PROPERTY AND EQUIPMENT (Details) - USD ($)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property and Equipment
Property and equipment, gross	$ 107,626,000	$ 93,974,000
Less: Accumulated depreciation	(75,091,000)	(62,035,000)
Property and equipment, net	32,535,000	31,939,000
Depreciation expense	21,551,000	22,743,000	$ 22,943,000
Depreciation related to software capitalized for internal use	2,200,000	2,500,000	2,400,000
Impairment of property, plant and equipment	0
Computer and office equipment
Property and Equipment
Property and equipment, gross	29,556,000	22,561,000
Software capitalized for internal use
Property and Equipment
Property and equipment, gross	16,481,000	15,600,000
Work in progress	5,800,000	1,800,000
Vehicles
Property and Equipment
Property and equipment, gross	2,552,000	1,938,000
Medical equipment
Property and Equipment
Property and equipment, gross	31,509,000	28,423,000
Work in progress
Property and Equipment
Property and equipment, gross	5,746,000	6,624,000
Furniture and fixtures
Property and Equipment
Property and equipment, gross	5,318,000	4,543,000
Leasehold improvements
Property and Equipment
Property and equipment, gross	16,464,000	14,285,000
Assets held under capital leases
Property and Equipment
Depreciation expense	$ 15,400,000	$ 17,600,000	$ 16,400,000

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

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