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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
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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