Goodwill and Intangible Assets (Details 1) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Summary of company's intangible assets
Cost	$ 20,525	$ 9,390
Accumulated Amortization	(8,482)	(8,040)
Net Carrying Amount	12,043	1,350
Technology [Member]
Summary of company's intangible assets
Cost	9,010	4,010
Accumulated Amortization	(4,114)	(3,892)
Net Carrying Amount	4,896	118
Customer relationships [Member]
Summary of company's intangible assets
Cost	8,985	3,530
Accumulated Amortization	(2,499)	(2,364)
Net Carrying Amount	6,486	1,166
Non-competition agreements [Member]
Summary of company's intangible assets
Cost	1,640	1,260
Accumulated Amortization	(1,271)	(1,214)
Net Carrying Amount	369	46
Tradenames [Member]
Summary of company's intangible assets
Cost	890	590
Accumulated Amortization	(598)	(570)
Net Carrying Amount	$ 292	$ 20