Nature of Operations Consolidation and Presentation of Financial Statements - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2012 State	Dec. 31, 2011	Dec. 31, 2010
Organization and Nature of Operations [Line Items]
Percent of net services revenue provided by Medicare	82.00%	85.00%	86.00%
Medicare-certified home health care centers	435
Medicare-certified hospice agencies	97
Hospice inpatient units	2
Number of states with facilities	38
Number of care centers closed	3	29	23
Minimum percent ownership for controlling interest percent	50.00%