Significant Accounting Policies - Percentage of Net Service Revenue Contributed from Each Reporting Segment (Detail) - Sales Revenue, Segment	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
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	76.60%	77.20%	76.30%	77.70%
Hospice services
Health Care Organization, Revenue [Abstract]
Percentage of net service revenue	9.30%	9.00%	9.00%	9.10%
Community-based services
Health Care Organization, Revenue [Abstract]
Percentage of net service revenue	5.10%	4.50%	5.10%	2.60%
Facility-based services
Health Care Organization, Revenue [Abstract]
Percentage of net service revenue	9.00%	9.30%	9.60%	10.60%