Other Intangible Assets - Other Identifiable Intangible Assets and Related Accumulated Amortization (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Schedule Of Finite and Indefinite Lived Other Intangible Assets [Line Items]
Intangible assets subject to amortization, Gross Carrying Amount	$ 3,247	$ 3,247
Intangible assets not subject to amortization, Gross Carrying Amount	91,036	87,348
Total	94,283	90,595
Intangible assets subject to amortization, Accumulated Amortization	(3,247)	(3,247)
Intangible assets not subject to amortization, Accumulated Amortization	0	0
Total	(3,247)	(3,247)
Contract Intangible Assets [Member]
Schedule Of Finite and Indefinite Lived Other Intangible Assets [Line Items]
Intangible assets subject to amortization, Gross Carrying Amount	2,100	2,100
Intangible assets subject to amortization, Accumulated Amortization	(2,100)	(2,100)
Non-Compete Agreements [Member]
Schedule Of Finite and Indefinite Lived Other Intangible Assets [Line Items]
Intangible assets subject to amortization, Gross Carrying Amount	1,147	1,147
Intangible assets subject to amortization, Accumulated Amortization	(1,147)	(1,147)
Licenses and Accreditations [Member]
Schedule Of Finite and Indefinite Lived Other Intangible Assets [Line Items]
Intangible assets not subject to amortization, Gross Carrying Amount	12,798	12,266
Intangible assets not subject to amortization, Accumulated Amortization	0	0
Trade Names [Member]
Schedule Of Finite and Indefinite Lived Other Intangible Assets [Line Items]
Intangible assets not subject to amortization, Gross Carrying Amount	61,413	60,586
Intangible assets not subject to amortization, Accumulated Amortization	0	0
Certificates of Need [Member]
Schedule Of Finite and Indefinite Lived Other Intangible Assets [Line Items]
Intangible assets not subject to amortization, Gross Carrying Amount	16,825	14,496
Intangible assets not subject to amortization, Accumulated Amortization	$ 0	$ 0