PROPERTY AND EQUIPMENT - Summary (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Property and Equipment
Computer software, including licenses and internally-developed software	$ 69,006	$ 61,468
Furniture and equipment	31,218	28,663
Leasehold improvements	7,300	8,124
Total	107,524	98,255
Accumulated depreciation and amortization	(68,122)	(66,028)
Property and equipment, net	$ 39,402	$ 32,227

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
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 1
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-Subparagraph (SX 210.5-02.14)
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- Definition

Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount before accumulated depreciation of fixtures and equipment. Includes, but is not limited to, machinery, equipment, and engines.

+ References

No definition available.

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- Definition

Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

+ References

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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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-Paragraph 1
-Subparagraph (SX 210.5-02.13)
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Subparagraph (SX 210.5-02(13))
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