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Income taxes - Temporary differences (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Deferred Tax Assets: |  |
Net operating loss carry-forwards | $ 236,346 | $ 244,306
Interest expense limitation | 66,386 | 34,828
Accrued liabilities and other | 8,584 | 12,055
Operating leases | 98,261 | 107,563
Total gross deferred tax assets | 409,577 | 398,752
Valuation allowance | (131,773) | (136,533)
Net deferred tax assets | 277,804 | 262,219
Deferred Tax Liabilities: |  |
Property & equipment | 308,254 | 295,630
Intangibles | 113,596 | 118,727
Deferred consideration - IP Transit Services Agreement | 63,070 | 114,844
Investment in foreign subsidiaries | 95,974 | 100,081
Right-of-use assets | 95,176 | 104,435
Gross deferred tax liabilities | 676,070 | 733,717
Net deferred tax liabilities | 398,266 | $ 471,498
Sprint Business |  |
Deferred Tax Liabilities: |  |
Net deferred tax liabilities | $ 475,000 |

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