Significant Accounting Policies - Percentage of Net Service Revenue Contributed from Each Reporting Segment (Detail) - Sales Revenue, Segment	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Health Care Organization, Revenue [Abstract]
Percentage of net service revenue	100.00%	100.00%	100.00%	100.00%
Home health services
Health Care Organization, Revenue [Abstract]
Percentage of net service revenue	72.60%	76.00%	72.50%	76.20%
Hospice Services
Health Care Organization, Revenue [Abstract]
Percentage of net service revenue	15.30%	9.40%	14.70%	9.10%
Community-based services
Health Care Organization, Revenue [Abstract]
Percentage of net service revenue	5.10%	5.20%	4.80%	5.10%
Facility-based services
Health Care Organization, Revenue [Abstract]
Percentage of net service revenue	7.00%	9.40%	8.00%	9.60%