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Goodwill and Related Intangible Assets (Tables) | 3 Months Ended
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Mar. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract] |
Schedule Of Changes In Carrying Amount Of Goodwill | The changes in the carrying amount of goodwill for the three months ended March 31, 2020 are as follows (in thousands):
| Renewable Energy & Conservation |  | Residential Products |  | Industrial and Infrastructure Products |  | Total
Balance at December 31, 2019 | $ | 77,602 |  |  | $ | 198,075 |  |  | $ | 54,028 |  |  | $ | 329,705 |
Acquired goodwill | 52,659 |  |  | — |  |  | — |  |  | 52,659 |
Adjustments to prior year acquisitions | 75 |  |  | — |  |  | — |  |  | 75 |
Foreign currency translation | 75 |  |  | — |  |  | (469 | ) |  | (394 | )
Balance at March 31, 2020 | $ | 130,411 |  |  | $ | 198,075 |  |  | $ | 53,559 |  |  | $ | 382,045 |
Schedule Of Acquired Intangible Assets | Acquired intangible assets consist of the following (in thousands):
| March 31, 2020 |  | December 31, 2019 |  |
| Gross Carrying Amount |  | Accumulated Amortization |  | Gross Carrying Amount |  | Accumulated Amortization |  | Weighted-Average Amortization Period
Indefinite-lived intangible assets: |  |  |  |  |  |  |  |  |
Trademarks | $ | 45,770 |  |  | $ | — |  |  | $ | 45,770 |  |  | $ | — |  |  | Indefinite
Finite-lived intangible assets: |  |  |  |  |  |  |  |  |
Trademarks | 8,693 |  |  | 4,239 |  |  | 6,139 |  |  | 4,105 |  |  | 3 to 15 Years
Unpatented technology | 34,289 |  |  | 16,354 |  |  | 29,544 |  |  | 15,807 |  |  | 5 to 20 Years
Customer relationships | 80,777 |  |  | 41,490 |  |  | 71,195 |  |  | 40,294 |  |  | 5 to 17 Years
Non-compete agreements | 1,649 |  |  | 1,567 |  |  | 1,649 |  |  | 1,499 |  |  | 4 to 10 Years
| 125,408 |  |  | 63,650 |  |  | 108,527 |  |  | 61,705 |  |  |
Total acquired intangible assets | $ | 171,178 |  |  | $ | 63,650 |  |  | $ | 154,297 |  |  | $ | 61,705 |  |  |
Schedule of Acquired Intangible Asset Amortization Expense | The following table summarizes the acquired intangible asset amortization expense for the three months ended March 31 (in thousands):
|  | Three Months Ended March 31,
|  | 2020 |  | 2019
Amortization expense |  | $ | 2,078 |  |  | $ | 1,797 |
Schedule Of Amortization Expense | Amortization expense related to acquired intangible assets for the remainder of fiscal 2020 and the next five years thereafter is estimated as follows (in thousands):
| 2020 |  | 2021 |  | 2022 |  | 2023 |  | 2024 |  | 2025
Amortization expense | $ | 5,311 |  |  | $ | 6,937 |  |  | $ | 6,459 |  |  | $ | 5,921 |  |  | $ | 5,666 |  |  | $ | 5,566 |

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- Definition Tabular disclosure of the characteristics, including initial carrying value, residual amount, weighted average useful life, of finite-lived intangible assets acquired during the period by major class. A major class is composed of intangible assets that can be grouped together because they are similar, either by nature or by their use in the operations of the company. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
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