| REAL ESTATE SECURITIES - Holdings in an Unrealized Loss Position and the Associated Intent to Sell (Details 2) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2015 | |||||
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| RE Securities No Intent to Sell Credit Impaired [Member] | ||||||
| Fair Value | $ 1,383us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = nct_RESecuritiesNoIntentToSellCreditImpairedMember | |||||
| Amortized Cost Basis | 1,649nct_AvailableForSaleDebtSecuritiesAmortizedCostBasis1 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = nct_RESecuritiesNoIntentToSellCreditImpairedMember | |||||
| Unrealized Credit Losses | (48)nct_RESecuritiesUnrealizedCreditLosses / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = nct_RESecuritiesNoIntentToSellCreditImpairedMember | [1] | ||||
| Unrealized Non-Credit Losses | (266)nct_RESecuritiesUnrealizedNoncreditLosses / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = nct_RESecuritiesNoIntentToSellCreditImpairedMember | [2] | ||||
| RE Securities No Intent to Sell Non Credit Impaired [Member] | ||||||
| Fair Value | 2,094us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = nct_RESecuritiesNoIntentToSellNonCreditImpairedMember | |||||
| Amortized Cost Basis | 2,121nct_AvailableForSaleDebtSecuritiesAmortizedCostBasis1 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = nct_RESecuritiesNoIntentToSellNonCreditImpairedMember | |||||
| Unrealized Non-Credit Losses | (27)nct_RESecuritiesUnrealizedNoncreditLosses / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = nct_RESecuritiesNoIntentToSellNonCreditImpairedMember | [2] | ||||
| Securities in an Unrealized Loss Position [Member] | ||||||
| Fair Value | 3,477us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = nct_SecuritiesUnrealizedLossMember | |||||
| Amortized Cost Basis | 3,770nct_AvailableForSaleDebtSecuritiesAmortizedCostBasis1 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = nct_SecuritiesUnrealizedLossMember | |||||
| Unrealized Credit Losses | (48)nct_RESecuritiesUnrealizedCreditLosses / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = nct_SecuritiesUnrealizedLossMember | |||||
| Unrealized Non-Credit Losses | $ (293)nct_RESecuritiesUnrealizedNoncreditLosses / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = nct_SecuritiesUnrealizedLossMember | |||||
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- Definition This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. No definition available. 
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- Definition Gross Unrealized losses on real estate securities that are in an unrealized loss position due to credit and appear on the intent to sell schedule. No definition available. 
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- Definition Gross Unrealized losses on real estate securities that are in an unrealized loss position due to non-credit issues and appear on the intent to sell schedule. No definition available. 
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- Definition This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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