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Long-term debt: (Details) $ in Thousands |  |  |  |  |  |  | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 04, 2025 USD ($) | Apr. 11, 2025 USD ($) | Jun. 15, 2024 | Jun. 11, 2024 USD ($) | May 02, 2024 USD ($) | May 07, 2021 USD ($) | Nov. 30, 2024 USD ($) | Jun. 30, 2024 USD ($) | May 31, 2024 USD ($) | Nov. 30, 2023 USD ($) | May 31, 2023 USD ($) | Nov. 30, 2022 USD ($) | Jun. 30, 2022 USD ($) | May 31, 2022 USD ($) | Dec. 31, 2025 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Jun. 17, 2025 USD ($) | Jun. 22, 2022 USD ($)
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of secured debt |  | $ 170,500 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss on extinguishment & redemption of 2026 notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,606 |  |  |  |
Debt instrument restricted value |  | 72,600 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument unrestricted value |  | $ 97,900 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease payments |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 33,843 | $ 74,632 | $ 77,362 |  |
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration] |  |  |  |  |  |  |  |  |  |  |  |  |  |  | us-gaap:SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember |  |  |  |
Interest rate swap |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,100 | 22,300 |  |  |
Interest rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.50% |  |  |  |
Net liability, prepaid expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 18,300 |  |  |
Net liability, other long term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4,000 |  |  |
Interest rate swap | Cash |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Margin deposits |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,100 |  |  |  |
Interest rate swap | Unrestricted cash |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Margin deposits |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 200 |  |  |  |
Interest rate swap | Accrued and other current liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of interest rate swaps |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4,300 |  |  |  |
2027 Mirror Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  | $ 300,000 |  |  |  | $ 300,000 |  |  |  |  |  |  | $ 300,000 |  |  |  |
Interest rate (as a percent) |  |  |  |  |  |  |  | 7.00% |  |  |  |  |  |  | 7.00% |  |  |  |
Maturity date |  |  |  |  |  |  |  | Jun. 15, 2027 |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of secured debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 291,900 |  |  |  |
Minimum percentage of principal amount entitled for redemption |  |  |  | 90.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease payments |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 114,600 |  |  |  |
Percentage of face value |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 98.50% |  |  |  |
2027 Mirror Notes | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of principal amount considered as default debt |  |  |  | 25.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2027 Mirror Notes | Redemption of some or all the notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Redemption price percentage of principal amount redeemed |  |  | 103.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2027 Mirror Notes | If certain events have occurred |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchase price, percentage of principal amount repurchased |  |  | 101.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2027 Mirror Notes | If certain events have not occurred |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchase price, percentage of principal amount repurchased |  |  |  | 100.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2027 Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  |  |  |  |  |  |  | $ 450,000 |  | $ 450,000 |  |  |  | $ 450,000
Interest rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  | 7.00% |  | 7.00% |  |  |  |
Maturity date |  |  |  |  |  |  |  |  |  |  |  |  | Jun. 15, 2027 |  |  |  |  |  |
Proceeds from issuance of secured debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 446,000 |  |  |  |
Loss on extinguishment & redemption of 2026 notes | $ 5,600 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Discount on issuance of debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,700 |  |  |  |
Debt costs |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,300 |  |  |  |
2027 Notes | June 15, 2024 to June 14, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Redemption price percentage of principal amount redeemed |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 103.50% |  |  |  |
2026 Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  | $ 500,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.50% |  |  |  |
Redemption value |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 500,000 |  |  |  |
Amount of net proceeds from offering | 507,300 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Principal amount | 500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount of accrued interest redeemed | 2,200 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Discount on issuance of debt |  |  |  |  |  | 1,800 |  |  |  |  |  |  |  |  |  |  |  |  |
Debt costs |  |  |  |  |  | 1,300 |  |  |  |  |  |  |  |  |  |  |  |  |
Amount of settlement payment | $ 5,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds |  |  |  |  |  | $ 496,900 |  |  |  |  |  |  |  |  |  |  |  |  |
Secured IPv4 notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  | $ 380,400 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of secured debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 170,479 | 198,426 |  |  |
Debt costs |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4,000 | $ 7,600 |  |  |
Senior secured 2032 notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 600,000 |  |  | $ 600,000 |
Interest rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6.50% |  |  | 6.50% |
Proceeds from issuance of secured debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 597,842 |  |  |  |
Repurchase price in cash, percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100.00% |  |  |  |
Minimum percentage of principal amount entitled for redemption |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 90.00% |  |  |  |
Debt costs |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,200 |  |  |  |
