Schedule of intangible assets (Detail) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross, Total, Beginning Balance	$ 144,476,000	$ 144,476,000
Accumulated Amortization	(49,548,964)	(40,942,442)
Intangible Assets, Net	94,927,036	103,533,558
Medicare License
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross, Total, Beginning Balance	1,994,000	1,994,000
Accumulated Amortization	0	0
Intangible Assets, Net	1,994,000	1,994,000
Network relationships
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross, Total, Beginning Balance	109,883,000	109,883,000
Accumulated Amortization	(42,332,259)	(35,842,508)
Intangible Assets, Net	$ 67,550,741	$ 74,040,492
Network relationships | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Life (Yrs)	15 years	15 years
Network relationships | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Life (Yrs)	11 years	11 years
Trade name
Finite-Lived Intangible Assets [Line Items]
Weighted Average Life (Yrs)	20 years	20 years
Intangible Assets, Gross, Total, Beginning Balance	$ 1,011,000	$ 1,011,000
Accumulated Amortization	(29,487)	(4,212)
Intangible Assets, Net	$ 981,513	$ 1,006,788
Management contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Life (Yrs)	15 years	15 years
Intangible Assets, Gross, Total, Beginning Balance	$ 22,832,000	$ 22,832,000
Accumulated Amortization	(6,278,801)	(5,014,886)
Intangible Assets, Net	$ 16,553,199	$ 17,817,114
Member relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Life (Yrs)	12 years	12 years
Intangible Assets, Gross, Total, Beginning Balance	$ 6,696,000	$ 6,696,000
Accumulated Amortization	(668,084)	(46,500)
Intangible Assets, Net	$ 6,027,916	$ 6,649,500
Patient management platform [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Life (Yrs)	5 years	5 years
Intangible Assets, Gross, Total, Beginning Balance	$ 2,060,000	$ 2,060,000
Accumulated Amortization	(240,333)	(34,336)
Intangible Assets, Net	$ 1,819,667	$ 2,025,664