MANDATORILY REDEEMABLE NON-CONTROLLING INTERESTS (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Jun. 30, 2017	Sep. 30, 2016
Changes in Carrying Amount of Redeemable Non-Controlling Interest [Roll Forward]
Beginning balance	$ 69,190	$ 45,974
Operating results allocated to redeemable non-controlling interest partners	4,366	3,146
Distributions to redeemable non-controlling interest partners	(5,136)	(3,955)
Changes in the redemption value of mandatorily redeemable non-controlling interest	7,839	6,056
Payments for settlement of mandatorily redeemable non-controlling interest	(2,230)	(1,136)
Purchases of businesses - initial liability related to mandatorily redeemable non-controlling interest	10,282	11,191
Ending balance	84,311	61,276
Carrying Amount of Redeemable Non-Controlling Interest [Abstract]
Contractual time period has lapsed but holder's employment has not been terminated			$ 31,448		$ 21,269
Contractual time period has not lapsed and holder's employment has not been terminated			56,092		42,576
Holder's employment has terminated and contractual time period has expired			0		0
Holder's employment has terminated and contractual time period has not expired			0		0
Redemption value prior to excess distributed earnings			87,540		63,845
Excess distributions over earnings and losses			(3,229)		(2,569)
Redeemable non-controlling interests	$ 69,190	$ 45,974	$ 84,311		$ 61,276
Therapy Practice [Member] | Minimum [Member]
Business Acquisition [Line Items]
Business acquisition, percentage of limited partnership acquired				50.00%
Therapy Practice [Member] | Maximum [Member]
Business Acquisition [Line Items]
Business acquisition, percentage of limited partnership acquired				90.00%
Therapy Practice [Member] | NewCo. [Member]
Business Acquisition [Line Items]
Percentage of equity interest of subsidiary contributed for acquisition				100.00%
Business acquisition, percentage of general partnership interest acquired				100.00%
Business acquisition, consideration payable, term of note	2 years
Employment agreement renewal term	1 year
Non-Compete agreement term under condition of termination of employment of employed selling shareholder	2 years
Therapy Practice [Member] | NewCo. [Member] | Minimum [Member]
Business Acquisition [Line Items]
Employment agreement term	3 years
Non-Compete agreement term regardless of whether the selling shareholder is employed	5 years
Required redemption term, under condition of termination of employment of employed selling shareholders	3 years
Therapy Practice [Member] | NewCo. [Member] | Maximum [Member]
Business Acquisition [Line Items]
Employment agreement term	5 years
Non-Compete agreement term regardless of whether the selling shareholder is employed	6 years
Required redemption term, under condition of termination of employment of employed selling shareholders	5 years