Summary of Significant Accounting Policies (Details 4) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Other Intangible Assets
Gross Carrying Amount	$ 150,427	$ 129,075
Accumulated Amortization	(55,604)	(36,672)
Other intangible assets, net	94,823	92,403
Customer Relationships [Member]
Other Intangible Assets
Gross Carrying Amount	110,404	82,891
Accumulated Amortization	(36,605)	(21,147)
Other intangible assets, net	73,799	61,744
Non Compete Agreements [Member]
Other Intangible Assets
Gross Carrying Amount	12,707	13,035
Accumulated Amortization	(7,357)	(8,067)
Other intangible assets, net	5,350	4,968
Favorable lease asset [Member]
Other Intangible Assets
Gross Carrying Amount	7,228	5,571
Accumulated Amortization	(3,866)	(3,210)
Other intangible assets, net	3,362	2,361
Technology [Member]
Other Intangible Assets
Gross Carrying Amount	6,588	16,589
Accumulated Amortization	(4,179)	(2,342)
Other intangible assets, net	2,409	14,247
Trademarks [Member]
Other Intangible Assets
Gross Carrying Amount	12,494	7,405
Accumulated Amortization	(3,001)	(1,686)
Other intangible assets, net	9,493	5,719
Contracts [Member]
Other Intangible Assets
Gross Carrying Amount	956	3,500
Accumulated Amortization	(570)	(185)
Other intangible assets, net	386	3,315
Client lists [Member]
Other Intangible Assets
Gross Carrying Amount	50	84
Accumulated Amortization	(26)	(35)
Other intangible assets, net	$ 24	$ 49