Acquisitions and Disposals - Additional Information (Detail) $ in Thousands		12 Months Ended
	Nov. 11, 2015 Agency	Dec. 31, 2015 USD ($) Agency	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Oct. 01, 2015 USD ($)
Business Acquisition [Line Items]
Intangible Assets, Net (Excluding Goodwill)		$ 96,405	$ 79,685
Goodwill Current Year Acquisition		290,694	240,019	$ 194,893
Total purchase price for acquisitions			75,500
Cash		70,572	73,933	26,920
Gain (Loss) on Disposition of Intangible Assets		$ (300)	(1,400)
Minimum [Member]
Business Acquisition [Line Items]
Estimated useful life		1 year
Maximum [Member]
Business Acquisition [Line Items]
Estimated useful life		3 years
Community-Based Services [Member]
Business Acquisition [Line Items]
Intangible Assets, Net (Excluding Goodwill)		$ 7,300
Home Health Reporting Unit [Member]
Business Acquisition [Line Items]
Goodwill Current Year Acquisition		202,995	196,296	173,574
Goodwill Recognized			22,900
Community Based Reporting Unit [Member]
Business Acquisition [Line Items]
Goodwill Current Year Acquisition		17,972	17,339	265
Goodwill Recognized			17,100
Hospice Reporting Unit [Member]
Business Acquisition [Line Items]
Goodwill Current Year Acquisition		$ 58,136	14,793	$ 9,463
Goodwill Recognized			5,300
General and Administrative Expense [Member]
Business Acquisition [Line Items]
Acquisition-related cost			$ 1,000
Halcyon Healthcare [Member]
Business Acquisition [Line Items]
Ownership Percentage					100.00%
Number of entities acquired | Agency		16
Nurses Registry [Member]
Business Acquisition [Line Items]
Ownership Percentage	100.00%
Number of entities acquired | Agency	5
Goodwill Current Year Acquisition					$ 47,200
Nurses Registry [Member] | Home Health Reporting Unit [Member]
Business Acquisition [Line Items]
Number of entities acquired | Agency	4
Nurses Registry [Member] | Community Based Reporting Unit [Member]
Business Acquisition [Line Items]
Number of entities acquired | Agency	1
Other Agencies Acquired | Home Health Reporting Unit [Member]
Business Acquisition [Line Items]
Number of entities acquired | Agency		5
Other Agencies Acquired | Community Based Reporting Unit [Member]
Business Acquisition [Line Items]
Number of entities acquired | Agency		1
Other Agencies Acquired | Hospice Reporting Unit [Member]
Business Acquisition [Line Items]
Number of entities acquired | Agency		1
2015 Acquisitions [Member]
Business Acquisition [Line Items]
Total consideration transferred		$ 71,400
Cash		70,123
2015 Acquisitions [Member] | Home Health Reporting Unit [Member]
Business Acquisition [Line Items]
Goodwill Recognized		7,100
2015 Acquisitions [Member] | Community Based Reporting Unit [Member]
Business Acquisition [Line Items]
Goodwill Recognized		600
2015 Acquisitions [Member] | Hospice Reporting Unit [Member]
Business Acquisition [Line Items]
Goodwill Recognized		43,300
2015 Acquisitions [Member] | General and Administrative Expense [Member]
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs		$ 400