Significant Accounting Policies - Percentage of Net Service Revenue Contributed from Each Reporting Segment (Detail) (Sales Revenue, Segment)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Health Care Organization, Revenue [Abstract]
Percentage of net service revenue	100.00%	100.00%
Home health services
Health Care Organization, Revenue [Abstract]
Percentage of net service revenue	75.90%	78.10%
Hospice Services
Health Care Organization, Revenue [Abstract]
Percentage of net service revenue	8.70%	9.30%
Community-based services
Health Care Organization, Revenue [Abstract]
Percentage of net service revenue	5.10%	0.50%
Facility-based services
Health Care Organization, Revenue [Abstract]
Percentage of net service revenue	10.30%	12.10%