EPAM Systems (EPAM) 10-Q 6 Aug 21 2021 Q2 Quarterly report Financial data

Cover Page

Cover Page - shares	6 Months Ended
	Jun. 30, 2021	Jul. 31, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2021
Document Transition Report	false
Entity File Number	001-35418
Entity Registrant Name	EPAM SYSTEMS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	22-3536104
Entity Address, Street Name	41 University Drive
Entity Address, Suite No.	Suite 202
Entity Address, City or Town	Newtown
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	18940
City Area Code	267
Local Phone Number	759-9000
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	EPAM
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		56,630,464
Entity Central Index Key	0001352010
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q2
Amendment Flag	false

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 1,283,233	$ 1,322,143
Short-term investments	0	60,007
Trade receivables and contract assets, net of allowance of $7,647 and $4,886, respectively	682,236	501,062
Prepaid and other current assets	72,549	29,570
Total current assets	2,038,018	1,912,782
Property and equipment, net	173,545	169,533
Operating lease right-of-use assets, net	196,572	228,672
Intangible assets, net	65,130	51,975
Goodwill	335,477	211,956
Deferred tax assets	96,115	92,454
Other noncurrent assets	56,758	53,960
Total assets	2,961,615	2,721,332
Current liabilities
Accounts payable	9,712	10,189
Accrued compensation and benefits expenses	309,328	294,709
Accrued expenses and other current liabilities	109,148	79,690
Short-term debt	25,000	0
Income taxes payable, current	16,939	20,603
Operating lease liabilities, current	52,821	60,759
Total current liabilities	522,948	465,950
Long-term debt	29	25,038
Income taxes payable, noncurrent	41,012	43,448
Operating lease liabilities, noncurrent	151,985	180,604
Other noncurrent liabilities	32,973	23,274
Total liabilities	748,947	738,314
Stockholders’ equity
Common stock, $0.001 par value; 160,000 shares authorized; 56,633 and 56,128 shares issued, 56,613 and 56,108 shares outstanding at June 30, 2021 and December 31, 2020, respectively	57	56
Additional paid-in capital	670,264	660,771
Retained earnings	1,571,597	1,347,880
Treasury stock	(177)	(177)
Accumulated other comprehensive loss	(29,073)	(25,512)
Total stockholders’ equity	2,212,668	1,983,018
Total liabilities and stockholders’ equity	$ 2,961,615	$ 2,721,332

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Current assets
Trade receivables and contract assets allowance	$ 7,647	$ 4,886
Stockholders' equity
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	160,000,000	160,000,000
Common stock, shares issued (in shares)	56,633,000	56,128,000
Common stock, shares outstanding (in shares)	56,613,000	56,108,000

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Statement [Abstract]
Revenues	$ 881,366	$ 632,383	$ 1,662,141	$ 1,283,742
Operating expenses:
Cost of revenues (exclusive of depreciation and amortization)	583,728	419,540	1,103,056	843,342
Selling, general and administrative expenses	151,910	114,191	288,299	239,299
Depreciation and amortization expense	20,454	15,226	38,261	30,166
Income from operations	125,274	83,426	232,525	170,935
Interest and other income, net	2,580	1,817	7,954	4,203
Foreign exchange loss	(4,693)	(9,167)	(2,394)	(2,643)
Income before provision for income taxes	123,161	76,076	238,085	172,495
Provision for income taxes	8,490	9,452	14,368	20,306
Net income	$ 114,671	$ 66,624	$ 223,717	$ 152,189
Net income per share:
Basic (in dollars per share)	$ 2.03	$ 1.20	$ 3.97	$ 2.74
Diluted (in dollars per share)	$ 1.94	$ 1.14	$ 3.80	$ 2.62
Shares used in calculation of net income per share:
Basic (in shares)	56,463	55,701	56,317	55,494
Diluted (in shares)	59,011	58,246	58,896	58,194

