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Represents allowance for loan losses expressed as basis points of the outstanding principal balance of residential loans held in securitization trusts.

No definition available.

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Represents the percentage of delinquent loans that are currently under some form of modified payment plan.

No definition available.

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The aggregate number of delinquent loans.

No definition available.

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Amount of principal due on delinquent mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and other-than-temporary impairments), for loans accounted for as debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

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Balance Type:	credit
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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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-Publisher FASB
-Name Accounting Standards Codification
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Name:	srt_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis=nymt_ResidentialDistressedMortgageLoansHeldInSecuritizationTrustMember
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Name:	us-gaap_LoanRestructuringModificationAxis=us-gaap_PaymentDeferralMember
Namespace Prefix:
Data Type:	na
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Name:	srt_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis=nymt_ResidentialMortgageLoansHeldInSecuritizationTrustsAndRealEstateOwnedHeldInResidentialSecuritizationMember
Namespace Prefix:
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Name:	us-gaap_CreditLossStatusAxis=us-gaap_FinancialAssetAcquiredWithCreditDeteriorationMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis=nymt_DistressedResidentialMortgageLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ResidentialMortgageMember
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