Summary of Significant Accounting Policies (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Summary of significant accounting policies (Textual) [Abstract]
Oncology practice combined represented revenue	15.30%	9.90%	16.60%	6.00%
Revenue of all other clients individually			less than 5%