PROPERTY, EQUIPMENT AND SOFTWARE, NET (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property, equipment and software	$ 210,039	$ 168,865
Less accumulated depreciation	(106,388)	(76,425)
Property, equipment and software, net	103,651	92,440
Capitalized website and internal-use software development costs
Property, Plant and Equipment [Line Items]
Property, equipment and software	81,710	61,515
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, equipment and software	74,236	60,101
Computer equipment
Property, Plant and Equipment [Line Items]
Property, equipment and software	32,450	28,551
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, equipment and software	16,435	14,162
Telecommunication
Property, Plant and Equipment [Line Items]
Property, equipment and software	3,996	3,457
Software
Property, Plant and Equipment [Line Items]
Property, equipment and software	$ 1,212	$ 1,079

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
-Topic 360
-SubTopic 10
-Section 50
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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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+ References

Reference 1: 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(13))
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