Acquisitions of Businesses (Details)										3 Months Ended				6 Months Ended				9 Months Ended				12 Months Ended
	Nov. 30, 2016 USD ($) Installment	Feb. 29, 2016 USD ($) Installment	Dec. 31, 2015 USD ($) Installment	Aug. 31, 2015 USD ($)	Jun. 30, 2015 USD ($)	Apr. 30, 2015 USD ($) Installment	Jan. 31, 2015 USD ($) Installment	Aug. 31, 2014 USD ($)	Apr. 30, 2014 USD ($) Installment	Mar. 31, 2016 USD ($)	[1]	Mar. 31, 2015 USD ($)	[1]	Jun. 30, 2016 USD ($)	[1]	Jun. 30, 2015 USD ($)		Sep. 30, 2016 USD ($)	[1]	Sep. 30, 2015 USD ($)	[1]	Dec. 31, 2016 USD ($) Clinic Subsidiary Operation	Dec. 31, 2015 USD ($) Clinic		Dec. 31, 2014 USD ($) Clinic
Business Acquisition [Line Items]
Seller notes issued for acquisition of interest in clinic			$ 1,800,000																			$ 1,000,000	$ 1,800,000		$ 400,000
Number of acquired operations combined | Operation																						2
Cash paid, net of cash acquired										$ 12,899,000		$ 6,445,000		$ 12,958,000		$ 14,467,000	[1]	$ 12,958,000		$ 14,434,000		$ 23,623,000	18,965,000	[1]	12,270,000	[1]
Seller notes			1,800,000																			1,000,000	1,800,000		400,000
Total consideration			20,765,000																			24,623,000	20,765,000		12,670,000
Estimated fair value of net tangible assets acquired: [Abstract]
Total current assets			1,952,000																			1,712,000	1,952,000		1,213,000
Total non-current assets			1,068,000																			1,202,000	1,068,000		1,051,000
Total liabilities			(1,067,000)																			(398,000)	(1,067,000)		(406,000)
Net tangible assets acquired			1,953,000																			2,516,000	1,953,000		1,858,000
Referral relationships			3,655,000																			4,919,000	3,655,000		280,000
Non-compete			594,000																			847,000	594,000		330,000
Tradename			3,417,000																			3,802,000	3,417,000		1,600,000
Goodwill			23,437,000																			31,419,000	23,437,000		13,327,000
Fair value of noncontrolling interest			(12,291,000)																			(18,880,000)	(12,291,000)		(4,725,000)
Total consideration			$ 20,765,000																			$ 24,623,000	$ 20,765,000		$ 12,670,000
Minimum [Member]
Business Acquisition [Line Items]
Percentage of interest acquired			5.00%																			2.00%	5.00%
Maximum [Member]
Business Acquisition [Line Items]
Percentage of interest acquired			35.00%																			35.00%	35.00%
Referral Relationships [Member] | Minimum [Member]
Business Acquisition [Line Items]
Estimated useful lives of acquired intangibles																						4 years 6 months
Referral Relationships [Member] | Maximum [Member]
Business Acquisition [Line Items]
Estimated useful lives of acquired intangibles																						13 years
Non-compete Agreements [Member] | Minimum [Member]
Business Acquisition [Line Items]
Estimated useful lives of acquired intangibles																						5 years
Non-compete Agreements [Member] | Maximum [Member]
Business Acquisition [Line Items]
Estimated useful lives of acquired intangibles																						6 years
Tradenames [Member]
Business Acquisition [Line Items]
Estimated useful lives of acquired intangibles																						6 years
February 2017 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest																						$ 194,000
February 2018 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest																						$ 194,000
February 2016 Acquisition [Member]
Business Acquisition [Line Items]
Acquisition date																						Feb. 29, 2016
Percentage of interest acquired																						55.00%
Number of clinics | Clinic																						8
November 2016 Acquisition [Member]
Business Acquisition [Line Items]
Acquisition date																						Nov. 30, 2016
Percentage of interest acquired																						60.00%
Number of clinics | Clinic																						12
January 2015 Acquisition [Member]
Business Acquisition [Line Items]
Acquisition date																							Jan. 31, 2015
Percentage of interest acquired			60.00%																				60.00%
Number of clinics | Clinic																							9
April 2015 Acquisition [Member]
Business Acquisition [Line Items]
Acquisition date																							Apr. 30, 2015
Percentage of interest acquired			70.00%																				70.00%
Number of clinics | Clinic																							3
June 2015 Acquisition [Member]
Business Acquisition [Line Items]
Acquisition date																							Jun. 30, 2015
Percentage of interest acquired			70.00%																				70.00%
Number of clinics | Clinic																							4
December 2015 Acquisition [Member]
Business Acquisition [Line Items]
Acquisition date																							Dec. 31, 2015
Percentage of interest acquired			59.00%																				59.00%
Number of clinics | Clinic																							4
April 2014 Acquisition [Member]
Business Acquisition [Line Items]
Acquisition date																									Apr. 30, 2014
Percentage of interest acquired																									70.00%
Number of clinics | Clinic																									13
August 2014 Acquisition [Member]
Business Acquisition [Line Items]
Acquisition date																									Aug. 01, 2014
