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Related Parties (Details) - USD ($) $ / shares in Units, $ in Thousands |  |  |  |  |  | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 29, 2025 | Jul. 01, 2024 | Nov. 01, 2021 | Oct. 31, 2021 | Mar. 30, 2020 | Jun. 30, 2025 | Oct. 31, 2023 | Oct. 30, 2023 | May 04, 2020 | May 03, 2020
Investments in Majority-owned Subsidiaries |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |
Shares redeemed for a promissory note (in shares) |  |  |  |  | 105,030 |  |  |  |  |
Redemption of shares paid-in-kind |  |  |  |  | $ 11,315 |  |  |  |  |
Common Stock | New Mountain Net Lease Corporation |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |
Sale of stock, number of shares issued (in shares) |  |  |  |  | 105,030 |  |  |  |  |
Sale of stock, price per share (in dollars per share) |  |  |  |  | $ 107.73 |  |  |  |  |
Sale of stock, consideration received |  |  |  |  | $ 11,315 |  |  |  |  |
Common Stock | New Mountain Net Lease Corporation | Investments in Majority-owned Subsidiaries |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |
Sale of stock, price per share (in dollars per share) |  | $ 73.39 |  |  |  |  |  |  |  |
Sale of stock, consideration received |  | $ 4,666 |  |  |  |  |  |  |  |
Shares sold (in shares) |  | 63,575 |  |  |  |  |  |  |  |
Common Stock | Affiliate Of Investment Adviser | New Mountain Net Lease Corporation |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |
Sale of stock, number of shares issued (in shares) |  | 63,575 |  |  |  |  |  |  |  |
Sale of stock, price per share (in dollars per share) |  | $ 73.39 |  |  |  |  |  |  |  |
Sale of stock, consideration received |  | $ 4,666 |  |  |  |  |  |  |  |
Affiliates | Credit Facility | Revolving Credit Facility | Unsecured Management Company Revolver |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  | $ 30,000 | $ 100,000 | $ 100,000 | $ 50,000 | $ 50,000 | $ 30,000
Investment Management Agreement | Affiliates |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |
Base management fee percentage | 1.25% |  | 1.40% | 1.75% |  | 1.25% |  |  |  |

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