REVENUES (Tables)

12 Months Ended

Dec. 31, 2023

Revenue from Contract with Customer [Abstract]

Schedule of Disaggregation of Revenues

The following tables present the disaggregation of the Company’s revenues by major customer location, including a reconciliation of the disaggregated revenues with the Company’s reportable segments (Note 18 “Segment Information”) for the years ended December 31, 2023, 2022 and 2021:

	Year Ended December 31, 2023
	Reportable Segments
	North America		Europe		Russia		Consolidated Revenues
Customer Locations
Americas	$	2,645,174	$	96,857	$	631	$	2,742,662
EMEA	116,054		1,706,728		—		1,822,782
APAC	3,248		98,890		—		102,138
CEE	546		6,968		15,444		22,958
Revenues	$	2,765,022	$	1,909,443	$	16,075	$	4,690,540

	Year Ended December 31, 2022
	Reportable Segments
	North America		Europe		Russia		Consolidated Revenues
Customer Locations
Americas	$	2,792,156	$	92,244	$	2,804	$	2,887,204
EMEA	95,706		1,642,114		99		1,737,919
APAC	3,837		116,533		—		120,370
CEE	6,855		2,165		70,185		79,205
Revenues	$	2,898,554	$	1,853,056	$	73,088	$	4,824,698

	Year Ended December 31, 2021
	Reportable Segments
	North America		Europe		Russia		Consolidated Revenues
Customer Locations
Americas	$	2,145,163	$	77,351	$	4,316	$	2,226,830
EMEA	87,121		1,172,267		329		1,259,717
APAC	3,224		100,335		—		103,559
CEE	6,740		531		160,767		168,038
Revenues	$	2,242,248	$	1,350,484	$	165,412	$	3,758,144

The following tables present the disaggregation of the Company’s revenues by industry vertical, including a reconciliation of the disaggregated revenues with the Company’s reportable segments (Note 18 “Segment Information”) for the years ended December 31, 2023, 2022 and 2021:

	Year Ended December 31, 2023
	Reportable Segments
	North America		Europe		Russia		Consolidated Revenues
Industry Verticals
Travel & Consumer	$	472,350	$	596,830	$	3,770	$	1,072,950
Financial Services	538,837		472,146		7,450		1,018,433
Business Information & Media	429,800		323,985		196		753,981
Software & Hi-Tech	552,492		153,683		1,545		707,720
Life Sciences & Healthcare	429,245		60,549		120		489,914
Emerging Verticals	342,298		302,250		2,994		647,542
Revenues	$	2,765,022	$	1,909,443	$	16,075	$	4,690,540

	Year Ended December 31, 2022
	Reportable Segments
	North America		Europe		Russia		Consolidated Revenues
Industry Verticals
Travel & Consumer	$	505,227	$	571,437	$	15,560	$	1,092,224
Financial Services	522,970		460,858		42,858		1,026,686
Business Information & Media	467,664		341,344		944		809,952
Software & Hi-Tech	655,122		136,273		1,866		793,261
Life Sciences & Healthcare	454,102		52,465		800		507,367
Emerging Verticals	293,469		290,679		11,060		595,208
Revenues	$	2,898,554	$	1,853,056	$	73,088	$	4,824,698

	Year Ended December 31, 2021
	Reportable Segments
	North America		Europe		Russia		Consolidated Revenues
Industry Verticals
Travel & Consumer	$	359,306	$	354,041	$	27,781	$	741,128
Financial Services	361,611		372,394		114,365		848,370
Business Information & Media	389,613		275,502		1,826		666,941
Software & Hi-Tech	559,707		102,270		2,620		664,597
Life Sciences & Healthcare	340,706		49,900		703		391,309
Emerging Verticals	231,305		196,377		18,117		445,799
Revenues	$	2,242,248	$	1,350,484	$	165,412	$	3,758,144