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 114,671	$ 66,624	$ 223,717	$ 152,189
Other comprehensive income/(loss):
Change in foreign currency translation adjustments, net of tax	9,637	12,442	(894)	(16,077)
Change in unrealized gain/(loss) on hedging instruments, net of tax	2,040	6,446	(2,041)	(2,922)
Defined benefit pension plans - actuarial loss, net of tax	0	0	(626)	0
Other comprehensive income/(loss)	11,677	18,888	(3,561)	(18,999)
Comprehensive income	$ 126,348	$ 85,512	$ 220,156	$ 133,190

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Restricted Stock Units (RSU)	Cumulative effect of adoption	Adjusted balance	Common Stock	Common StockRestricted Stock Units (RSU)	Common StockAdjusted balance	Additional Paid-in Capital	Additional Paid-in CapitalRestricted Stock Units (RSU)	Additional Paid-in CapitalAdjusted balance	Retained Earnings	Retained EarningsCumulative effect of adoption	Retained EarningsAdjusted balance	Treasury Stock	Treasury StockAdjusted balance	Accumulated Other Comprehensive (Loss)/Income	Accumulated Other Comprehensive (Loss)/IncomeAdjusted balance
Balance, beginning of period (in shares) at Dec. 31, 2019					55,188		55,188							20	20
Beginning balance at Dec. 31, 2019	$ 1,596,145		$ 130	$ 1,596,275	$ 55		$ 55	$ 607,051		$ 607,051	$ 1,020,590	$ 130	$ 1,020,720	$ (177)	$ (177)	$ (31,374)	$ (31,374)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock units vested (in shares)						274
Restricted stock units withheld for employee taxes (in shares)						(90)
Restricted stock units withheld for employee taxes		$ (15,822)							$ (15,822)
Stock-based compensation expense	12,210							12,210
Proceeds from stock options exercises (in shares)					217
Proceeds from stock option exercises	7,141				$ 1			7,140
Other comprehensive income (loss)	(37,887)															(37,887)
Net income	85,565										85,565
Balance, end of period (in shares) at Mar. 31, 2020					55,589									20
Ending balance at Mar. 31, 2020	1,647,482				$ 56			610,579			1,106,285			$ (177)		(69,261)
Balance, beginning of period (in shares) at Dec. 31, 2019					55,188		55,188							20	20
Beginning balance at Dec. 31, 2019	1,596,145		$ 130	$ 1,596,275	$ 55		$ 55	607,051		$ 607,051	1,020,590	$ 130	$ 1,020,720	$ (177)	$ (177)	(31,374)	$ (31,374)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss)	(18,999)
Net income	152,189
Balance, end of period (in shares) at Jun. 30, 2020					55,826									20
Ending balance at Jun. 30, 2020	1,753,094				$ 56			630,679			1,172,909			$ (177)		(50,373)
Balance, beginning of period (in shares) at Mar. 31, 2020					55,589									20
Beginning balance at Mar. 31, 2020	1,647,482				$ 56			610,579			1,106,285			$ (177)		(69,261)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock units vested (in shares)						19
Restricted stock units withheld for employee taxes (in shares)						(6)
Restricted stock units withheld for employee taxes		(1,169)							(1,169)
Stock-based compensation expense	11,153							11,153
Proceeds from stock options exercises (in shares)					224
Proceeds from stock option exercises	10,116				$ 0			10,116
Other comprehensive income (loss)	18,888															18,888
Net income	66,624										66,624
Balance, end of period (in shares) at Jun. 30, 2020					55,826									20
Ending balance at Jun. 30, 2020	$ 1,753,094				$ 56			630,679			1,172,909			$ (177)		(50,373)
Balance, beginning of period (in shares) at Dec. 31, 2020	56,108				56,108									20
Beginning balance at Dec. 31, 2020	$ 1,983,018				$ 56			660,771			1,347,880			$ (177)		(25,512)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock units vested (in shares)						248
Restricted stock units withheld for employee taxes (in shares)						(84)
Restricted stock units withheld for employee taxes		(31,935)							(31,935)
Stock-based compensation expense	14,624							14,624
Proceeds from stock options exercises (in shares)					109
Proceeds from stock option exercises	4,424							4,424
Other comprehensive income (loss)	(15,238)															(15,238)
Net income	109,046										109,046
Balance, end of period (in shares) at Mar. 31, 2021					56,381									20
Ending balance at Mar. 31, 2021	$ 2,063,939				$ 56			647,884			1,456,926			$ (177)		(40,750)
Balance, beginning of period (in shares) at Dec. 31, 2020	56,108				56,108									20
Beginning balance at Dec. 31, 2020	$ 1,983,018				$ 56			660,771			1,347,880			$ (177)		(25,512)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss)	(3,561)
Net income	$ 223,717
Balance, end of period (in shares) at Jun. 30, 2021	56,613				56,613									20
Ending balance at Jun. 30, 2021	$ 2,212,668				$ 57			670,264			1,571,597			$ (177)		(29,073)
Balance, beginning of period (in shares) at Mar. 31, 2021					56,381									20
Beginning balance at Mar. 31, 2021	2,063,939				$ 56			647,884			1,456,926			$ (177)		(40,750)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock units vested (in shares)						19
Restricted stock units withheld for employee taxes (in shares)						(6)
Restricted stock units withheld for employee taxes		$ (2,631)							$ (2,631)
Stock-based compensation expense	13,792							13,792
Proceeds from stock options exercises (in shares)					219
Proceeds from stock option exercises	11,220				$ 1			11,219
Other comprehensive income (loss)	11,677															11,677
Net income	$ 114,671										114,671
Balance, end of period (in shares) at Jun. 30, 2021	56,613				56,613									20
Ending balance at Jun. 30, 2021	$ 2,212,668				$ 57			$ 670,264			$ 1,571,597			$ (177)		$ (29,073)

