Operating Income of Reportable Segments (Detail) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Segment Reporting Information [Line Items]
Net service revenue	$ 378,498,000	$ 368,424,000	$ 749,331,000	$ 727,738,000
Cost of service, excluding depreciation and amortization	212,266,000	189,426,000	420,772,000	376,730,000
General and administrative expenses	136,083,000	127,121,000	270,036,000	256,715,000
Provision for doubtful accounts	4,695,000	2,266,000	10,558,000	5,380,000
Depreciation and amortization	9,905,000	9,550,000	19,959,000	18,730,000
Operating expenses	362,949,000	328,363,000	721,325,000	657,555,000
Operating (loss) income	15,549,000	40,061,000	28,006,000	70,183,000
Home Health
Segment Reporting Information [Line Items]
Net service revenue	304,800,000	321,600,000	606,200,000	642,400,000
Cost of service, excluding depreciation and amortization	174,300,000	164,200,000	346,300,000	331,300,000
General and administrative expenses	68,400,000	70,500,000	138,800,000	144,000,000
Provision for doubtful accounts	4,000,000	2,200,000	9,100,000	5,300,000
Depreciation and amortization	3,400,000	3,700,000	6,600,000	6,700,000
Operating expenses	250,100,000	240,600,000	500,800,000	487,300,000
Operating (loss) income	54,700,000	81,000,000	105,400,000	155,100,000
Hospice care centers
Segment Reporting Information [Line Items]
Net service revenue	73,700,000	46,800,000	143,100,000	85,300,000
Cost of service, excluding depreciation and amortization	38,000,000	25,200,000	74,500,000	45,400,000
General and administrative expenses	13,400,000	9,200,000	26,100,000	17,100,000
Provision for doubtful accounts	700,000	100,000	1,500,000	100,000
Depreciation and amortization	300,000	200,000	600,000	300,000
Operating expenses	52,400,000	34,700,000	102,700,000	62,900,000
Operating (loss) income	21,300,000	12,100,000	40,400,000	22,400,000
Other
Segment Reporting Information [Line Items]
General and administrative expenses	54,300,000	47,400,000	105,100,000	95,600,000
Depreciation and amortization	6,200,000	5,600,000	12,700,000	11,700,000
Operating expenses	60,500,000	53,000,000	117,800,000	107,300,000
Operating (loss) income	$ (60,500,000)	$ (53,000,000)	$ (117,800,000)	$ (107,300,000)