOfferedQuotesus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse100100USD$falsetruefalse2falsefalsefalse00falsefalsefalsenum:perShareItemTypedecimalPrice at which a dealer is willing to buy an instrument, used as an input to measure fair value.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false3Offered quotes48false 4micc_FairValueInputsCreditSpreadsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.05160.0516falsefalsefalse2truetruefalse0.04130.0413falsefalsefalsenum:percentItemTypepureCredit SpreadsNo definition available.false0Credit spreads49false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse19false USDtruefalse$D2013Q2YTD_us-gaap_FairValueByAssetClassAxis_us-gaap_AssetBackedSecuritiesMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_us-gaap_MarketApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseABS [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_AssetBackedSecuritiesMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberfalsefalseMarket Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MarketApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$nanafalse0ABS [Member] | Minimum [Member] | Market Approach Valuation Technique [Member]50true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]51false 4micc_FairValueInputsQuotedPricesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse00USD$falsetruefalse2truefalsefalse9797USD$falsetruefalsenum:perShareItemTypedecimalQuoted pricesNo definition available.false3Quoted prices52false 4us-gaap_FairValueInputsOfferedQuotesus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse5050USD$falsetruefalse2truefalsefalse5050USD$falsetruefalsenum:perShareItemTypedecimalPrice at which a dealer is willing to buy an instrument, used as an input to measure fair value.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false3Offered quotes53false 4micc_FairValueInputsCreditSpreadsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00300.0030falsefalsefalse2truetruefalse0.00000.0000falsefalsefalsenum:percentItemTypepureCredit SpreadsNo definition available.false0Credit spreads54false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse21false USDtruefalse$D2013Q2YTD_us-gaap_FairValueByAssetClassAxis_us-gaap_AssetBackedSecuritiesMember_us-gaap_RangeAxis_us-gaap_MaximumMember_us-gaap_ValuationTechniqueAxis_us-gaap_MarketApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseABS [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_AssetBackedSecuritiesMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberfalsefalseMarket Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MarketApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$nanafalse0ABS [Member] | Maximum [Member] | Market Approach Valuation Technique [Member]55true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]56false 4micc_FairValueInputsQuotedPricesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse104104USD$falsetruefalse2truefalsefalse102102USD$falsetruefalsenum:perShareItemTypedecimalQuoted pricesNo definition available.false3Quoted prices57false 4us-gaap_FairValueInputsOfferedQuotesus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse111111USD$falsetruefalse2truefalsefalse111111USD$falsetruefalsenum:perShareItemTypedecimalPrice at which a dealer is willing to buy an instrument, used as an input to measure fair value.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false3Offered quotes58false 4micc_FairValueInputsCreditSpreadsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.08750.0875falsefalsefalse2truetruefalse0.09000.0900falsefalsefalsenum:percentItemTypepureCredit SpreadsNo definition available.false0Credit spreads59false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse23false USDtruefalse$D2013Q2YTD_us-gaap_FairValueByAssetClassAxis_us-gaap_AssetBackedSecuritiesMember_us-gaap_RangeAxis_us-gaap_WeightedAverageMember_us-gaap_ValuationTechniqueAxis_us-gaap_MarketApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseABS [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_AssetBackedSecuritiesMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseWeighted Average [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_WeightedAverageMemberus-gaap_RangeAxisexplicitMemberfalsefalseMarket Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MarketApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$nanafalse0ABS [Member] | Weighted Average [Member] | Market Approach Valuation Technique [Member]60true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]61false 4micc_FairValueInputsQuotedPricesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse101101USD$falsetruefalse2truefalsefalse100100USD$falsetruefalsenum:perShareItemTypedecimalQuoted pricesNo definition available.false3Quoted prices62false 4us-gaap_FairValueInputsOfferedQuotesus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse9898USD$falsetruefalse2truefalsefalse100100USD$falsetruefalsenum:perShareItemTypedecimalPrice at which a dealer is willing to buy an instrument, used as an input to measure fair value.