PROPERTY AND EQUIPMENT (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property and Equipment
Property and equipment, gross	$ 93,974	$ 88,814
Less: Accumulated depreciation	(62,035)	(50,643)
Property and equipment, net	31,939	38,171
Depreciation expense	22,743	22,943	$ 20,226
Depreciation related to software capitalized for internal use	2,500	2,400	1,700
Computer and office equipment
Property and Equipment
Property and equipment, gross	22,561	22,662
Software capitalized for internal use
Property and Equipment
Property and equipment, gross	15,600	14,914
Work in progress	1,800	600
Vehicles
Property and Equipment
Property and equipment, gross	1,938	2,106
Medical equipment
Property and Equipment
Property and equipment, gross	28,423	27,668
Work in progress
Property and Equipment
Property and equipment, gross	6,624	3,287
Furniture and fixtures
Property and Equipment
Property and equipment, gross	4,543	4,487
Leasehold improvements
Property and Equipment
Property and equipment, gross	14,285	13,690
Assets held under capital leases
Property and Equipment
Depreciation expense	$ 17,600	$ 16,400	$ 13,400

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 360
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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For each income statement presented, the amount charged to expense for amortization of capitalized computer software costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

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-Publisher FASB
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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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-Name Regulation S-X (SX)
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