9. Intangibles

Intangible assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable.

Amortization of capitalized patent costs associated with the application and award of patents in the U.S. and various other countries are capitalized and amortized on a straight-line basis over the term of the patents as determined at the award date, which varies depending on the pendency period of the application, generally approximating seventeen years.

Amortization of intangible assets acquired is calculated using the straight-line method over the estimated useful lives of the assets.

	June 30, 2016			December 31, 2015
Capitalized patent costs	$	6,971		$	6,779
Intangible assets acquired:
Purchased patents and intellectual property		250			250
Existing technology		1,560			1,560
Customer relationships		290			290
Backlog		760			760
Tradenames		290			290
Non-solicitation agreements		120			120
Gross intangible assets		10,241			10,049
Accumulated amortization		(3,772	)		(3,436	)
Intangibles, net	$	6,469		$	6,613