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Description of the business: - Financial instruments (Details) - USD ($) $ in Millions	Jun. 30, 2025	Apr. 11, 2025	Dec. 31, 2024	May 02, 2024
Interest rate swap
Description of the business:
Fair value of interest rate swaps	$ 13.6		$ 4.0
Level 2 \| Interest rate swap
Description of the business:
long-term liability	13.6
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Description of the business:
Senior notes	$ 450.0
Interest rate (as a percent)	7.00%
Senior notes, fair value	$ 450.0
Senior Unsecured Mirror Notes due 2027 \| Level 2
Description of the business:
Senior notes	$ 300.0
Interest rate (as a percent)	7.00%
Senior notes, fair value	$ 300.0
Senior secured 2026 Notes
Description of the business:
Interest rate (as a percent)	3.50%
Senior secured 2026 Notes \| Level 2
Description of the business:
Interest rate (as a percent)	6.50%
Senior notes, fair value	$ 591.0
Face amount	$ 600.0
Existing IPv4 Notes
Description of the business:
Interest rate (as a percent)	7.924%			7.924%
Face amount	$ 206.0			$ 206.0
Existing IPv4 Notes \| Level 2
Description of the business:
Interest rate (as a percent)	7.924%
Senior notes, fair value	$ 211.3
Face amount	$ 206.0
IPv4 New Notes
Description of the business:
Interest rate (as a percent)	6.646%	6.646%
Face amount	$ 174.4	$ 174.4
IPv4 New Notes \| Level 2
Description of the business:
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Interest rate (as a percent)	6.646%
Senior notes, fair value	$ 175.4