| DERIVATIVES - Schedule of gains (losses) recorded in relation to derivatives (Details 1) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | |
|---|---|---|
| Mar. 31, 2015 | Mar. 31, 2014 | |
| Cash flow hedges | ||
| Cash flow hedge income statement location - reclassifications | Interest expense | |
| Deferred hedge gain (loss) reclassified from AOCI into earnings | $ 19nct_DeferredHedgeGainLossReclassifiedFromAOCIIntoEarnings | $ 13nct_DeferredHedgeGainLossReclassifiedFromAOCIIntoEarnings | 
| Amount of loss reclassified from AOCI into income (effective portion) | (708)us-gaap_DerivativeInstrumentsLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortion | (1,280)us-gaap_DerivativeInstrumentsLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortion | 
| Non-hedge income statement location | Other income (loss) | |
| Gain recognized related to interest rate swaps | 292us-gaap_GainLossOnInterestRateDerivativeInstrumentsNotDesignatedAsHedgingInstruments | 2,075us-gaap_GainLossOnInterestRateDerivativeInstrumentsNotDesignatedAsHedgingInstruments | 
| Gain (loss) on settlement of TBAs | (4,871)nct_SettlementOfTBAs | |
| Amount of unrealized gain (loss) recognized in OCI on derivatives (effective portion) | (33)us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet | (77)us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet | 
| TBAs [Member] | ||
| Cash flow hedges | ||
| Non-hedge income statement location | Gain (loss) on settlement investments, net | |
| Gain (loss) on settlement of TBAs | (4,871)nct_SettlementOfTBAs / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_OtherContractMember | |
| TBAs [Member] | Not designated as hedging instrument [Member] | ||
| Cash flow hedges | ||
| Non-hedge income statement location | Other income (loss) | |
| Gain recognized related to non-hedge | (1,321)us-gaap_GainLossOnSaleOfDerivatives / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_OtherContractMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember | |
| Linked Transactions [Member] | ||
| Cash flow hedges | ||
| Non-hedge income statement location | Other income (loss) | |
| Gain recognized related to non-hedge | $ 10,673us-gaap_GainLossOnSaleOfDerivatives / us-gaap_DerivativeByNatureAxis = nct_LinkedTransactionDerivativeAssetMember | |
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- Definition Deferred gain (loss) of derivative instruments from accumulated other comprehensive income into earnings for derivative instruments designated and qualifying as hedging instruments. No definition available. 
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- Definition Amount of income (loss) recognized on the settlement of TBAs in the income statement. No definition available. 
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- Definition The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition The effective portion of loss reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition The caption on the income statement reflecting the gain (loss) on derivative instruments not designated as hedging instruments. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Identifies the line item(s) where the net gain (loss) on cash flow hedges is reported in the statement of income or other statement of financial performance. Includes description for amounts included in other comprehensive income. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of gain (loss) included in earnings for the period from the increase (decrease) in fair value of interest rate derivatives not designated as hedging instruments. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
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