Patents and other intangible assets

6 Months Ended

Jun. 30, 2014

Goodwill and Intangible Assets Disclosure [Abstract]

Patents and other intangible assets

4. Patents and other intangible assets

(U.S. Dollars, in thousands)	June 30, 2014			December 31, 2013
Cost
Patents	$	35,526		$	34,820
Trademarks — definite lived		659			620
Licenses and other		7,248			7,748
		43,433			43,188
Accumulated amortization
Patents		(32,772	)		(31,739	)
Trademarks — definite lived		(509	)		(454	)
Licenses and other		(2,077	)		(1,949	)
		(35,358	)		(34,142	)
Patents and other intangible assets, net	$	8,075		$	9,046