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The number of equity-based payment instruments, excluding stock (or unit) options, that are expected to vest in fourth fiscal year following current fiscal year.

No definition available.

Name:	nref_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsVestingYearFour
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Data Type:	xbrli:sharesItemType
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The number of equity-based payment instruments, excluding stock (or unit) options, that are expected to vest in next fiscal year following current fiscal year.

No definition available.

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Data Type:	xbrli:sharesItemType
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The number of equity-based payment instruments, excluding stock (or unit) options, that are expected to vest in third fiscal year following current fiscal year.

No definition available.

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Data Type:	xbrli:sharesItemType
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The number of equity-based payment instruments, excluding stock (or unit) options, that are expected to vest in second fiscal year following current fiscal year.

No definition available.

Name:	nref_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsVestingYearTwo
Namespace Prefix:	nref_
Data Type:	xbrli:sharesItemType
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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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