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false3Offered quotes63false 4micc_FairValueInputsCreditSpreadsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.02790.0279falsefalsefalse2truetruefalse0.01520.0152falsefalsefalsenum:percentItemTypepureCredit SpreadsNo definition available.false0Credit spreads64false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse25false truefalseD2013Q2YTD_us-gaap_FairValueByAssetClassAxis_us-gaap_InterestRateContractMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseInterest rate contracts [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_InterestRateContractMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Interest rate contracts [Member] | Minimum [Member] | Income Approach Valuation Technique [Member]65true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]66false 4micc_FairValueInputsSwapYieldmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.02380.0238falsefalsefalse2truetruefalse0.02210.0221falsefalsefalsenum:percentItemTypepureSwap YieldNo definition available.false0Swap yield67false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse27false truefalseD2013Q2YTD_us-gaap_FairValueByAssetClassAxis_us-gaap_InterestRateContractMember_us-gaap_RangeAxis_us-gaap_MaximumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseInterest rate contracts [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_InterestRateContractMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Interest rate contracts [Member] | Maximum [Member] | Income Approach Valuation Technique [Member]68true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]69false 4micc_FairValueInputsSwapYieldmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.04020.0402falsefalsefalse2truetruefalse0.03530.0353falsefalsefalsenum:percentItemTypepureSwap YieldNo definition available.false0Swap yield70false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse29false truefalseD2013Q2YTD_us-gaap_FairValueByAssetClassAxis_us-gaap_CreditRiskContractMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseCredit contracts [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CreditRiskContractMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Credit contracts [Member] | Minimum [Member] | Income Approach Valuation Technique [Member]71true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]72false 4micc_FairValueInputsCreditSpreadsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00990.0099falsefalsefalse2truetruefalse0.01000.0100falsefalsefalsenum:percentItemTypepureCredit SpreadsNo definition available.false0Credit spreads73false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse31false truefalseD2013Q2YTD_us-gaap_FairValueByAssetClassAxis_us-gaap_CreditRiskContractMember_us-gaap_RangeAxis_us-gaap_MaximumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseCredit contracts [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CreditRiskContractMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Credit contracts [Member] | Maximum [Member] | Income Approach Valuation Technique [Member]74true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]75false 4micc_FairValueInputsCreditSpreadsmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00990.0099falsefalsefalse2truetruefalse0.01000.0100falsefalsefalsenum:percentItemTypepureCredit SpreadsNo definition available.false0Credit spreads76false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse33false truefalseD2013Q2YTD_us-gaap_FairValueByAssetClassAxis_us-gaap_EquityContractMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_micc_PresentValueTechniquesOrOptionPricingModelMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEquity market contracts [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityContractMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberfalsefalsePresent Value techniques or option pricing model [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldimicc_PresentValueTechniquesOrOptionPricingModelMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Equity market contracts [Member] | Minimum [Member] | Present Value techniques or option pricing model [Member]77true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]78false 4micc_FairValueInputsVolatilitymicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.170.17falsefalsefalse2truetruefalse0.180.18falsefalsefalsenum:percentItemTypepureVolatilityNo definition available.false0Volatility79false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse35false truefalseD2013Q2YTD_us-gaap_FairValueByAssetClassAxis_us-gaap_EquityContractMember_us-gaap_RangeAxis_us-gaap_MaximumMember_us-gaap_ValuationTechniqueAxis_micc_PresentValueTechniquesOrOptionPricingModelMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEquity market contracts [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityContractMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberfalsefalsePresent Value techniques or option pricing model [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldimicc_PresentValueTechniquesOrOptionPricingModelMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Equity market contracts [Member] | Maximum [Member] | Present Value techniques or option pricing model [Member]80true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]81false 4micc_FairValueInputsVolatilitymicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.270.27falsefalsefalse2truetruefalse0.260.26falsefalsefalsenum:percentItemTypepureVolatilityNo definition available.false0Volatility82false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse37false truefalseD2013Q2YTD_us-gaap_FairValueByAssetClassAxis_micc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEmbedded derivatives direct and assumed guaranteed benefits [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Embedded derivatives direct and assumed guaranteed benefits [Member] | Minimum [Member] | Income Approach Valuation Technique [Member]83true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]84false 4micc_FairValueInputsUtilizationRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.200.20falsefalsefalse2truetruefalse0.200.20falsefalsefalsenum:percentItemTypepureFair value inputs utilization rates.No definition available.false0Utilization rates85false 4micc_FairValueInputsWithdrawalRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00070.0007falsefalsefalse2truetruefalse0.00070.0007falsefalsefalsenum:percentItemTypepureFair value inputs withdrawal rates.No definition available.false0Withdrawal rates86false 4micc_FairValueInputsLongTermEquityVolatilitiesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.17400.1740falsefalsefalse2truetruefalse0.17400.1740falsefalsefalsenum:percentItemTypepureFair value inputs long-term equity volatilities.No definition available.false0Long-term equity volatilities87false 4micc_FairValueInputsNonperformanceRiskSpreadmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00070.0007falsefalsefalse2truetruefalse0.00100.0010falsefalsefalsenum:percentItemTypepureFair value inputs nonperformance risk spread.No definition available.false0Nonperformance risk spread88false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse39false truefalseD2013Q2YTD_micc_LapseRatesDurationRangeAxis_micc_LapseRatesDurationRangeOneMember_us-gaap_FairValueByAssetClassAxis_micc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEmbedded derivatives direct and assumed guaranteed benefits [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseDurations 1-10 [Member]micc_LapseRatesDurationRangeAxisxbrldihttp://xbrl.org/2006/xbrldimicc_LapseRatesDurationRangeOneMembermicc_LapseRatesDurationRangeAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Embedded derivatives direct and assumed guaranteed benefits [Member] | Minimum [Member] | Income Approach Valuation Technique [Member] | Durations 1-10 [Member]89true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]90false 4micc_FairValueInputsLapseRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00500.0050falsefalsefalse2truetruefalse0.00500.0050falsefalsefalsenum:percentItemTypepureFair value inputs lapse rates.No definition available.false0Lapse rates91false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse41false truefalseD2013Q2YTD_micc_LapseRatesDurationRangeAxis_micc_LapseRatesDurationRangeTwoMember_us-gaap_FairValueByAssetClassAxis_micc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEmbedded derivatives direct and assumed guaranteed benefits [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseDurations 11-20 [Member]micc_LapseRatesDurationRangeAxisxbrldihttp://xbrl.org/2006/xbrldimicc_LapseRatesDurationRangeTwoMembermicc_LapseRatesDurationRangeAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Embedded derivatives direct and assumed guaranteed benefits [Member] | Minimum [Member] | Income Approach Valuation Technique [Member] | Durations 11-20 [Member]92true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]93false 4micc_FairValueInputsLapseRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.030.03falsefalsefalse2truetruefalse0.030.03falsefalsefalsenum:percentItemTypepureFair value inputs lapse rates.No definition available.false0Lapse rates94false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse43false truefalseD2013Q2YTD_micc_LapseRatesDurationRangeAxis_micc_LapseRatesDurationRangeThreeMember_us-gaap_FairValueByAssetClassAxis_micc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEmbedded derivatives direct and assumed guaranteed benefits [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseDurations 21-116 [Member]micc_LapseRatesDurationRangeAxisxbrldihttp://xbrl.org/2006/xbrldimicc_LapseRatesDurationRangeThreeMembermicc_LapseRatesDurationRangeAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Embedded derivatives direct and assumed guaranteed benefits [Member] | Minimum [Member] | Income Approach Valuation Technique [Member] | Durations 21-116 [Member]95true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]96false 4micc_FairValueInputsLapseRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.030.03falsefalsefalse2truetruefalse0.030.03falsefalsefalsenum:percentItemTypepureFair value inputs lapse rates.No definition available.false0Lapse rates97false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse45false truefalseD2013Q2YTD_micc_MortalityRatesRangeAxis_micc_MortalityRatesRangeOneMember_us-gaap_FairValueByAssetClassAxis_micc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEmbedded derivatives direct and assumed guaranteed benefits [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseAges 0-40 [Member]micc_MortalityRatesRangeAxisxbrldihttp://xbrl.org/2006/xbrldimicc_MortalityRatesRangeOneMembermicc_MortalityRatesRangeAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Embedded derivatives direct and assumed guaranteed benefits [Member] | Minimum [Member] | Income Approach Valuation Technique [Member] | Ages 0-40 [Member]98true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]99false 4micc_FairValueInputsMortalityRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.000.00falsefalsefalse2truetruefalse0.000.00falsefalsefalsenum:percentItemTypepureMortality Rates.No definition available.false0Mortality rates100false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse47false truefalseD2013Q2YTD_micc_MortalityRatesRangeAxis_micc_MortalityRatesRangeTwoMember_us-gaap_FairValueByAssetClassAxis_micc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEmbedded