Summary of Significant Accounting Policies (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Concentration of Business
Net revenue	$ 1,008,210	$ 873,598	$ 842,748	$ 821,761	$ 830,274	$ 798,437	$ 805,473	$ 773,213	$ 3,546,317	$ 3,207,397	$ 2,799,400
Minimum
Concentration of Business
Term of Contract									1 year
Term of renewed contract									1 year
Notice period for termination of contract									60 days
Maximum
Concentration of Business
Term of Contract									3 years
Term of renewed contract									2 years
Notice period for termination of contract									180 days
Pennsylvania Counties
Concentration of Business
Net revenue									359,000	354,100	351,600
Florida Areas
Concentration of Business
Net revenue									$ 128,000	$ 133,900	$ 131,800