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Description of the business and summary of significant accounting policies: - Restricted cash and interest rate swap agreement (Details) - USD ($) $ in Thousands | Dec. 31, 2025 | Dec. 31, 2024
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Description of the business and summary of significant accounting policies: |  |
Restricted cash | $ 56,597 | $ 29,430
Secured IPv4 notes |  |
Description of the business and summary of significant accounting policies: |  |
Restricted cash | 52,500 | 7,100
Interest rate swap | Level 2 | Restricted cash |  |
Description of the business and summary of significant accounting policies: |  |
Fair value of interest rate swaps | $ 4,100 | $ 22,300

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