derivatives direct and assumed guaranteed benefits [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseAges 41-60 [Member]micc_MortalityRatesRangeAxisxbrldihttp://xbrl.org/2006/xbrldimicc_MortalityRatesRangeTwoMembermicc_MortalityRatesRangeAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Embedded derivatives direct and assumed guaranteed benefits [Member] | Minimum [Member] | Income Approach Valuation Technique [Member] | Ages 41-60 [Member]101true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]102false 4micc_FairValueInputsMortalityRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00050.0005falsefalsefalse2truetruefalse0.00050.0005falsefalsefalsenum:percentItemTypepureMortality Rates.No definition available.false0Mortality rates103false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse49false truefalseD2013Q2YTD_micc_MortalityRatesRangeAxis_micc_MortalityRatesRangeThreeMember_us-gaap_FairValueByAssetClassAxis_micc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMember_us-gaap_RangeAxis_us-gaap_MinimumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEmbedded derivatives direct and assumed guaranteed benefits [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseAges 61-115 [Member]micc_MortalityRatesRangeAxisxbrldihttp://xbrl.org/2006/xbrldimicc_MortalityRatesRangeThreeMembermicc_MortalityRatesRangeAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Embedded derivatives direct and assumed guaranteed benefits [Member] | Minimum [Member] | Income Approach Valuation Technique [Member] | Ages 61-115 [Member]104true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]105false 4micc_FairValueInputsMortalityRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00320.0032falsefalsefalse2truetruefalse0.00320.0032falsefalsefalsenum:percentItemTypepureMortality Rates.No definition available.false0Mortality rates106false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse51false truefalseD2013Q2YTD_us-gaap_FairValueByAssetClassAxis_micc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMember_us-gaap_RangeAxis_us-gaap_MaximumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEmbedded derivatives direct and assumed guaranteed benefits [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Embedded derivatives direct and assumed guaranteed benefits [Member] | Maximum [Member] | Income Approach Valuation Technique [Member]107true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]108false 4micc_FairValueInputsUtilizationRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.500.50falsefalsefalse2truetruefalse0.500.50falsefalsefalsenum:percentItemTypepureFair value inputs utilization rates.No definition available.false0Utilization rates109false 4micc_FairValueInputsWithdrawalRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.100.10falsefalsefalse2truetruefalse0.100.10falsefalsefalsenum:percentItemTypepureFair value inputs withdrawal rates.No definition available.false0Withdrawal rates110false 4micc_FairValueInputsLongTermEquityVolatilitiesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.250.25falsefalsefalse2truetruefalse0.250.25falsefalsefalsenum:percentItemTypepureFair value inputs long-term equity volatilities.No definition available.false0Long-term equity volatilities111false 4micc_FairValueInputsNonperformanceRiskSpreadmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00610.0061falsefalsefalse2truetruefalse0.00670.0067falsefalsefalsenum:percentItemTypepureFair value inputs nonperformance risk spread.No definition available.false0Nonperformance risk spread112false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse53false truefalseD2013Q2YTD_micc_LapseRatesDurationRangeAxis_micc_LapseRatesDurationRangeOneMember_us-gaap_FairValueByAssetClassAxis_micc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMember_us-gaap_RangeAxis_us-gaap_MaximumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEmbedded derivatives direct and assumed guaranteed benefits [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseDurations 1-10 [Member]micc_LapseRatesDurationRangeAxisxbrldihttp://xbrl.org/2006/xbrldimicc_LapseRatesDurationRangeOneMembermicc_LapseRatesDurationRangeAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Embedded derivatives direct and assumed guaranteed benefits [Member] | Maximum [Member] | Income Approach Valuation Technique [Member] | Durations 1-10 [Member]113true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]114false 4micc_FairValueInputsLapseRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse1.001.00falsefalsefalse2truetruefalse1.001.00falsefalsefalsenum:percentItemTypepureFair value inputs lapse rates.No definition available.false0Lapse rates115false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse55false truefalseD2013Q2YTD_micc_LapseRatesDurationRangeAxis_micc_LapseRatesDurationRangeTwoMember_us-gaap_FairValueByAssetClassAxis_micc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMember_us-gaap_RangeAxis_us-gaap_MaximumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEmbedded derivatives direct and assumed guaranteed benefits [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseDurations 11-20 [Member]micc_LapseRatesDurationRangeAxisxbrldihttp://xbrl.org/2006/xbrldimicc_LapseRatesDurationRangeTwoMembermicc_LapseRatesDurationRangeAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Embedded derivatives direct and assumed guaranteed benefits [Member] | Maximum [Member] | Income Approach Valuation