The following tables present the disaggregation of the Company’s revenues by contract type, including a reconciliation of the disaggregated revenues with the Company’s reportable segments (Note 18 “Segment Information”) for the years ended December 31, 2023, 2022 and 2021:

	Year Ended December 31, 2023
	Reportable Segments
	North America		Europe		Russia		Consolidated Revenues
Contract Types
Time-and-material	$	2,457,545	$	1,613,790	$	11,168	$	4,082,503
Fixed-price	283,183		291,174		4,873		579,230
Licensing and other revenues	24,294		4,479		34		28,807
Revenues	$	2,765,022	$	1,909,443	$	16,075	$	4,690,540

	Year Ended December 31, 2022
	Reportable Segments
	North America		Europe		Russia		Consolidated Revenues
Contract Types
Time-and-material	$	2,615,213	$	1,578,786	$	45,581	$	4,239,580
Fixed-price	263,603		269,669		27,195		560,467
Licensing and other revenues	19,738		4,601		312		24,651
Revenues	$	2,898,554	$	1,853,056	$	73,088	$	4,824,698

	Year Ended December 31, 2021
	Reportable Segments
	North America		Europe		Russia		Consolidated Revenues
Contract Types
Time-and-material	$	1,981,696	$	1,145,606	$	82,445	$	3,209,747
Fixed-price	244,249		202,436		82,711		529,396
Licensing and other revenues	16,303		2,442		256		19,001
Revenues	$	2,242,248	$	1,350,484	$	165,412	$	3,758,144

Timing of Revenue Recognition

The following tables present the revenues disaggregated by timing of revenue recognition and reconciled with the Company’s reportable segments (Note 18 “Segment Information”) for the years ended December 31, 2023, 2022 and 2021:

	Year Ended December 31, 2023
	Reportable Segments
	North America		Europe		Russia		Consolidated Revenues
Timing of Revenue Recognition
Transferred over time	$	2,751,937	$	1,907,010	$	16,042	$	4,674,989
Transferred at a point of time	13,085		2,433		33		15,551
Revenues	$	2,765,022	$	1,909,443	$	16,075	$	4,690,540

	Year Ended December 31, 2022
	Reportable Segments
	North America		Europe		Russia		Consolidated Revenues
Timing of Revenue Recognition
Transferred over time	$	2,888,342	$	1,849,011	$	72,795	$	4,810,148
Transferred at a point of time	10,212		4,045		293		14,550
Revenues	$	2,898,554	$	1,853,056	$	73,088	$	4,824,698

	Year Ended December 31, 2021
	Reportable Segments
	North America		Europe		Russia		Consolidated Revenues
Timing of Revenue Recognition
Transferred over time	$	2,232,308	$	1,349,956	$	165,301	$	3,747,565
Transferred at a point of time	9,940		528		111		10,579
Revenues	$	2,242,248	$	1,350,484	$	165,412	$	3,758,144

Schedule of Revenue Expected to be Recognized in Future Related to Remaining Performance Obligations

The following table includes the estimated revenues expected to be recognized in the future related to performance obligations that are partially or fully unsatisfied as of December 31, 2023. The Company applies a practical expedient and does not disclose the value of unsatisfied performance obligations for contracts that (i) have an original expected duration of one year or less and (ii) contracts for which it recognizes revenues at the amount to which it has the right to invoice for services provided:

	Less than 1 year		1 Year		2 Years		3 Years		Total
Contract Type
Fixed-price	$	6,678	$	810	$	203	$	—	$	7,691

Schedule of Contract Balances

The following table provides information on the classification of contract assets and liabilities in the consolidated balance sheets:

	As of December 31, 2023		As of December 31, 2022
Contract assets included in Trade receivables and contract assets	$	24,309	$	11,490
Contract liabilities included in Accrued expenses and other current liabilities	$	27,988	$	36,036
Contract liabilities included in Other noncurrent liabilities	$	951	$	42