Summary of Significant Accounting Policies (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Summary of Significant Accounting Policies Additional (Textual) [Abstract]
Promissory notes receivable	$ 2,706,000	$ 3,876,000
Product warranty period	From six months to two years
Amount revenue increased due to adoption of updated revenue recognition guidance		3,008,000
Advertising costs	2,157,000	1,402,000	856,000
Accumulated other comprehensive loss consisting of foreign currency translation adjustments, net of tax	16,166,000	7,675,000
Net unrealized gain (loss) on available-for-sale investments, net of tax	84,000	(271,000)
Maximum investment of the company in partnership	less than 5%
Losses on currency swaps, net of gains on long-term intercompany loans, net of tax	$ 1,271,000	$ 1,271,000
Building [Member]
Property Plant And Equipment [Line Items]
Useful lives, Maximum	39
Computer hardware and software [Member]
Property Plant And Equipment [Line Items]
Useful lives, Maximum	5
Useful lives, Minimum	2
Manufacturing test equipment [Member]
Property Plant And Equipment [Line Items]
Useful lives, Maximum	5
Useful lives, Minimum	2
Furniture and Fixtures [Member]
Property Plant And Equipment [Line Items]
Useful lives, Maximum	5
Useful lives, Minimum	2
Building Improvements [Member]
Property Plant And Equipment [Line Items]
Useful lives, Maximum	10
Distribution networks [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Useful Estimated Life, Intangible Assets, Maximum	12
Useful Estimated Life, Intangible Assets, Minimum	11
Customer contracts and relationships [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Useful Estimated Life, Intangible Assets, Maximum	12
Useful Estimated Life, Intangible Assets, Minimum	8
Completed Technologies and Other Intangible Assets [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Useful Estimated Life, Intangible Assets, Maximum	8
Useful Estimated Life, Intangible Assets, Minimum	3