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Description of the business and summary of significant accounting policies: - Acquisition of Sprint Communications (Details) |  | 1 Months Ended | 3 Months Ended | 12 Months Ended
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May 01, 2023 USD ($) installment | Apr. 30, 2024 USD ($) | Mar. 31, 2024 USD ($) | Sep. 30, 2023 USD ($) | Dec. 31, 2024 USD ($) country GB MB | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Description of the business: |  |  |  |  |  |  |
Number of countries entity operates | country |  |  |  |  | 56 |  |
Pre-tax loss |  |  |  |  | $ 259,649,000 | $ (1,219,477,000) | $ (26,376,000)
Estimated payment related to acquired short-term lease obligations | $ 157,200,000 |  |  |  |  |  |
Estimated Purchase Agreement payment to be received, amount of discount |  |  |  |  | 5,755,000 | 13,725,000 |
Lease liability |  |  |  |  | 359,176,000 |  |
Acquisition related costs |  |  |  |  | 21,407,000 | 18,492,000 | 2,248,000
Adjustment to reclassify, right-of-use leased assets |  |  |  | $ 24,900,000 |  |  |
Adjustment to reclassify operating lease liabilities to finance lease liability |  |  |  | 160,900,000 |  |  |
Unfavorable lease liabilities |  |  |  | 160,900,000 |  |  |
Optical fiber and rights of way |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Total property and equipment |  |  |  |  | 369,200,000 |  |
Commercial Agreement |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Amount due to the seller |  |  |  |  | 2,600,000 | 1,600,000 |
Amount due from the seller recorded during the period |  |  |  |  | 14,700,000 | 23,900,000 |
IP Transit Services Agreement | T-Mobile USA, Inc., |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Amount payable | 700,000,000 |  |  |  | 700,000,000 |  |
Amortization of discount resulted in interest income |  |  |  |  | 23,800,000 | 26,800,000 |
Amounts due from Seller - IP Transit Services Agreement, amount of discount | 79,600,000 |  |  |  |  |  |
Consideration paid |  |  |  |  | $ 204,200,000 | 204,200,000 |
IP Transit Services Agreement | Equal monthly installments during the first year after the Closing | T-Mobile USA, Inc., |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Amount payable | 350,000,000 |  |  |  |  |  |
IP Transit Services Agreement | Equal monthly installments over the subsequent 42 months | T-Mobile USA, Inc., |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Amount payable | 350,000,000 |  |  |  |  |  |
IP Transit Services Agreement | Per Month During First Year After Closing Date | T-Mobile USA, Inc., |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Amount payable | 29,200,000 |  |  |  |  |  |
IP Transit Services Agreement | Per Month Over Subsequent Forty Two Months | T-Mobile USA, Inc., |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Amount payable | $ 8,300,000 |  |  |  |  |  |
Transition Services Agreement |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Agreement term (in years) | 2 years |  |  |  |  |  |
Extension period (in years) | 1 year |  |  |  |  |  |
Period of prior written notice (in days) | 30 days |  |  |  |  |  |
Number of days' written notice to terminate the agreement |  |  |  |  | 30 days |  |
Period after which a notice for termination of agreement can be sent (in days) |  |  |  |  | 90 days |  |
Maturity period from receipt of the related invoice for amount billed under the agreement (in days) |  |  |  |  | 30 days |  |
Amount due to the seller recorded during the period |  |  |  |  | $ 27,200,000 | 284,100,000 |
Amount paid to the seller |  |  |  |  | 93,800,000 | 217,200,000 |
Amount due to the seller |  |  |  |  | 500,000 | 66,900,000 |
Amount due from the seller |  |  |  |  | 100,000 | 4,500,000 |
Amount due from the seller recorded during the period |  |  |  |  | 1,100,000 | 6,200,000 |
Amount received from the seller |  |  |  |  | 1,300,000 | 6,000,000 |
Wireline Network Holdings LLC |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Revenue |  |  |  |  |  | 283,300,000 |
Pre-tax loss |  |  |  |  |  | 234,500,000 |
Cash and cash equivalents | $ 47,074,000 |  |  |  |  |  |
Estimated Purchase Agreement payment to be received, amount of discount | 8,392,000 |  |  |  |  |  |
Reduction in short term lease payment |  |  | $ 24,200,000 |  |  |  |
Amounts due from Seller - IP Transit Services Agreement, amount of discount | 79,610,000 |  |  |  |  |  |
Consideration paid | 1,000 |  |  |  | 1,000 |  |
Acquisition related costs |  |  |  |  | 9,100,000 | 2,300,000 | $ 2,200,000
Total property and equipment | 965,715,000 |  |  |  | 965,700,000 |  |
Wireline Network Holdings LLC | Buyer |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Short term lease payment |  |  |  |  | 5,000,000 |  |
Wireline Network Holdings LLC | Purchase Agreement |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Amount payable | 1,000 |  |  |  |  |  |
Severance costs |  |  |  |  | 28,600,000 |  |
Acquisition related costs |  |  |  |  | 13,600,000 |  |
Wireline Network Holdings LLC | Purchase Agreement | Buyer |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Cash and cash equivalents | 43,400,000 |  |  |  |  |  |
Working capital adjustment | 61,100,000 |  |  |  |  |  |
Additional working capital adjustment |  |  |  | 5,000,000 |  |  |
Estimated payment related to acquired short-term lease obligations | $ 28,100,000 |  |  |  |  |  |
Estimated payment related to acquired short-term lease obligations, number of equal payments | installment | 4 |  |  |  |  |  |
Estimated Purchase Agreement payment to be received, amount of discount | $ 8,400,000 |  |  |  |  |  |
Amortization of discount resulted in interest income |  |  |  | 4,800,000 |  |  |
Amortization of income (expenses) |  |  |  |  | 700,000 | 1,900,000 |
Short-term lease payments |  |  | 17,000,000 |  |  |  |
Severance costs |  |  | 7,200,000 |  | $ 12,300,000 | $ 16,200,000 |
Additional consideration due to the seller |  | $ 5,000,000 |  | $ 28,600,000 |  |  |
Wireline Network Holdings LLC | IP Transit Services Agreement | Buyer |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Estimated payment related to acquired short-term lease obligations | $ 28,100,000 |  | $ 17,000,000 |  |  |  |
Estimated payment related to acquired short-term lease obligations, number of equal payments | installment | 4 |  |  |  |  |  |
Estimated Purchase Agreement payment to be received, amount of discount | $ 8,400,000 |  |  |  |  |  |
Minimum |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
On-net service speed range | MB |  |  |  |  | 100 |  |
Minimum | Wireline Network Holdings LLC | Purchase Agreement | Buyer |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Estimated payment related to acquired short-term lease obligations, payment period after closing date | 55 months |  |  |  |  |  |
Minimum | Wireline Network Holdings LLC | IP Transit Services Agreement | Buyer |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Estimated payment related to acquired short-term lease obligations, payment period after closing date | 55 days |  |  |  |  |  |
Maximum |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
On-net service speed range | GB |  |  |  |  | 400 |  |
Maximum | Wireline Network Holdings LLC | Purchase Agreement | Buyer |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Estimated payment related to acquired short-term lease obligations, payment period after closing date | 58 months |  |  |  |  |  |
Maximum | Wireline Network Holdings LLC | IP Transit Services Agreement | Buyer |  |  |  |  |  |  |
Description of the business: |  |  |  |  |  |  |
Estimated payment related to acquired short-term lease obligations, payment period after closing date | 58 days |  |  |  |  |  |

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