Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Intangible assets
Intangible assets, net	$ 145,075	$ 150,572
Intangible assets subject to amortization
Intangible assets	122,235	128,332
Developed technology [Member]
Intangible assets subject to amortization
Intangible assets	51,672	51,159
Customer relationships [Member]
Intangible assets subject to amortization
Intangible assets	57,117	61,609
In-process research and development [Member]
Intangible assets subject to amortization
Intangible assets	9,986	10,057
Other intangible assets [Member]
Intangible assets subject to amortization
Intangible assets	3,460	5,507
Trademarks and trade names [Member]
Intangible assets not subject to amortization
Intangible assets	$ 22,840	$ 22,240