Goodwill and Intangible AssetsChanges to goodwill are as follows: | | | | | | | | | | | | | (in millions) | SAT | DTT | Total | Balance as of December 31, 2025 | $ | 539.8 | | $ | 624.2 | | $ | 1,164.0 | | | Additions (see Note 2) | — | | 277.1 | | 277.1 | | | Currency translation and other | 0.8 | | (5.9) | | (5.1) | | | | | | Balance as of June 30, 2026 | $ | 540.6 | | $ | 895.4 | | $ | 1,436.0 | |
Changes to intangible assets are as follows: | | | | | | | | | | | | | (in millions) | Six Months Ended June 30, 2026 | | Year Ended December 31, 2025 | | Balance at beginning of period, net of accumulated amortization | $ | 557.2 | | | $ | 419.3 | | | Additions (see Note 2) | 233.5 | | | 191.1 | | | | | | | Amortization expense | (41.0) | | | (59.5) | | | Currency translation and other | (4.0) | | | 6.3 | | Balance at end of period, net of accumulated amortization1 | $ | 745.7 | | | $ | 557.2 | | 1 Includes $45.5 million intangibles with indefinite useful lives. | | | | | | | | |
A summary of intangible assets are as follows: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Weighted Average Amortization Period of Finite Lived Assets (in years) | | June 30, 2026 | | December 31, 2025 | | (in millions) | | Gross Asset | | Accumulated Amortization | | Net | | Gross Asset | | Accumulated Amortization | | Net | | Customer relationships and backlog | 18.0 | | $ | 928.8 | | | $ | 364.1 | | | $ | 564.7 | | | $ | 767.9 | | | $ | 339.2 | | | $ | 428.7 | | | Intellectual property rights | 6.1 | | 83.1 | | | 19.3 | | | 63.8 | | | 66.0 | | | 18.4 | | | 47.6 | | | Developed Technology | 6.0 | | 161.2 | | | 52.2 | | | 109.0 | | | 113.2 | | | 42.2 | | | 71.0 | | | Other | 12.2 | | 74.1 | | | 65.9 | | | 8.2 | | | 75.0 | | | 65.1 | | | 9.9 | | | Total | 17.4 | | $ | 1,247.2 | | | $ | 501.5 | | | $ | 745.7 | | | $ | 1,022.1 | | | $ | 464.9 | | | $ | 557.2 | | Future amortization expense associated with intangible assets is expected to be: | | | | | | | (in millions) | | | Remainder of 2026 | $ | 51.1 | | | 2027 | $ | 91.3 | | | 2028 | $ | 83.2 | | | 2029 | $ | 80.5 | | | 2030 | $ | 56.5 | | | 2031 and after | $ | 337.6 | |
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