Intangible Assets

3 Months Ended

Mar. 31, 2019

Goodwill And Intangible Assets Disclosure [Abstract]

Intangible Assets

5. Intangible Assets, net

Intangible assets are related to certain capitalized milestone and sublicense payments. The following table presents intangible assets (in thousands):

	March 31, 2019			December 31, 2018
Intangible assets	$	19,773		$	19,773
Less accumulated amortization		(10,328	)		(8,056	)
Total	$	9,445		$	11,717

We recorded $2.3 million and $2.4 million as cost of sales - amortization of intangible assets for the three months ended March 31, 2019 and 2018, respectively. See Note 7.