Percentage of interest acquired																									100.00%
Number of clinics | Clinic																									3
Acquisition Of Single Clinic Practices [Member]
Business Acquisition [Line Items]
Percentage of interest acquired			60.00%	60.00%																			60.00%
Number of clinics | Clinic																						2	1		4
Cash paid for acquisition of interest in clinic				$ 150,000
Seller notes issued for acquisition of interest in clinic				50,000
Aggregate purchase price for the acquired clinic practices																						$ 75,000
Number of subsidiaries acquired clinic practices | Subsidiary																						2
Seller notes				50,000
Acquisition Of Single Clinic Practices [Member] | August 2016 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest				$ 50,000
Acquisition Of Three Clinic Practices [Member]
Business Acquisition [Line Items]
Percentage of interest acquired						70.00%
Cash paid for acquisition of interest in clinic						$ 4,700,000		$ 1,000,000
Seller notes issued for acquisition of interest in clinic						$ 150,000																			$ 595,000
Business acquisition number of installments to payment of purchase consideration | Installment						2
Seller notes						$ 150,000																			$ 595,000
Acquisition Of Three Clinic Practices [Member] | April 2016 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest						75,000
Acquisition Of Three Clinic Practices [Member] | April 2017 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest						$ 75,000
Acquisition Of Four Clinic Practices [Member]
Business Acquisition [Line Items]
Percentage of interest acquired			59.00%		70.00%											70.00%							59.00%
Cash paid for acquisition of interest in clinic			$ 4,600,000		$ 3,600,000
Seller notes issued for acquisition of interest in clinic			$ 400,000		700,000											$ 700,000							$ 400,000
Business acquisition number of installments to payment of purchase consideration | Installment			2
Seller notes			$ 400,000		700,000											$ 700,000							$ 400,000
Acquisition Of Four Clinic Practices [Member] | December 2016 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest			200,000
Acquisition Of Four Clinic Practices [Member] | December 2017 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest			$ 200,000
Acquisition Of Four Clinic Practices [Member] | June 2018 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest					$ 700,000
Acquisition Of Eight Clinic Practices [Member]
Business Acquisition [Line Items]
Percentage of interest acquired		55.00%
Cash paid for acquisition of interest in clinic		$ 13,200,000
Seller notes issued for acquisition of interest in clinic		$ 500,000
Business acquisition number of installments to payment of purchase consideration | Installment		2
Seller notes		$ 500,000
Acquisition Of Eight Clinic Practices [Member] | February 2017 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest		250,000
Acquisition Of Eight Clinic Practices [Member] | February 2018 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest		$ 250,000
Acquisition Of Nine Clinic Practices [Member]
Business Acquisition [Line Items]
Percentage of interest acquired							60.00%
Cash paid for acquisition of interest in clinic							$ 6,700,000
Seller notes issued for acquisition of interest in clinic							$ 500,000
Business acquisition number of installments to payment of purchase consideration | Installment							2
Seller notes							$ 500,000
Acquisition Of Nine Clinic Practices [Member] | January 2016 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest							250,000
Acquisition Of Nine Clinic Practices [Member] | January 2017 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest							$ 250,000
Acquisition Of Twelve Clinic Practices [Member]
Business Acquisition [Line Items]
Percentage of interest acquired	60.00%
Cash paid for acquisition of interest in clinic	$ 11,000,000
Seller notes issued for acquisition of interest in clinic	$ 500,000
Business acquisition number of installments to payment of purchase consideration | Installment	2
Seller notes	$ 500,000
Acquisition Of Twelve Clinic Practices [Member] | November 2017 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest	250,000
Acquisition Of Twelve Clinic Practices [Member] | November 2018 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest	$ 250,000
Acquisition Of Thirteen Clinic Practices [Member]
Business Acquisition [Line Items]
Percentage of interest acquired									70.00%
Cash paid for acquisition of interest in clinic									$ 10,600,000
Seller notes issued for acquisition of interest in clinic									$ 400,000
Business acquisition number of installments to payment of purchase consideration | Installment									2
Seller notes									$ 400,000
Acquisition Of Thirteen Clinic Practices [Member] | April 2016 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest									200,000
Acquisition Of Thirteen Clinic Practices [Member] | April 2015 [Member]
Business Acquisition [Line Items]
Acquisition cost payable in two principal installments including accrued interest									$ 200,000

[1] as restated