Long-Term Debt and Credit Facilities - Covenants and Guarantees (Details)	9 Months Ended
Sep. 30, 2024 USD ($) indenture
Letter of Credit \| Uncommitted Letter of Credit Facility
Long-term Debt and Credit Facilities
Maximum borrowing capacity \| $	$ 225,000,000
Line of Credit and Term Loan \| Minimum
Long-term Debt and Credit Facilities
Interest coverage ratio	2.00
Senior Notes
Long-term Debt and Credit Facilities
Number of indentures \| indenture	4
Redemption price (as a percent)	101.00%
Senior Notes \| Level 3 Financing, Inc.
Long-term Debt and Credit Facilities
Redemption price (as a percent)	101.00%
Last Day of Each Fiscal Quarter
Long-term Debt and Credit Facilities
Maximum total net leverage ratio	5.75
Fiscal Quarter Ending After December 31, 2024 \| Line of Credit and Term Loan
Long-term Debt and Credit Facilities
Maximum total net leverage ratio	5.50
Fiscal Quarter Ending After December 31, 2025 \| Line of Credit and Term Loan
Long-term Debt and Credit Facilities
Maximum total net leverage ratio	5.25

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