Summary of Activity Related to Other Intangible Assets, Net (Detail) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Goodwill and Intangible Assets [Line Items]
Beginning balance	$ 36,690,000	$ 47,000,000	$ 50,000,000
Additions	0amed_OtherIntangibleAssetsAdditions	600,000amed_OtherIntangibleAssetsAdditions	4,000,000amed_OtherIntangibleAssetsAdditions
Write-off	(200,000)amed_OtherIntangiblesWriteOffs	(1,100,000)amed_OtherIntangiblesWriteOffs
Other intangibles impairment charge	(3,100,000)	(8,200,000)	(4,200,000)
Amortization	(200,000)us-gaap_AmortizationOfIntangibleAssets	(1,600,000)us-gaap_AmortizationOfIntangibleAssets	(2,800,000)us-gaap_AmortizationOfIntangibleAssets
Ending balance	33,193,000	36,690,000	47,000,000
NonCompete Agreements Reacquired Franchise Rights [Member]
Goodwill and Intangible Assets [Line Items]
Beginning balance	200,000	1,800,000	4,200,000
Additions	0	0	400,000
Write-off	0	0
Other intangibles impairment charge	0	0	0
Amortization	(200,000)	(1,600,000)	(2,800,000)
Ending balance	0	200,000	1,800,000
Certificates Of Need And Licenses [Member]
Goodwill and Intangible Assets [Line Items]
Beginning balance	25,400,000	33,700,000	34,000,000
Additions	0	600,000	3,600,000
Write-off	(200,000)	(1,100,000)
Other intangibles impairment charge	(2,100,000)	(7,800,000)	(3,900,000)
Amortization	0	0	0
Ending balance	23,100,000	25,400,000	33,700,000
Acquired Names Of Business [Member]
Goodwill and Intangible Assets [Line Items]
Beginning balance	11,100,000	11,500,000	11,800,000
Additions	0	0	0
Write-off	0	0
Other intangibles impairment charge	(1,000,000)	(400,000)	(300,000)
Amortization	0	0	0
Ending balance	$ 10,100,000	$ 11,100,000	$ 11,500,000

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Additions to Other Intangible Assets that occurred during the period

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Write-off of intangible asets that occurred during the period

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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