Summary of Significant Accounting Policies (Details 2)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Percentage of net service revenue
Percentage of net service revenue	100.00%	100.00%	100.00%
Home Based Services [Member]
Percentage of net service revenue
Percentage of net service revenue	88.40%	88.00%	87.90%
Facility Based Services [Member]
Percentage of net service revenue
Percentage of net service revenue	11.60%	12.00%	12.10%