Other Intangible Assets, Net (Schedule of Finite-Lived Intangible Assets by Major Class) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Other intangible assets, gross	$ 322,648,000		$ 322,648,000		$ 323,281,000
Less accumulated amortization	(166,924,000)		(166,924,000)		(151,697,000)
Total	155,724,000		155,724,000		171,584,000
Amortization expense for finite-lived intangible assets	8,700,000	6,700,000	17,200,000	13,400,000
Customer Lists [Member]
Finite-Lived Intangible Assets [Line Items]
Other intangible assets, gross	283,675,000		283,675,000		286,164,000
Less accumulated amortization	(151,266,000)		(151,266,000)		(137,782,000)
Total	132,409,000		132,409,000		148,382,000
Noncompete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Other intangible assets, gross	9,152,000		9,152,000		9,264,000
Less accumulated amortization	(5,998,000)		(5,998,000)		(5,438,000)
Total	3,154,000		3,154,000		3,826,000
Trade Names and Licenses [Member]
Finite-Lived Intangible Assets [Line Items]
Other intangible assets, gross	29,821,000		29,821,000		27,853,000
Less accumulated amortization	(9,660,000)		(9,660,000)		(8,477,000)
Total	$ 20,161,000		$ 20,161,000		$ 19,376,000