Intangibles (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Finite-Lived Intangible Assets [Line Items]
Total intangible assets amortization expenses	$ 7,500,000	$ 5,200,000
Capitalized Software Development Costs [Member]
Finite-Lived Intangible Assets [Line Items]
Capitalized software development costs	3,900,000	3,900,000
Capitalized computer software amortization	3,600,000	3,200,000
Costs related to stock based compensation	$ 178,000	$ 149,000
Useful life (in years)	3 years
Minimum [Member] | Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	10 years
Minimum [Member] | Other Assets [Member] | Acquired Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	3 years
Maximum [Member] | Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	17 years
Maximum [Member] | Other Assets [Member] | Acquired Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	8 years