1. NATURE OF BUSINESS AND BASIS OF PRESENTATION (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Commercial Insurance/Managed Care Capitation	$ 122,693	$ 115,332	$ 243,043	$ 228,788
Medicare	36,815	34,500	72,591	68,107
Medicaid	6,285	5,833	11,997	11,572
Workers Compensation/Personal Injury	8,802	7,500	18,307	14,878
Other	8,880	8,581	17,299	16,901
Service fee revenue, net of contractual allowances and discounts	183,475	171,746	363,237	340,246
Provision for bad debts	(6,955)	(6,395)	(13,777)	(12,879)
Net service fee revenue	$ 176,520	$ 165,351	$ 349,460	$ 327,367

Commercial Insurance/Managed Care Capitation

No definition available.

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- Definition

Medicare income

+ References

No definition available.

+ Details

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- Definition

Workers comp arrangement

+ References

No definition available.

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- Definition

Amount of revenue recognized that is not otherwise disclosed.

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- Definition

Amount of patient service revenue, net of contractual allowances and discounts, less the related provision for bad debts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 954

-SubTopic 605

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=9156363&loc=SL9156442-115640

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- Definition

Amount of the provision for bad debts related to patient service revenue.

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- Definition

Amount of insurance premium revenue recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(e))

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-HCO

-Paragraph 10

-IssueDate 2006-05-01

-Chapter 8

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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- Definition

Amount of revenues recognized by the entity from providing services to in-patients, outpatients, residents in facilities owned or operated by the entity, from insurance premiums, or from goods provided or services performed.

+ References

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