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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, 2024	Dec. 31, 2023
Description of the business:
Additional restricted cash	$ 29,430	$ 38,689
Secured IPv4 notes
Description of the business:
Additional restricted cash	7,100
Interest rate swap | Level 2 | Restricted cash
Description of the business:
Fair value of interest rate swaps	$ 22,300	$ 38,700

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