Goodwill and Intangible Assets

The changes in the carrying amount of goodwill by reportable segment were as follows:



($ in millions)	Proprietary Products			Contract-Manufactured Products			Total
Balance, December 31, 2016	$	73.7		$	29.3		$	103.0
Foreign currency translation	3.9			0.8			4.7
Balance, December 31, 2017	77.6			30.1			107.7
Foreign currency translation	(1.6		)	(0.3		)	(1.9		)
Balance, December 31, 2018	$	76.0		$	29.8		$	105.8

As of December 31, 2018, we had no accumulated goodwill impairment losses.

Intangible assets and accumulated amortization as of December 31 were as follows:



	2018							2017
($ in millions)	Cost		Accumulated Amortization			Net		Cost		Accumulated Amortization			Net
Patents and licensing	$	19.6	$	(15.1	)	$	4.5	$	18.2	$	(14.1	)	$	4.1
Technology	3.3		(1.2		)	2.1		3.3		(1.0		)	2.3
Trademarks	2.0		(1.8		)	0.2		2.0		(1.7		)	0.3
Customer relationships	29.3		(20.0		)	9.3		29.3		(19.1		)	10.2
Customer contracts	11.0		(6.8		)	4.2		11.1		(6.3		)	4.8
	$	65.2	$	(44.9	)	$	20.3	$	63.9	$	(42.2	)	$	21.7

The cost basis of intangible assets includes a foreign currency translation loss of $0.3 million and a foreign currency translation gain of $0.9 million for the years ended December 31, 2018 and 2017, respectively. Amortization expense for the years ended December 31, 2018, 2017 and 2016 was $2.7 million, $2.4 million and $2.6 million, respectively. Estimated annual amortization expense for the next five years is as follows: 2019 - $2.6 million, 2020 - $2.6 million, 2021 - $2.1 million, 2022 - $2.1 million and 2023 - $2.1 million. During 2016, as part of our 2016 restructuring plan, we recorded within other expense a $2.8 million non-cash asset write-down associated with the discontinued use of a patent and a $10.0 million non-cash asset write-down associated with the discontinued use of an indefinite-lived trademark.