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v3.23.2

Summary of Significant Accounting Policies - Summary of Properties (Details) ft² in Thousands, $ in Thousands | Jun. 30, 2023 USD ($) ft² | Dec. 31, 2022 USD ($) | [2]
--- | --- | --- | ---
Property, Plant and Equipment [Line Items] |  |  |
Investments at fair value | $ 3,179,465 | [1] | $ 3,221,247
New Mountain Net Lease Corporation |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Fair Value | 120,342 |  |
New Mountain Net Lease Corporation | NM NL Holdings LP / NM GP Holdco LLC |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Fair Value | $ 96,813 |  |
New Mountain Net Lease Corporation | NM CLFX LP |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Total Square Feet | ft² | 423 |  |
Fair Value | $ 14,065 |  |
New Mountain Net Lease Corporation | NM YI, LLC |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Total Square Feet | ft² | 212 |  |
Fair Value | $ 9,464 |  |
New Mountain Net Lease Corporation | NM APP Canada Corp |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Fair Value | $ 7 |  |
[1] | New Mountain Finance Corporation (the "Company") generally acquires its investments in private transactions exempt from registration under the Securities Act of 1933, as amended (the "Securities Act"). These investments are generally subject to certain limitations on resale, and may be deemed to be "restricted securities" under the Securities Act
[2] | New Mountain Finance Corporation (the "Company") generally acquires its investments in private transactions exempt from registration under the Securities Act of 1933, as amended (the "Securities Act"). These investments are generally subject to certain limitations on resale, and may be deemed to be "restricted securities" under the Securities Act.

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