Acquisitions (Details 1) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2011 Year
D&D Holdings Limited [Member]
Estimated fair values and useful lives of intangible assets acquired
Identifiable intangible assets	$ 25,231
D&D Holdings Limited [Member] | Customer relationships [Member]
Estimated fair values and useful lives of intangible assets acquired
Identifiable intangible assets	19,459
Weighted average useful life	7
D&D Holdings Limited [Member] | Intellectual property [Member]
Estimated fair values and useful lives of intangible assets acquired
Identifiable intangible assets	4,088
Weighted average useful life	8
D&D Holdings Limited [Member] | Non-compete agreements [Member]
Estimated fair values and useful lives of intangible assets acquired
Identifiable intangible assets	1,275
Weighted average useful life	3
D&D Holdings Limited [Member] | Tradename [Member]
Estimated fair values and useful lives of intangible assets acquired
Identifiable intangible assets	409
Weighted average useful life	1.5
Clanmo GmbH [Member]
Estimated fair values and useful lives of intangible assets acquired
Identifiable intangible assets	2,271
Clanmo GmbH [Member] | Customer relationships [Member]
Estimated fair values and useful lives of intangible assets acquired
Identifiable intangible assets	1,447
Weighted average useful life	7
Clanmo GmbH [Member] | Developed technology [Member]
Estimated fair values and useful lives of intangible assets acquired
Identifiable intangible assets	463
Weighted average useful life	8
Clanmo GmbH [Member] | Non-compete agreements [Member]
Estimated fair values and useful lives of intangible assets acquired
Identifiable intangible assets	318
Weighted average useful life	1.5
Clanmo GmbH [Member] | Tradename [Member]
Estimated fair values and useful lives of intangible assets acquired
Identifiable intangible assets	$ 43
Weighted average useful life	5