Acquisitions and Disposals - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) Location	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Business Acquisition [Line Items]
Intangible Assets, Net (Excluding Goodwill)	$ 102,006	$ 96,405
Number of entities acquired | Location	23
Goodwill Current Year Acquisition	$ 307,317	290,694	$ 240,019
Total purchase price for acquisitions	24,100	71,400
Cash paid for acquisitions	23,156	70,572	73,933
Acquisition related costs		400
Other	(2,000)
Deferred Tax Liabilities, Goodwill	$ 800
Minimum [Member]
Business Acquisition [Line Items]
Noncompete agreement estimated useful life	1 year
Maximum [Member]
Business Acquisition [Line Items]
Noncompete agreement estimated useful life	3 years
Community-Based Services [Member]
Business Acquisition [Line Items]
Intangible Assets, Net (Excluding Goodwill)	$ 7,400
Home Health Reporting Unit [Member]
Business Acquisition [Line Items]
Goodwill Current Year Acquisition	210,839	202,995	196,296
Community Based Reporting Unit [Member]
Business Acquisition [Line Items]
Goodwill Current Year Acquisition	18,820	17,972	17,339
Hospice Reporting Unit [Member]
Business Acquisition [Line Items]
Goodwill Current Year Acquisition	64,234	58,136	$ 14,793
2016 Acquisitions [Member]
Business Acquisition [Line Items]
Cash paid for acquisitions	$ 23,082	$ 70,100