Goodwill and Intangible Assets (Summary of Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 50,348	$ 50,187
Accumulated Amortization	(19,719)		(17,567)
Intangibles, net	30,629		32,620
Technology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	28,005	27,844
Accumulated Amortization	(12,379)		(11,303)
Intangibles, net	15,626		16,541
Weighted Average Amortization Period	5 years 3 months 18 days		5 years 3 months 18 days
Customer relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	16,008	16,008
Accumulated Amortization	(4,818)		(4,055)
Intangibles, net	11,190		11,953
Weighted Average Amortization Period	7 years 10 months 18 days		7 years 10 months 18 days
Trade names [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,287	1,287
Accumulated Amortization	(946)		(817)
Intangibles, net	341		470
Weighted Average Amortization Period	2 years 9 months 12 days		2 years 9 months 12 days
Non-compete agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,446	1,446
Accumulated Amortization	(721)		(625)
Intangibles, net	725		821
Weighted Average Amortization Period	2 years 3 months 12 days		2 years 3 months 12 days
Patents [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,290	3,290
Accumulated Amortization	(584)		(500)
Intangibles, net	2,706		2,790
Weighted Average Amortization Period	9 years 10 months 18 days		9 years 10 months 18 days
Other [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	312	312
Accumulated Amortization	(271)		(267)
Intangibles, net	$ 41		$ 45
Weighted Average Amortization Period	3 years		3 years