| Goodwill and intangible assets |
9. Goodwill and intangible assets Goodwill The following table sets forth the changes in our goodwill balance, for all periods presented: | | | | | | Goodwill | Balance at December 31, 2018 | | $ | 59,640 | Measurement period adjustments for acquisition of Elauwit | | | (1,061) | Balance at December 31, 2019 | | $ | 58,579 |
Intangible assets The following table sets forth the changes in our intangible assets balance, for all periods presented: | | | | | | Intangible | | | Assets | Balance at December 31, 2018 | | $ | 19,152 | Measurement period adjustments for acquisition of Elauwit | | | (48) | Reclassification of assets held for sale, net | | | 407 | Amortization expense | | | (4,571) | Balance, December 31, 2019 | | | 14,940 | Amortization expense | | | (4,288) | Balance, December 31, 2020 | | $ | 10,652 |
Intangible assets at December 31, 2020 consist of the following: | | | | | | | | | | | | Historical | | Accumulated | | | | | Cost | | Amortization | | Net | Venue contracts | | $ | 19,710 | | $ | (16,030) | | $ | 3,680 | Backlog | | | 7,388 | | | (3,578) | | | 3,810 | Customer and partner relationships | | | 3,780 | | | (962) | | | 2,818 | Non-compete agreements, technology and other | | | 2,134 | | | (1,790) | | | 344 | Total intangible assets | | $ | 33,012 | | $ | (22,360) | | $ | 10,652 |
Intangible assets at December 31, 2019 consist of the following: | | | | | | | | | | | | Historical | | Accumulated | | | | | Cost | | Amortization | | Net | Venue contracts | | $ | 20,431 | | $ | (15,247) | | $ | 5,184 | Backlog | | | 7,388 | | | (2,104) | | | 5,284 | Customer and partner relationships | | | 3,780 | | | (584) | | | 3,196 | Non-compete agreements, technology and other | | | 4,814 | | | (3,538) | | | 1,276 | Total intangible assets | | $ | 36,413 | | $ | (21,473) | | $ | 14,940 |
9. Goodwill and intangible assets (Continued) The decrease in our intangible assets cost and accumulated amortization balances from 2019 to 2020 is primarily related to the write-off of intangible assets that have expired. Amortization expense for fiscal years 2021 through 2025 and thereafter is as follows: | | | | | | Amortization | Year | | Expense | 2021 | | $ | 3,556 | 2022 | | | 3,095 | 2023 | | | 1,901 | 2024 | | | 681 | 2025 | | | 416 | Thereafter | | | 1,003 | | | $ | 10,652 |
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