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Summary of Significant Accounting Policies - Schedule of Properties (Details) - New Mountain Net Lease Corporation ft² in Thousands, $ in Thousands | Jun. 30, 2025 USD ($) ft²
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Property, Plant and Equipment [Line Items] |
Fair value | $ 114,240
NM NL Holdings LP / NM GP Holdco LLC |
Property, Plant and Equipment [Line Items] |
Fair value | $ 105,366
NM YI, LLC |
Property, Plant and Equipment [Line Items] |
Total square feet | ft² | 212
Fair value | $ 8,874

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- Definition Fair value portion of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-13 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2E -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2E Reference 5: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 100 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-100 + Details
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