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Cash flows from operating activities:
Net income	$ 223,717	$ 152,189
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense	38,261	30,166
Operating lease right-of-use assets amortization expense	31,496	33,834
Bad debt expense	2,828	3,174
Deferred taxes	1,176	2,971
Stock-based compensation expense	48,451	31,320
Other	(5,190)	4,458
Changes in assets and liabilities:
Trade receivables and contract assets	(168,038)	(11,842)
Prepaid and other assets	(7,795)	1,216
Accounts payable	(3,948)	633
Accrued expenses and other liabilities	(6,772)	(5,835)
Operating lease liabilities	(32,276)	(30,857)
Income taxes payable	(40,247)	(2,016)
Net cash provided by operating activities	81,663	209,411
Cash flows from investing activities:
Purchases of property and equipment	(33,773)	(40,524)
Purchases of short-term investments	0	(60,000)
Proceeds from short-term investments	60,000	0
Acquisition of business, net of cash acquired (Note 2)	(121,252)	(12,573)
Purchases of non-marketable securities	(2,544)	(20,500)
Other investing activities, net	179	26
Net cash used in investing activities	(97,390)	(133,571)
Cash flows from financing activities:
Proceeds from stock option exercises	15,610	17,144
Payments of withholding taxes related to net share settlements of restricted stock units	(33,696)	(15,899)
Payment of contingent consideration for previously acquired business	(1,047)	(7,869)
Other financing activities, net	137	(24)
Net cash used in financing activities	(18,996)	(6,648)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(3,761)	(11,999)
Net (decrease)/increase in cash, cash equivalents and restricted cash	(38,484)	57,193
Cash, cash equivalents and restricted cash, beginning of period	1,323,533	937,688
Cash, cash equivalents and restricted cash, end of period	1,285,049	994,881
Proceeds from short-term investments	$ 60,000	$ 0

CONDENSED CONSOLIDATED STATEM_5

CONDENSED CONSOLIDATED STATEMENT OF CASH FLOW (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Cash and cash equivalents	$ 1,283,233	$ 1,322,143
Total restricted cash	1,816	1,390
Total cash, cash equivalents, restricted cash and restricted cash equivalents	1,285,049	1,323,533
Restricted cash in Prepaid and other current assets
Restricted cash	451	106
Restricted cash in Other noncurrent assets
Restricted cash	$ 1,365	$ 1,284

