Goodwill and Intangible Assets

Intangible assets as of December 31, 2018 and 2017, were as follows:



	Total			Electronics Segment			Brake Systems Segment
Goodwill
Carrying amount at January 1, 2017	$	490		$	278		$	212
Acquisition	30			13			17
Goodwill impairment charge	(234		)	—			(234		)
Translation differences	6			—			5
Carrying amount at December 31, 2017	292			292			—
Translation differences	(1		)	(1		)	—
Carrying amount at December 31, 2018	$	291		$	291		$	—

Of the $30 million of goodwill recognized as of December 31, 2017, $13 million is related to the Fotonic acquisition in the fourth quarter of 2017 and $17 million is related to the finalization of the purchase price allocation for Brake Systems acquisition in the first quarter of 2017 (see Note 4, Business Combinations). During the year ended December 31, 2017, the Company recognized an impairment charge of the full goodwill amount of $234 million, after consideration of foreign exchange movements, related to Brake Systems. The Company estimated the fair value of Brake Systems using the discounted cash flow method, taking into account expected long-term operating cash-flow performance. The primary driver of the goodwill impairment was due to the lower expected long-term operating cash flow performance of the business unit as of the measurement date. For more information regarding the Company’s impairment testing, see section “Goodwill and Intangible Assets” in Note 2, Summary of Significant Accounting Policies.



	As of December 31
Amortizable Intangible	2018			2017
Gross carrying amount	$	260		$	249
Acquisition	3			4
Translation differences	1			7
Accumulated amortization	(161		)	(138		)
Carrying value	$	102		$	122

During the year ended December 31, 2017 the Company received information related to a contract with an OEM customer of MACOM products and as a result the Company recognized an impairment charge to amortization of intangibles in the Consolidated Statements of Operations for a customer contract of $12 million.

Of the carrying value of $102 million as of December 31, 2018, $71 million was related to the technology asset category and $31 million was related to the contractual relationships' asset category. Of the carrying value of $122 million at December 31, 2017, $80 million was related to the technology asset category and $38 million was related to the contractual relationships' asset category.

The Company recorded approximately $23 million, $37 million and $35 million of amortization expense related to definite-lived intangible assets for the years ended December 31, 2018, 2017 and 2016, respectively. The Company currently estimated future amortization expense be $22 million for 2019, $21 million for 2020, $19 million for 2021, $17 million for 2022 and $8 million for 2023. Indefinite-lived intangible assets are not amortized but are tested for impairment at least annually, or earlier when events and circumstances indicate that it is more likely than not that such assets have been impaired.