Name:	cef_GeneralDescriptionOfRegistrantAbstract
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Balance Type:	na
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Description of changes contained within amended document.

No definition available.

Name:	dei_AmendmentDescription
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.

No definition available.

Name:	dei_AmendmentFlag
Namespace Prefix:	dei_
Data Type:	xbrli:booleanItemType
Balance Type:	na
Period Type:	duration

Area code of city

No definition available.

Name:	dei_CityAreaCode
Namespace Prefix:	dei_
Data Type:	xbrli:normalizedStringItemType
Balance Type:	na
Period Type:	duration

Cover page.

No definition available.

Name:	dei_CoverAbstract
Namespace Prefix:	dei_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

No definition available.

Name:	dei_DocumentType
Namespace Prefix:	dei_
Data Type:	dei:submissionTypeItemType
Balance Type:	na
Period Type:	duration

Address Line 1 such as Attn, Building Name, Street Name

No definition available.

Name:	dei_EntityAddressAddressLine1
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Data Type:	xbrli:normalizedStringItemType
Balance Type:	na
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Address Line 2 such as Street or Suite number

No definition available.

Name:	dei_EntityAddressAddressLine2
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Data Type:	xbrli:normalizedStringItemType
Balance Type:	na
Period Type:	duration

Name of the City or Town

No definition available.

Name:	dei_EntityAddressCityOrTown
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Balance Type:	na
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Code for the postal or zip code

No definition available.

Name:	dei_EntityAddressPostalZipCode
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Data Type:	xbrli:normalizedStringItemType
Balance Type:	na
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Name of the state or province.

No definition available.

Name:	dei_EntityAddressStateOrProvince
Namespace Prefix:	dei_
Data Type:	dei:stateOrProvinceItemType
Balance Type:	na
Period Type:	duration

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Number 240
-Section 12
-Subsection b-2

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Indicate if registrant meets the emerging growth company criteria.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Number 240
-Section 12
-Subsection b-2

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Data Type:	xbrli:booleanItemType
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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

No definition available.

Name:	dei_EntityFileNumber
Namespace Prefix:	dei_
Data Type:	dei:fileNumberItemType
Balance Type:	na
Period Type:	duration

The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Number 240
-Section 12
-Subsection b-2

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Namespace Prefix:	dei_
Data Type:	xbrli:normalizedStringItemType
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Local phone number for entity.

No definition available.

Name:	dei_LocalPhoneNumber
Namespace Prefix:	dei_
Data Type:	xbrli:normalizedStringItemType
Balance Type:	na
Period Type:	duration

Net asset value per share or per unit of investments in certain entities that calculate net asset value per share. Includes, but is not limited to, by unit, membership interest, or other ownership interest. Investment includes, but is not limited to, investment in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds. Excludes fair value disclosure.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
-SubTopic 830
-Name Accounting Standards Codification
-Section 55
-Paragraph 12
-Publisher FASB
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-Topic 946
-SubTopic 210
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-Topic 946
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-Subparagraph (a)
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-Topic 946
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-Topic 946
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-Subparagraph (SX 210.6-04(19))
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-Topic 946
-SubTopic 210
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NexPoint Capital, Inc. 8-K/A