Nature of Operations Consolidation and Presentation of Financial Statements - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2013 Agencies States	Jun. 30, 2012	Jun. 30, 2013 Agencies States	Jun. 30, 2012	Dec. 31, 2012 Agencies
Organization And Nature Of Operations [Line Items]
Percent Of Net Services Revenue Provided By Medicare	84.00%	82.00%	84.00%	83.00%
Number Of States With Facilities	37		37
Number of care centers closed					3
Minimum percent ownership for controlling interest percent	50.00%		50.00%
Equity Method Investment Aggregate Cost	$ 5.7		$ 5.7		$ 4.8
Cost Method Investments	$ 5.0		$ 5.0
Maximum Percent Ownership For Equity Method Percent	50.00%		50.00%
Maximum Percent Ownership For Cost Method Percent	20.00%		20.00%
Number of care centers consolidated	19		28
Number of care centers included in divestiture plan	50
Number of care centers available for sale	34
Home Health [Member]
Organization And Nature Of Operations [Line Items]
Operating Care Centers	409		409
Number of care centers consolidated	17
Number of care centers available for sale	33
Hospice [Member]
Organization And Nature Of Operations [Line Items]
Operating Care Centers	94		94
Number of care centers consolidated	2
Number of care centers available for sale	1
Hospice Inpatient [Member]
Organization And Nature Of Operations [Line Items]
Operating Care Centers	1		1