BUSINESS AND SUMMARY OF SIGNIFI

BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	6 Months Ended
	Jun. 30, 2021
Accounting Policies [Abstract]
BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES EPAM Systems, Inc. (the “Company” or “EPAM”) is a leading global provider of digital platform engineering and software development services to customers located around the world, primarily in North America, Europe, Asia and Australia. The Company’s industry expertise includes financial services, travel and consumer, software and hi-tech, business information and media, life sciences and healthcare, as well as other emerging industries. The Company is incorporated in Delaware with headquarters in Newtown, Pennsylvania. Basis of Presentation — The accompanying unaudited condensed consolidated financial statements of EPAM have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP” or “U.S. GAAP”) and Article 10 of Regulation S-X under the Securities Exchange Act of 1934, as amended. The unaudited condensed consolidated financial statements include the financial statements of EPAM Systems, Inc. and its subsidiaries with all intercompany balances and transactions eliminated. These unaudited condensed consolidated financial statements and accompanying notes should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2020 included in its Annual Report on Form 10-K. The preparation of these condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in these condensed consolidated financial statements and accompanying notes. Actual results could differ from those estimates, and such differences may be material to the condensed consolidated financial statements. Operating results for the interim periods are not necessarily indicative of results that may be expected to occur for the entire year. In management’s opinion, all adjustments considered necessary for a fair presentation of the accompanying unaudited condensed consolidated financial statements have been included, and all adjustments are of a normal and recurring nature. Adoption of New Accounting Standards The adoption of new accounting standards did not have a material impact on the Company’s consolidated financial position, results of operations, changes in stockholders’ equity and cash flows. Pending Accounting Standards From time to time, new accounting pronouncements are issued by the FASB or other standards-setting bodies that the Company will adopt according to the various timetables the FASB specifies. The Company believes the impact of recently issued standards that are not yet effective will not have a material impact on its consolidated financial position, results of operations and cash flows upon adoption.

ACQUISITIONS

ACQUISITIONS	6 Months Ended
	Jun. 30, 2021
Business Combination and Asset Acquisition [Abstract]
ACQUISITIONS	ACQUISITIONS PolSource — On April 2, 2021, the Company acquired 100% of PolSource S.A. and its subsidiaries, a Salesforce Platinum Consulting Partner with more than 350 experienced Salesforce specialists for a purchase price of $136.7 million including contingent consideration with an acquisition-date fair value of $25.0 million. The Company could pay up to $45.0 million in contingent consideration and the actual future payout is subject to attainment of certain revenue, earnings and operational targets. The following table summarizes the estimated fair values of the assets acquired and liabilities assumed as of the date of acquisition for PolSource: PolSource Cash and cash equivalents $ 2,565 Trade receivables and contract assets 13,653 Prepaid and other current assets 756 Goodwill 113,528 Intangible assets 15,290 Property and equipment and other noncurrent assets 422 Total assets acquired $ 146,214 Accounts payable, accrued expenses and other current liabilities $ 5,247 Other noncurrent liabilities 4,297 Total liabilities assumed $ 9,544 Net assets acquired $ 136,670 For the acquisition of PolSource, the estimated fair values of the assets acquired and liabilities assumed are provisional and based on the information that was available as of the acquisition date. The Company expects to complete the purchase price allocations as soon as practicable but no later than one year from the acquisition date. As of June 30, 2021, the following table presents the estimated fair values and useful lives of intangible assets acquired from PolSource: PolSource Weighted Average Useful Life (in years) Amount Customer relationships 6 $ 14,390 Trade names 3 900 Total $ 15,290 The goodwill recognized as a result of the PolSource acquisition is attributable to synergies expected to be achieved by combining the businesses of EPAM and PolSource, expected future contracts, the assembled workforce acquired and other factors. This goodwill is not expected to be deductible for income tax purposes . Revenues generated by PolSource included in the Company’s consolidated statements of income totaled $16.6 million during the three and six months ended June 30, 2021. The Company recognized acquisition-related costs associated with the PolSource acquisition during the three and six months ended June 30, 2021 totaling $0.4 million and $1.4 million, respectively. These costs are included in Selling, general and administrative expenses in the accompanying consolidated statements of income. Pro forma results of operations have not been presented because the effect of the acquisition of PolSource and its subsidiaries on the Company’s condensed consolidated financial statements was not material. Other 2021 Acquisitions — During the three months ended June 30, 2021, the Company completed two additional acquisitions with an aggregate purchase price of $17.1 million including contingent consideration with an acquisition-date fair value of $3.4 million. The Company could pay up to $10.8 million in contingent consideration and the actual future payout is subject to attainment of specified performance targets during the periods ranging from 12 months to 24 months after the respective acquisition dates. These acquisitions increased EPAM’s e-platform offerings and expanded the Company’s geographical reach, as well as added $5.1 million in intangible assets, consisting mainly of customer relationships. Revenues generated by these Other 2021 acquisitions totaled $2.0 million during the three months ended June 30, 2021. Pro forma results of operations have not been presented because the effect of these acquisitions on the Company’s consolidated financial statements was not material individually or in the aggregate.

