v3.19.3.a.u2

INTANGIBLE ASSETS | 12 Months Ended
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Dec. 31, 2019
Intangible Assets, Net (Excluding Goodwill) [Abstract] |
INTANGIBLE ASSETS | INTANGIBLE ASSETS Intangible assets consisted of the following:
| Weighted-Average Amortization Period |  | December 31, 2019 |  | December 31, 2018
|  | Cost |  | Accumulated Amortization |  | Cost |  | Accumulated Amortization
| (Years) |  | (Thousands of Dollars)
Customer contracts and relationships | 18 |  | $ | 863,900 |  |  | $ | (183,832 | ) |  | $ | 863,950 |  |  | $ | (132,509 | )
Other | 47 |  | 2,359 |  |  | (795 | ) |  | 2,359 |  |  | (744 | )
Total |  |  | $ | 866,259 |  |  | $ | (184,627 | ) |  | $ | 866,309 |  |  | $ | (133,253 | )
Intangible assets are recorded at fair value as of the date acquired. All of our intangible assets are amortized on a straight-line basis. Amortization expense for intangible assets was $51.4 million, $51.4 million and $39.6 million for the years ended December 31, 2019, 2018 and 2017, respectively. The estimated aggregate amortization expense is approximately $51.0 million for each of the years 2020 through 2022, and approximately $45.0 million for 2023 and 2024.

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- Definition The entire disclosure for all or part of the information related to intangible assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -URI http://asc.fasb.org/topic&trid=2144416 + Details
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