Senior secured 2032 notes | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of principal amount considered as default debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 25.00% |  |  |  |
Consolidated leverage ratio |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |
Senior secured 2032 notes | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consolidated leverage ratio |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6 |  |  |  |
Senior secured 2032 notes | Redemption of some or all the notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchase price, percentage of principal amount repurchased |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100.00% |  |  |  |
Senior secured 2032 notes | Issuers may redeem up to 40% of notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Redemption price percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 106.50% |  |  |  |
Repurchase price, percentage of principal amount repurchased |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 40.00% |  |  |  |
Senior secured 2032 notes | Redemption after July 1, 2028 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchase price, percentage of principal amount repurchased |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 103.25% |  |  |  |
Senior secured 2032 notes | Change in control accompanied by certain rating events |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchase price, percentage of principal amount repurchased |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 101.00% |  |  |  |
Existing IPv4 Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  | $ 206,000 |  |  |  |  |  |  |  |  |  | $ 206,000 |  |  |  |
Interest rate (as a percent) |  |  |  |  | 7.924% |  |  |  |  |  |  |  |  |  | 7.924% |  |  |  |
Maturity date |  |  |  |  | May 31, 2054 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of secured debt |  |  |  |  | $ 198,400 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional interest accrued on percentage of principal amount |  |  |  |  | 5.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of noteholders voting rights to amend covenants |  | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Existing IPv4 Notes | Base Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument basis spread on variable rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5.00% |  |  |  |
Existing IPv4 Notes | US Treasury (UST) Interest Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument basis spread on variable rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.40% |  |  |  |
Existing IPv4 Notes | Issuance Of Additional Class Notes | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consolidated leverage ratio |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Existing IPv4 Notes | Issuance Of Additional Class Notes | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consolidated leverage ratio |  |  |  |  | 6.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Existing IPv4 Notes | Substitute New Ipv4 Addresses | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consolidated leverage ratio |  | 1 |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Existing IPv4 Notes | Substitute New Ipv4 Addresses | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consolidated leverage ratio |  | 7.25 |  |  | 6.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Existing IPv4 Notes | Dispose Of Ipv Addresses Owned By Ipv Issuer Member Dispose Of Ipv Addresses Owned By Ipv Issuer | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consolidated leverage ratio |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Existing IPv4 Notes | Dispose Of Ipv Addresses Owned By Ipv Issuer Member Dispose Of Ipv Addresses Owned By Ipv Issuer | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consolidated leverage ratio |  |  |  |  | 7.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |
IPv4 New Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  | $ 174,400 |  |  |  |  |  |  |  |  |  |  |  |  | $ 174,400 |  |  |  |
Interest rate (as a percent) |  | 6.646% |  |  |  |  |  |  |  |  |  |  |  |  | 6.646% |  |  |  |
Maturity date |  | Apr. 30, 2055 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restriction on restricted cash |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 26,900 |  |  |  |
Additional interest accrued on percentage of principal amount |  | 5.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
IPv4 New Notes | Base Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument basis spread on variable rate |  | 5.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
IPv4 New Notes | US Treasury (UST) Interest Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument basis spread on variable rate |  | 3.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
IPv4 New Notes | Issuance Of Additional Class Notes | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consolidated leverage ratio |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
IPv4 New Notes | Issuance Of Additional Class Notes | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consolidated leverage ratio |  | 7.25 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
IPv4 New Notes | Dispose Of Ipv Addresses Owned By Ipv Issuer Member Dispose Of Ipv Addresses Owned By Ipv Issuer | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consolidated leverage ratio |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
IPv4 New Notes | Dispose Of Ipv Addresses Owned By Ipv Issuer Member Dispose Of Ipv Addresses Owned By Ipv Issuer | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consolidated leverage ratio |  | 7.25 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Installment One | Interest rate swap |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payment made to counter party |  |  |  |  |  |  |  |  | $ 19,600 |  |  |  |  |  |  |  |  |  |
Net proceeds |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 21,500 |  |  |  |  |
Installment Two | Interest rate swap |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payment made to counter party |  |  |  |  |  |  |  |  |  |  | $ 24,200 |  |  |  |  |  |  |  |
Net proceeds |  |  |  |  |  |  | $ 19,600 |  |  | $ 24,200 |  | $ 21,500 |  |  |  |  |  |  |

X
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- Definition Indebtedness divided by net capital. + References No definition available. + Details
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