PROPERTY, EQUIPMENT AND SOFTWARE, NET (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Capital Leased Assets, Gross	$ 78,500	$ 120,500
Total property, equipment and software, gross	436,384	447,547
Less: accumulated depreciation and amortization	(311,434)	(304,430)
Property, equipment and software, net	124,950	143,117
Capitalized Computer Software, Net	71,100	70,900
Warehouse equipment
Property, Plant and Equipment [Line Items]
Total property, equipment and software, gross	5,144	5,265
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Total property, equipment and software, gross	9,113	9,677
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property, equipment and software, gross	47,927	50,314
Office equipment
Property, Plant and Equipment [Line Items]
Total property, equipment and software, gross	1,735	2,261
Purchased software
Property, Plant and Equipment [Line Items]
Total property, equipment and software, gross	7,207	8,523
Computer hardware
Property, Plant and Equipment [Line Items]
Total property, equipment and software, gross	143,118	174,700
Internally-developed software
Property, Plant and Equipment [Line Items]
Total property, equipment and software, gross	$ 222,140	$ 196,807

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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Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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