IMPACT OF THE INVASION OF UKRAINE - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 04, 2022	Dec. 31, 2021
Unusual or Infrequent Item, or Both [Line Items]
Property and equipment, net	$ 219,639,000			$ 236,214,000
Operating lease, right-of-use asset	175,514,000			184,841,000
Commitments related to operating lease agreements that have not yet commenced	12,300,000
Goodwill impairment	686,000
Bad debt expense	8,675,000	$ 2,925,000
Impairment charges	20,401,000	$ 0
Humanitarian Commitment
Unusual or Infrequent Item, or Both [Line Items]
Nonoperating expense	25,700,000
Humanitarian Commitment | Cost of revenues (exclusive of depreciation and amortization)
Unusual or Infrequent Item, or Both [Line Items]
Nonoperating expense	19,200,000
Humanitarian Commitment | Selling, general and administrative expenses
Unusual or Infrequent Item, or Both [Line Items]
Nonoperating expense	6,500,000
Ukraine
Unusual or Infrequent Item, or Both [Line Items]
Property and equipment, net	74,902,000			78,289,000
Operating lease, right-of-use asset	18,800,000
Ukraine | Cost of revenues (exclusive of depreciation and amortization)
Unusual or Infrequent Item, or Both [Line Items]
Standby resources expense	2,600,000
Ukraine | Selling, general and administrative expenses
Unusual or Infrequent Item, or Both [Line Items]
Standby resources expense	18,700,000
Ukraine | Other Income/(Expense)
Unusual or Infrequent Item, or Both [Line Items]
Impairment charges	1,300,000
Ukraine | Humanitarian Commitment
Unusual or Infrequent Item, or Both [Line Items]
Commitments related to operating lease agreements that have not yet commenced			$ 100,000,000
Russia
Unusual or Infrequent Item, or Both [Line Items]
Property and equipment, net	0			$ 16,611,000
Impairment of property, plant and equipment	15,100,000
Operating Lease, Impairment Loss	3,800,000
Goodwill impairment	700,000
Bad debt expense	8,400,000
Building | Ukraine
Unusual or Infrequent Item, or Both [Line Items]
Property and equipment, net	74,900,000
Construction in Progress | Ukraine
Unusual or Infrequent Item, or Both [Line Items]
Property and equipment, net	50,400,000
Computer Equipment | Ukraine
Unusual or Infrequent Item, or Both [Line Items]
Property and equipment, net	15,300,000
Furniture and Fixtures | Ukraine
Unusual or Infrequent Item, or Both [Line Items]
Property and equipment, net	8,500,000
Leasehold Improvements | Ukraine
Unusual or Infrequent Item, or Both [Line Items]
Property and equipment, net	$ 700,000