Technique [Member] | Durations 11-20 [Member]116true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]117false 4micc_FairValueInputsLapseRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse1.001.00falsefalsefalse2truetruefalse1.001.00falsefalsefalsenum:percentItemTypepureFair value inputs lapse rates.No definition available.false0Lapse rates118false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse57false truefalseD2013Q2YTD_micc_LapseRatesDurationRangeAxis_micc_LapseRatesDurationRangeThreeMember_us-gaap_FairValueByAssetClassAxis_micc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMember_us-gaap_RangeAxis_us-gaap_MaximumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEmbedded derivatives direct and assumed guaranteed benefits [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseDurations 21-116 [Member]micc_LapseRatesDurationRangeAxisxbrldihttp://xbrl.org/2006/xbrldimicc_LapseRatesDurationRangeThreeMembermicc_LapseRatesDurationRangeAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Embedded derivatives direct and assumed guaranteed benefits [Member] | Maximum [Member] | Income Approach Valuation Technique [Member] | Durations 21-116 [Member]119true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]120false 4micc_FairValueInputsLapseRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse1.001.00falsefalsefalse2truetruefalse1.001.00falsefalsefalsenum:percentItemTypepureFair value inputs lapse rates.No definition available.false0Lapse rates121false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse59false truefalseD2013Q2YTD_micc_MortalityRatesRangeAxis_micc_MortalityRatesRangeOneMember_us-gaap_FairValueByAssetClassAxis_micc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMember_us-gaap_RangeAxis_us-gaap_MaximumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEmbedded derivatives direct and assumed guaranteed benefits [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseAges 0-40 [Member]micc_MortalityRatesRangeAxisxbrldihttp://xbrl.org/2006/xbrldimicc_MortalityRatesRangeOneMembermicc_MortalityRatesRangeAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Embedded derivatives direct and assumed guaranteed benefits [Member] | Maximum [Member] | Income Approach Valuation Technique [Member] | Ages 0-40 [Member]122true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]123false 4micc_FairValueInputsMortalityRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00100.0010falsefalsefalse2truetruefalse0.00100.0010falsefalsefalsenum:percentItemTypepureMortality Rates.No definition available.false0Mortality rates124false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse61false truefalseD2013Q2YTD_micc_MortalityRatesRangeAxis_micc_MortalityRatesRangeTwoMember_us-gaap_FairValueByAssetClassAxis_micc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMember_us-gaap_RangeAxis_us-gaap_MaximumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEmbedded derivatives direct and assumed guaranteed benefits [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseAges 41-60 [Member]micc_MortalityRatesRangeAxisxbrldihttp://xbrl.org/2006/xbrldimicc_MortalityRatesRangeTwoMembermicc_MortalityRatesRangeAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Embedded derivatives direct and assumed guaranteed benefits [Member] | Maximum [Member] | Income Approach Valuation Technique [Member] | Ages 41-60 [Member]125true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]126false 4micc_FairValueInputsMortalityRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse0.00640.0064falsefalsefalse2truetruefalse0.00640.0064falsefalsefalsenum:percentItemTypepureMortality Rates.No definition available.false0Mortality rates127false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse63false truefalseD2013Q2YTD_micc_MortalityRatesRangeAxis_micc_MortalityRatesRangeThreeMember_us-gaap_FairValueByAssetClassAxis_micc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMember_us-gaap_RangeAxis_us-gaap_MaximumMember_us-gaap_ValuationTechniqueAxis_us-gaap_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000733076duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseEmbedded derivatives direct and assumed guaranteed benefits [Member]us-gaap_FairValueByAssetClassAxisxbrldihttp://xbrl.org/2006/xbrldimicc_EmbeddedDerivativesDirectAndAssumedGuaranteedBenefitsMemberus-gaap_FairValueByAssetClassAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberfalsefalseIncome Approach Valuation Technique [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseAges 61-115 [Member]micc_MortalityRatesRangeAxisxbrldihttp://xbrl.org/2006/xbrldimicc_MortalityRatesRangeThreeMembermicc_MortalityRatesRangeAxisexplicitMembernumberStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Embedded derivatives direct and assumed guaranteed benefits [Member] | Maximum [Member] | Income Approach Valuation Technique [Member] | Ages 61-115 [Member]128true 3us-gaap_FairValueInputsAssetsQuantitativeInformationLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets, Quantitative Information [Line Items]129false 4micc_FairValueInputsMortalityRatesmicc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truetruefalse1.001.00falsefalsefalse2truetruefalse1.001.00falsefalsefalsenum:percentItemTypepureMortality Rates.No definition available.false0Mortality ratesfalseFair Value (Quantitative Information) (Details) (USD $)UnKnownUnKnownNoRoundingUnKnowntruefalsefalseSheethttp://www.metlife.com/role/FairValueQuantitativeInformationDetails2129