CONSOLIDATED STATEMENTS OF NET INCOME (unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
CONSOLIDATED STATEMENTS OF NET INCOME (unaudited) [Abstract]
Net patient revenues	$ 88,433	$ 81,451	$ 173,482	$ 157,258
Other revenues	1,997	1,837	3,856	3,271
Net revenues	90,430	83,288	177,338	160,529
Clinic operating costs:
Salaries and related costs	48,837	44,398	96,641	87,450
Rent, clinic supplies, contract labor and other	17,546	16,681	35,053	33,006
Provision for doubtful accounts	956	1,062	2,045	2,052
Closure costs	32	5	45	37
Total clinic operating costs	67,371	62,146	133,784	122,545
Gross margin	23,059	21,142	43,554	37,984
Corporate office costs	8,026	7,593	17,030	15,250
Operating income	15,033	13,549	26,524	22,734
Interest and other income, net	21	16	41	24
Interest expense	(320)	(245)	(628)	(510)
Income before taxes	14,734	13,320	25,937	22,248
Provision for income taxes	4,674	4,203	8,197	6,980
Net income including non-controlling interests	10,060	9,117	17,740	15,268
Less: net income attributable to non-controlling interests	(2,989)	(2,813)	(5,341)	(4,798)
Net income attributable to common shareholders	$ 7,071	$ 6,304	$ 12,399	$ 10,470
Basic earnings per share attributable to common shareholders:
From operations prior to revaluation of redeemable non-controlling interests, net of tax (in dollars per share)	$ 0.57	$ 0.51	$ 0.99	$ 0.85
Charges to additional paid-in-capital - revaluation of redeemable non-controlling interests, net of tax (in dollars per share)	0	(0.03)	0	(0.03)
Basic (in dollars per share)	0.57	0.48	0.99	0.82
Diluted earnings per share attributable to common shareholders:
From operations prior to revaluation of redeemable non-controlling interests, net of tax (in dollars per share)	0.57	0.51	0.99	0.85
Charges to additional paid-in-capital - revaluation of redeemable non-controlling interests, net of tax (in dollars per share)	0	(0.03)	0	(0.03)
Diluted (in dollars per share)	$ 0.57	$ 0.48	$ 0.99	$ 0.82
Shares used in computation:
Basic and diluted (in shares)	12,511	12,409	12,480	12,362
Dividends declared per common share (in dollars per share)	$ 0.17	$ 0.15	$ 0.34	$ 0.30