Patents and other intangible assets

12 Months Ended

Dec. 31, 2011

Patents and other intangible assets

Patents and other intangible assets

4.Patents and other intangible assets

	December 31,
(US$ in thousands)	2011			2010
Cost
Patents and developed technologies	$	29,065		$	26,226
Trademarks—definite lived (subject to amortization)	646			543
Trademarks—indefinite lived (not subject to amortization)	23,057			23,104
Distribution networks	44,586			44,586
	97,354			94,459
Accumulated amortization
Patents and developed technologies	(22,073		)	(18,267		)
Trademarks—definite lived (subject to amortization)	(416		)	(337		)
Distribution networks	(37,350		)	(34,398		)
Patents and other intangible assets, net	$	37,515		$	41,457

Amortization expense for intangible assets is estimated to be approximately $5.1 million, $4.5 million, $1.5 million, $1.4 million, $0.9 million and $1.1 million for the periods ending December 31, 2012, 2013, 2014, 2015, 2016 and 2017 and thereafter, respectively.