Nature of Operations Consolidation and Presentation of Financial Statements - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($) Agencies States	Dec. 31, 2015 USD ($)	Dec. 31, 2014	Sep. 30, 2016
Organization And Nature Of Operations [Line Items]
Percent Of Net Services Revenue Provided By Medicare	78.00%	80.00%	82.00%
Number Of States With Facilities | States	34
Minimum percent ownership for controlling interest percent	50.00%
Equity Method Investment Aggregate Cost | $	$ 27.8	$ 25.7
Maximum Percent Ownership For Equity Method Percent	50.00%
Maximum Percent Ownership For Cost Method Percent	20.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners				30.00%
Home Health [Member]
Organization And Nature Of Operations [Line Items]
Operating Care Centers	327
Hospice [Member]
Organization And Nature Of Operations [Line Items]
Operating Care Centers	79
Personal Care [Member]
Organization And Nature Of Operations [Line Items]
Operating Care Centers	14