(4) Goodwill and Other Intangible Assets

Goodwill and Indefinite Lived Intangible Assets

Changes in the carrying amount of goodwill are as follows:

​

As presented in the accompanying consolidated balance sheets, trademarks are the other significant indefinite lived intangible asset. See the disclosure below for information related to the 2020 impairment of the Company’s trademarks. Other fluctuations in the trademark balance from the prior year were due to the change in foreign exchange rates.

​

Intangible Assets Subject to Amortization

Intangible assets subject to amortization are comprised of the following:

​

​

Amortization expense was $74 million, $122 million and $136 million for the years ended December 31, 2022, 2021 and 2020, respectively.

Intangible assets are generally amortized on a straight-line basis. The estimated future amortization expense for the next five years related to intangible assets with definite lives as of December 31, 2022 is as follows (amounts in millions):

​

Impairments

Due to the impact of COVID-19 on Tripadvisor’s operating results, and a sustained decline in Tripadvisor’s stock price, impairments of $250 million of trademarks and $279 million of goodwill were recorded during the year ended December 31, 2020, respectively, related to the former Hotels, Media & Platform reporting unit, which as of December 31, 2022 is included in the Tripadvisor Core reporting unit. The fair value of the trademarks was determined using the relief from royalty method. The fair value of the reporting unit was determined using a combination of market multiples (market approach) and discounted cash flow (income approach) calculations (Level 3). 

Following the change in reportable segments during the second quarter of 2022, the new reporting units are as follows: (1) Tripadvisor Core, (2) Viator, and (3) TheFork, for the purpose of goodwill impairment testing. As a result of this reporting unit change, we performed a qualitative goodwill impairment assessment of our legacy and current reporting units during the second quarter of 2022 and determined that it was more likely than not that the respective fair values of the legacy and current reporting units were greater than their respective carrying values.

As of December 31, 2022, accumulated goodwill impairment losses for Tripadvisor totaled $1,571 million.