(6) Goodwill and Intangible Assets

Goodwill and Indefinite Lived Assets

Changes in the carrying amount of goodwill are as follows:

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As presented in the accompanying consolidated balance sheets, cable certificates are the majority of the other significant indefinite lived intangible assets.

Intangible Assets Subject to Amortization, net

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Intangible assets are being amortized generally on an accelerated basis as reflected in amortization expense and in the future amortization table below.

Amortization expense for intangible assets with finite useful lives was $64 million, $67 million and $75 million for the years ended December 31, 2023, 2022 and 2021, respectively. Amortization expense for amortizable intangible assets for each of the five succeeding fiscal years is estimated to be (amounts in millions):

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