Notes Payable and Revolving Credit Agreement (Details Textual) (USD $)	9 Months Ended		9 Months Ended
	Sep. 30, 2012 Installment	Mar. 18, 2009	Sep. 30, 2012 Maximum [Member]	Sep. 30, 2012 Minimum [Member]	Sep. 30, 2012 Revolving credit agreement average effective interest rate of 3.7% inclusive of unused fee [Member]	Jun. 04, 2008 Revolving credit agreement average effective interest rate of 3.7% inclusive of unused fee [Member]	Aug. 27, 2007 Revolving credit agreement average effective interest rate of 3.7% inclusive of unused fee [Member]	Sep. 30, 2012 Promissory note payable in annual installments of $100 plus accrued interest through December 31, 2012, interest accrues at 3.25% per annum [Member]	Sep. 30, 2012 Promissory note payable in annual installments of $50 plus accrued interest through December 21, 2012, interest accrues at 4.00% per annum [Member]	Sep. 30, 2012 Promissory note payable in annual installments of $184 plus accrued interest through June 30, 2013, interest accrues at 3.25% per annum [Member]	Sep. 30, 2012 Promissory note payable in annual installments of $100 plus accrued interest through July 25, 2013, interest accrues at 3.25% per annum [Member]	Sep. 30, 2012 Promissory note payable in annual installments of $50 plus accrued interest through January 3, 2014, interest accrues at 3.25% per annum [Member]	Sep. 30, 2012 Promissory notes payable in aggregate annual installments of $125 plus accrued interest through May 22, 2014, interest accrues at 3.25% per annum [Member]
Notes Payable and Revolving Credit Agreement (Textual) [Abstract]
Average effective interest rate					3.70%
Annual installments								$ 100,000	$ 50,000	$ 184,000	$ 100,000	$ 50,000	$ 125,000
Percentage of Interest accrues								3.25%	4.00%	3.25%	3.25%	3.25%	3.25%
Revolving credit facility commitment			75,000,000	50,000,000		50,000,000	30,000,000
Spread on Libor variable rate			2.50%	1.60%
Spread on base variable rate			1.00%	1.00%
Percentage of unused commitment fee			0.25%	1.00%
Revolving credit outstanding					16,100,000
Remaining revolving credit outstanding					58,900,000
Notes Payable (Additional Textual) [Abstract]
Purchase of common stock under credit agreement		15,000,000
Company's consolidated leverage ratio	less than 1.0 to 1.0
Maturity start date	Aug. 31, 2011
Maturity end date	Aug. 31, 2015
Aggregate principal installments	125,000
Purchase of a clinic entered into a note payable	100,000
Number of annual installments	2
Annual installments for notes payable	$ 50,000