INTANGIBLE ASSETS AND OTHER ASSETS

During the year ended December 31, 2016, we recorded impairment charges of $0.3 million related to our patents.

In 2015, we performed an impairment test as of September 30, 2015 due to the significant decline in the market price of our stock. As a result of this testing, we recorded impairment charges related to our long-lived assets of approximately $7.0 million during the three months ended September 30, 2015. The impairment charges included $0.8 million related to property and equipment and $6.2 million related to amortizable intangibles.

Long-lived intangible assets and other assets consisted of the following:



	Dollars in Thousands
	December 31, 2016
	Cost		Accumulated Amortization		Net Book Value
Patents	$	233	$	26	$	207
Intellectual property	672		317		355
	$	905	$	343	$	562



	Dollars in Thousands
	December 31, 2015
	Cost		Accumulated Amortization		Net Book Value
Patents	$	773	$	67	$	706
Intellectual property	671		207		464
	$	1,444	$	274	$	1,170




	Estimated Useful Life
Patents	13.5 years
Intellectual property	7 years

During the year ended December 31, 2016, we impaired patents having a carrying value of $0.3 million. This cost is included in our research and development expense in our accompanying consolidated statements of operations. Also during 2016, we assigned and sold certain patents having a carrying value of $0.2 million. This cost is included in our loss on sale/disposal of assets in our accompanying consolidated statements of operations.

Amortization expense for intangible assets was $0.2 million and $0.1 million during the years ended December 31, 2016 and 2015, respectively. Amortization expense for intangible assets for each of the five succeeding fiscal years is expected to be $0.1 million, $0.1 million, $0.1 million, less than $0.1 million and less than $0.1 million for the years ended December 31, 2017, 2018, 2019, 2020 and 2021, respectively.

Other assets include security deposits.