The following table summarizes the activity of costs of obtaining contracts with customers: | | | | | | | | | | | | | | | Three months ended | | Six months ended | | | June 30, | | June 30, | | | 2025 | | 2024 | | 2025 | | 2024 | | | | (in millions) | Balance at beginning of period | | $ | 42.1 | | $ | 42.9 | | $ | 42.6 | | $ | 42.4 | Deferral | | | 4.3 | | | 4.5 | | | 8.0 | | | 9.2 | Amortization | | | (4.3) | | | (4.2) | | | (8.5) | | | (8.4) | Balance at end of period | | $ | 42.1 | | $ | 43.2 | | $ | 42.1 | | $ | 43.2 |
The following table presents the current and non-current portion of costs of obtaining contracts with customers as of the end of the corresponding periods: | | | | | | | | | June 30, 2025 | | December 31, 2024 | | | | (in millions) | Current costs of obtaining contracts with customers | | $ | 16.9 | | $ | 16.8 | Non-current costs of obtaining contracts with customers | | | 25.2 | | | 25.8 | Total costs of obtaining contracts with customers | | $ | 42.1 | | $ | 42.6 |
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