Goodwill and Intangible Assets Intangibles (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 130,382	$ 131,107
Accumulated Amortization	64,414	61,618
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	117,141	117,794
Accumulated Amortization	57,579	55,157
Non-compete agreements
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,888	3,888
Accumulated Amortization	3,652	3,569
Trade name
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	7,953	8,025
Accumulated Amortization	2,114	1,939
Developed technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,400	1,400
Accumulated Amortization	$ 1,069	$ 953