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Description of the business: - Acquisition of Sprint Communications - Fair Value of Assets Acquired and Liabilities Assumed and Gain on Bargain Purchase (Details) - USD ($) $ in Thousands |  | 3 Months Ended
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May 01, 2023 | Mar. 31, 2025 | Jun. 30, 2024 | Mar. 31, 2024 | Dec. 31, 2023 | Sep. 30, 2023
Gain on bargain purchase |  |  |  |  |  |
Reduction to gain on bargain purchase |  |  |  | $ 5,470 |  |
Adjustment to reclassify, right-of-use leased assets |  |  |  |  |  | $ 24,900
Unfavorable lease liabilities |  |  |  |  |  | $ 160,900
Estimated payment related to acquired short-term lease obligations | $ 157,200 |  |  |  |  |
Optical fiber |  |  |  |  |  |
Current assets: |  |  |  |  |  |
Total property and equipment | 369,200 |  |  |  |  |
Wireline Network Holdings LLC |  |  |  |  |  |
Current assets: |  |  |  |  |  |
Cash and cash equivalents | 47,074 |  |  |  |  |
Accounts receivable | 39,948 |  |  |  |  |
Prepaid expenses and other current assets | 22,777 |  |  |  |  |
Total current assets | 109,799 |  |  |  |  |
Total property and equipment | 965,715 |  |  |  |  |
Right-of-use leased assets | 304,982 |  |  |  |  |
IPv4 intangible assets | 458,000 |  |  |  |  |
Other intangible assets | $ 16,000 |  |  |  |  |
Deposits and other assets | 7,521 |  |  |  |  |
Total assets | $ 1,862,017 |  |  |  |  |
Current liabilities: |  |  |  |  |  |
Accounts payable | 13,313 |  |  |  |  |
Accrued and other current liabilities | $ 25,344 |  |  |  |  |
Current maturities, operating lease liabilities | 74,562 |  |  |  |  |
Current maturities, finance lease liabilities | $ 39,559 |  |  |  |  |
Total current liabilities | 152,778 |  |  |  |  |
Operating lease liabilities, net of current maturities | 251,573 |  |  |  |  |
Finance lease liabilities, net of current maturities | 121,342 |  |  |  |  |
Deferred income tax liabilities | 474,891 |  |  |  |  |
Other long-term liabilities | 35,366 |  |  |  |  |
Total liabilities | 1,035,950 |  |  |  |  |
Fair value of net assets acquired | 826,067 |  |  |  |  |
Gain on bargain purchase |  |  |  |  |  |
Fair value of net assets acquired | 826,067 |  |  |  |  |
Total net consideration to be received from the Seller, net of discounts | 602,581 |  |  |  |  |
Gain on bargain purchase | 1,428,648 | $ 1,400,000 |  |  |  |
Consideration paid | $ 1 | 1 |  |  |  |
Reduction to gain on bargain purchase |  |  | $ 27,700 | 5,500 |  |
Reduction in short term lease payment |  |  |  | 24,200 |  |
Reduction of acquired short term lease obligations, net of discount |  |  |  | 17,000 |  |
Severance reimbursement payments received |  |  | 8,000 | 4,300 |  |
Adjustment to net deferred income tax liabilities |  |  | $ 19,700 |  |  |
Increase in unfavorable lease liabilities |  |  |  | 6,000 |  |
Decrease in accrued liabilities |  |  |  | 11,300 |  |
Reduction in deferred income tax liabilities |  |  |  | 1,900 |  |
Wireline Network Holdings LLC | Customer relationships |  |  |  |  |  |
Current assets: |  |  |  |  |  |
Other intangible assets |  | 16,000 |  |  |  |
Gain on bargain purchase |  |  |  |  |  |
Reduction of intangible assets |  |  |  |  | $ 41,000 |
Acquired customer relationships, estimated useful life (in years) | 9 years |  |  |  |  |
Intangible Assets |  | 400 |  | $ 400 |  |
Acquired customer relationships, future amortization expense per year |  | $ 1,800 |  |  |  |
Acquired customer relationships, future amortization expense, amortization period (in years) |  | 7 years |  |  |  |

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