Goodwill and Other Intangible Assets

Goodwill —The change in the carrying amount of goodwill in 2018 was due to the acquisition of a 55% interest in TM4 and currency fluctuation. The change in the carrying amount of goodwill in 2017 was primarily due to the acquisitions of USM – Warren and 80% interests in BFP and BPT and currency fluctuation. See Note 2 for additional information on recent acquisitions. Based on our October 31, 2018 impairment assessment, the fair value of our reporting units are higher than their carrying values, indicating no impairment.

Changes in the carrying amount of goodwill by segment —



	Light Vehicle		Commercial Vehicle			Off-Highway			Power Technologies		Total
Balance, December 31, 2016	$	—	$	6		$	78		$	6	$	90
Acquisitions	3					20					23
Purchase accounting adjustments			1								1
Currency impact			1			12					13
Balance, December 31, 2017	3		8			110			6		127
Acquisition			148								148
Currency impact			(6		)	(5		)			(11		)
Balance, December 31, 2018	$	3	$	150		$	105		$	6	$	264

Non-amortizable intangible assets — Our non-amortizable intangible assets include trademarks and trade names. Trademarks and trade names consist of the Dana^®, Spicer^® and TM4^® trademarks and trade names utilized in our Commercial Vehicle and Off-Highway segments. We value trademarks and trade names using a relief from royalty method which is based on revenue streams. No impairment was recorded during the three years ended December 31, 2018 in connection with the required annual assessment for trademarks and trade names.

During the third quarter of 2012, we entered a strategic alliance with Fallbrook Technologies Inc. (Fallbrook). The transaction with Fallbrook was accounted for as a business combination and the original purchase price allocation included $20 of intangible assets used in research and development activities, which had been classified as indefinite-lived. Since the third quarter of 2012, we have been working with several customers to commercialize the continuously variable planetary (CVP) technology primarily in combustion engine applications. During the second quarter of 2018 key customers notified us of their intention to redirect their development efforts to electrification and cease further development efforts of the CVP technology in combustion engine applications. While we have not abandoned the CVP technology, we determined that it was more likely than not that the fair value of the related intangible assets was less than their carrying amount. We used the multi-period excess earnings method, an income approach, to fair value the assets used in research and development activities. Given the lack of adequate identifiable future revenue streams, it was determined that the $20 of intangible assets used in research and development activities was fully impaired during the second quarter of 2018.

Amortizable intangible assets — Our amortizable intangible assets include core technology, customer relationships and a portion of our trademarks and trade names. Trademarks and trade names includes the Brevini^® trademark and trade name utilized in our Off-Highway segment. Core technology includes the proprietary know-how and expertise that is inherent in our products and manufacturing processes. Customer relationships include the established relationships with our customers and the related ability of these customers to continue to generate future recurring revenue and income.

These assets are tested for impairment whenever events or changes in circumstances indicate that their carrying amounts may not be recoverable. We group the assets and liabilities at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities and evaluate the asset group against the undiscounted future cash flows. We use our internal forecasts, which we update quarterly, to develop our cash flow projections. These forecasts are based on our knowledge of our customers’ production forecasts, our assessment of market growth rates, net new business, material and labor cost estimates, cost recovery agreements with customers and our estimate of savings expected from our restructuring activities. The most likely factors that would significantly impact our forecasts are changes in customer production levels and loss of significant portions of our business. Our valuation is applied over the life of the primary assets within the asset groups. If the undiscounted cash flows do not indicate that the carrying amount of the asset group is recoverable, an impairment charge is recorded if the carrying amount of the asset group exceeds its fair value based on discounted cash flow analyses or appraisals. There were no impairments recorded during the three years ended December 31, 2018.

Components of other intangible assets —



		December 31, 2018							December 31, 2017
	Weighted Average Useful Life (years)	Gross Carrying Amount		Accumulated Impairment and Amortization			Net Carrying Amount		Gross Carrying Amount		Accumulated Impairment and Amortization			Net Carrying Amount
Amortizable intangible assets
Core technology	8	$	107	$	(89	)	$	18	$	95	$	(88	)	$	7
Trademarks and trade names	16	16		(4		)	12		17		(2		)	15
Customer relationships	8	460		(400		)	60		470		(403		)	67
Non-amortizable intangible assets
Trademarks and trade names		74					74		65					65
Used in research and development activities		20		(20		)	—		20					20
		$	677	$	(513	)	$	164	$	667	$	(493	)	$	174

The net carrying amounts of intangible assets, other than goodwill, attributable to each of our operating segments at December 31, 2018 were as follows: Light Vehicle Driveline (Light Vehicle) – $28, Commercial Vehicle – $54, Off-Highway – $73 and Power Technologies – $9.

Amortization expense related to amortizable intangible assets —



	2018		2017		2016
Charged to cost of sales	$	2	$	2	$	1
Charged to amortization of intangibles	8		11		8
Total amortization	$	10	$	13	$	9

The following table provides the estimated aggregate pre-tax amortization expense related to intangible assets for each of the next five years based on December 31, 2018 exchange rates. Actual amounts may differ from these estimates due to such factors as currency translation, customer turnover, impairments, additional intangible asset acquisitions and other events.



	2019		2020		2021		2022		2023
Amortization expense	$	9	$	8	$	8	$	8	$	8