Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Subsequent Events (Details)	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Dec. 31, 2009 USD ($)	Aug. 31, 2011 Revolving Credit [Member] USD ($)	Aug. 31, 2010 Revolving Credit [Member] USD ($)	Jan. 24, 2012 AVC [Member] USD ($)	Jan. 31, 2012 Acquisition [Member] AVC [Member] CAD Hospitals Province	Jan. 25, 2012 Refinancing of Debt [Member] Revolving Credit [Member] USD ($)
Subsequent Event [Line Items]
Investment in AVC							81,000,000
Maximum borrowings of wholly-owned subsidiary under revolving line of credit				125,000,000	100,000,000			100,000,000
Cash paid for acquisitions	$ (203,996,000)	$ (79,851,000)	$ (74,567,000)			$ 50,000,000
Number of hospitals operated by AVC							44
Number of Canadian provinces AVC operates within							3