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Description of the business: - Financial instruments (Details) - USD ($) $ in Millions	Sep. 30, 2025	Apr. 11, 2025	May 02, 2024
Level 2 | Interest rate swap
Description of the business:
long-term liability	$ 13.8
Senior unsecured 2027 notes | Level 2
Description of the business:
Senior notes	$ 450.0
Interest rate (as a percent)	7.00%
Senior notes, fair value	$ 447.8
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	$ 298.5
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	$ 583.5
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	$ 213.0
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:
Senior notes	$ 174.4
Interest rate (as a percent)	6.646%
Senior notes, fair value	$ 174.5

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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