Goodwill and Intangible Assets (Summary of Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 25,665	$ 25,565
Accumulated Amortization	(13,535)	(12,477)
Net Carrying Amount	12,130	13,088
Technology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	18,533	18,533
Accumulated Amortization	(8,547)	(7,678)
Net Carrying Amount	9,986	10,855
Weighted Average Amortization Period	3 years 9 months 18 days	3 years 9 months 18 days
Customer relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	5,061	5,061
Accumulated Amortization	(3,314)	(3,148)
Net Carrying Amount	1,747	1,913
Weighted Average Amortization Period	3 years 6 months	3 years 6 months
Trade names [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	725	725
Accumulated Amortization	(725)	(725)
Net Carrying Amount	0	0
Weighted Average Amortization Period	2 years 8 months 12 days	2 years 8 months 12 days
Non-compete agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	586	486
Accumulated Amortization	(494)	(486)
Net Carrying Amount	92	0
Weighted Average Amortization Period	1 year 2 months 12 days	1 year 2 months 12 days
Patents [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	475	475
Accumulated Amortization	(200)	(189)
Net Carrying Amount	275	286
Weighted Average Amortization Period	11 years	11 years
Other [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	285	285
Accumulated Amortization	(255)	(251)
Net Carrying Amount	$ 30	$ 34
Weighted Average Amortization Period	3 years	3 years