PROPERTY AND EQUIPMENT - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Property and equipment
Finance lease amortization	$ 174	$ 363	$ 944	$ 826
Property and equipment, gross	279,747		279,747		$ 246,605
Property and equipment	109,123		109,123		98,390
Accumulated depreciation	170,624		170,624		148,215
Excluding internal-use software and capital leases
Property and equipment
Depreciation expense	1,535	1,849	4,923	5,658
Assets under finance leases
Property and equipment
Property and equipment, gross	2,225		2,225		1,533
Accumulated depreciation	1,875		1,875		931
Internal-Use Software
Property and equipment
Property and equipment, gross	172,430		172,430		147,280
Property and equipment	91,322		91,322		76,964
Accumulated depreciation	108,881		108,881		87,281
Depreciation expense	6,881	7,561	20,139	12,906
Internal systems and tools
Property and equipment
Property and equipment, gross	40,368		40,368		$ 32,408
Depreciation expense	$ 1,228	$ 870	$ 3,253	$ 2,303

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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