Goodwill and Other Intangible Assets (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Intangible Assets, by category
Gross Carrying Amount	$ 213,517		$ 196,695
Accumulated Amortization	145,678		143,434
Amortization expense for intangible assets	2,553	3,948
Estimated amortization expense for next 5 years
2014	10,000
2015	8,500
2016	8,000
2017	5,000
2018	4,750
Customer related
Intangible Assets, by category
Gross Carrying Amount	163,901		150,307
Accumulated Amortization	112,318		110,889
Non-compete agreements
Intangible Assets, by category
Gross Carrying Amount	1,126		1,126
Accumulated Amortization	1,032		1,024
Patents
Intangible Assets, by category
Gross Carrying Amount	6,237		6,211
Accumulated Amortization	5,344		5,273
Technology related
Intangible Assets, by category
Gross Carrying Amount	26,957		27,185
Accumulated Amortization	19,469		18,931
Trade names
Intangible Assets, by category
Gross Carrying Amount	7,667		4,113
Accumulated Amortization	3,159		2,969
Other
Intangible Assets, by category
Gross Carrying Amount	7,629		7,753
Accumulated Amortization	$ 4,356		$ 4,348