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4us-gaap_InterestPayableCurrentAndNoncurrentus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse58870005887000falsefalsefalse2truefalsefalse65610006561000falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6truefalsefalse279000279000falsefalsefalse7truefalsefalse15000001500000falsefalsefalse8truefalsefalse15000001500000falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryCarrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15(5)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.15(a)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Subparagraph a -Article 7 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Subparagraph 5 -Article 9 false2Accrued interest payable7false 4wmc_DebtInstrumentTermwmc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse001 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Most repos involve obligations of the federal government or its agencies, but other financial instruments, such as commercial paper, banker's acceptances, and negotiable certificates of deposit, are sometimes used in repos.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13(1)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13 -Subparagraph 1 -Article 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=7472769&loc=d3e9760-107771 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 140 -Paragraph 100 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(m)(1)(a)(i)) -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-BRD -Paragraph 36 -IssueDate 2006-05-01 -Chapter 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Repurchase Agreement Borrowings10false 5us-gaap_ShortTermDebtWeightedAverageInterestRateus-gaap_truenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.00440.0044falsefalsefalse2truetruefalse0.00480.0048falsefalsefalse3truetruefalse0.00400.0040falsefalsefalse4truetruefalse0.00480.0048falsefalsefalse5truetruefalse0.01790.0179falsefalsefalse6falsetruefalse00falsefalsefalse7falsetruefalse00falsefalsefalse8falsetruefalse00falsefalsefalse9falsetruefalse00falsefalsefalse10falsetruefalse00falsefalsefalsenum:percentItemTypepureReflects the calculation as of the balance sheet date of the average interest rate weighted by the amount of short-term debt outstanding by type or by instrument at that time.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph b -Article 5 false0Weighted Average Interest Rate on Borrowings Outstanding at end of period (as a percent)11false 5wmc_DebtInstrumentWeightedAverageRemainingMaturityPeriodwmc_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse0031 daysfalsefalsefalse2falsefalsefalse0019 daysfalsefalsefalse3falsefalsefalse0031 daysfalsefalsefalse4falsefalsefalse0019 daysfalsefalsefalse5falsefalsefalse0022 daysfalsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalsexbrli:durationItemTypenaRepresents the weighted average remaining term of debt instrument.No definition available.false0Weighted Average Remaining Maturity (days)falseBorrowings under Repurchase Agreements (Details) (USD $)NoRoundingUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.westernassetmcc.com/role/DisclosureBorrowingsUnderRepurchaseAgreementsDetails1011