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Goodwill and Related Intangible Assets (Tables) | 9 Months Ended
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Sep. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract] |
Schedule Of Changes In Carrying Amount Of Goodwill | The changes in the carrying amount of goodwill for the nine months ended September 30, 2018 are as follows (in thousands):
| Residential Products |  | Industrial and Infrastructure Products |  | Renewable Energy & Conservation |  | Total
Balance at December 31, 2017 | $ | 198,075 |  |  | $ | 54,280 |  |  | $ | 68,719 |  |  | $ | 321,074 |
Acquired goodwill | — |  |  | — |  |  | 2,838 |  |  | 2,838 |
Adjustments to prior year acquisitions | — |  |  | (38 | ) |  | — |  |  | (38 | )
Foreign currency translation | — |  |  | (165 | ) |  | (388 | ) |  | (553 | )
Balance at September 30, 2018 | $ | 198,075 |  |  | $ | 54,077 |  |  | $ | 71,169 |  |  | $ | 323,321 |
Schedule Of Acquired Intangible Assets | Acquired intangible assets consist of the following (in thousands):
| September 30, 2018 |  | December 31, 2017 |  |
| Gross Carrying Amount |  | Accumulated Amortization |  | Gross Carrying Amount |  | Accumulated Amortization |  | Estimated Life
Indefinite-lived intangible assets: |  |  |  |  |  |  |  |  |
Trademarks | $ | 45,096 |  |  | $ | — |  |  | $ | 45,107 |  |  | $ | — |  |  | Indefinite
Finite-lived intangible assets: |  |  |  |  |  |  |  |  |
Trademarks | 6,148 |  |  | 3,397 |  |  | 5,876 |  |  | 3,062 |  |  | 3 to 15 Years
Unpatented technology | 28,644 |  |  | 13,406 |  |  | 28,107 |  |  | 12,033 |  |  | 5 to 20 Years
Customer relationships | 70,593 |  |  | 34,626 |  |  | 80,707 |  |  | 39,652 |  |  | 5 to 17 Years
Non-compete agreements | 1,649 |  |  | 1,156 |  |  | 1,649 |  |  | 931 |  |  | 4 to 10 Years
| 107,034 |  |  | 52,585 |  |  | 116,339 |  |  | 55,678 |  |  |
Total acquired intangible assets | $ | 152,130 |  |  | $ | 52,585 |  |  | $ | 161,446 |  |  | $ | 55,678 |  |  |
Schedule of Acquired Intangible Asset Amortization Expense | The following table summarizes the acquired intangible asset amortization expense for the three and nine months ended September 30 (in thousands):
| Three Months Ended September 30, |  | Nine Months Ended September 30,
| 2018 |  | 2017 |  | 2018 |  | 2017
Amortization expense | $ | 2,121 |  |  | $ | 2,208 |  |  | $ | 6,408 |  |  | $ | 6,600 |
Schedule Of Amortization Expense | Amortization expense related to acquired intangible assets for the remainder of fiscal 2018 and the next five years thereafter is estimated as follows (in thousands):
| 2018 |  | 2019 |  | 2020 |  | 2021 |  | 2022 |  | 2023
Amortization expense | $ | 1,960 |  |  | $ | 7,841 |  |  | $ | 7,329 |  |  | $ | 6,726 |  |  | $ | 6,315 |  |  | $ | 5,776 |

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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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