GOODWILL

GOODWILL	6 Months Ended
	Jun. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL	GOODWILL Goodwill by reportable segment was as follows: North America Europe Russia Total Balance as of January 1, 2021 $ 121,132 $ 90,106 $ 718 $ 211,956 PolSource acquisition 68,117 45,411 — 113,528 Other 2021 acquisitions 4,609 5,716 — 10,325 2020 acquisitions purchase accounting adjustments — (24) — (24) Effect of net foreign currency exchange rate changes (146) (166) 4 (308) Balance as of June 30, 2021 $ 193,712 $ 141,043 $ 722 $ 335,477

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	6 Months Ended
	Jun. 30, 2021
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS The Company carries certain assets and liabilities at fair value on a recurring basis on its consolidated balance sheets. The following tables present the fair values of the Company’s financial assets and liabilities measured at fair value on a recurring basis as of June 30, 2021 and December 31, 2020: As of June 30, 2021 Balance Level 1 Level 2 Level 3 Foreign exchange derivative assets $ 3,049 $ — $ 3,049 $ — Total assets measured at fair value on a recurring basis $ 3,049 $ — $ 3,049 $ — Foreign exchange derivative liabilities $ 975 $ — $ 975 $ — Contingent consideration 29,167 — — 29,167 Total liabilities measured at fair value on a recurring basis $ 30,142 $ — $ 975 $ 29,167 As of December 31, 2020 Balance Level 1 Level 2 Level 3 Foreign exchange derivative assets $ 4,955 $ — $ 4,955 $ — Total assets measured at fair value on a recurring basis $ 4,955 $ — $ 4,955 $ — Foreign exchange derivative liabilities $ 243 $ — $ 243 $ — Contingent consideration 7,470 — — 7,470 Total liabilities measured at fair value on a recurring basis $ 7,713 $ — $ 243 $ 7,470 The foreign exchange derivatives are valued using pricing models and discounted cash flow methodologies based on observable foreign exchange data at the measurement date. See Note 5 “Derivative Financial Instruments” in the condensed consolidated interim financial statements for additional information regarding derivative financial instruments. The Company determines the fair value of the contingent consideration liabilities using Monte Carlo simulations (which involve a simulation of future revenues and earnings during the earn-out period using management's best estimates) or probability-weighted expected return methods. Changes in financial projections, market risk assumptions, discount rates or probability assumptions related to achieving the various earn-out criteria would result in a change in the fair value of contingent consideration. Such changes, if any, are recorded within Interest and other income, net in the Company’s condensed consolidated statements of income. The fair value of the contingent consideration for the PolSource acquisition attributable to future revenues and earnings was measured utilizing a Monte Carlo simulation, based on future revenue and earnings projections of the business, revenue volatility and asset volatility of comparable companies, and a discount rate. The discount rate used to determine the fair value of this contingent consideration was 0.4%. The fair value of the contingent consideration for the PolSource acquisition attributable to future operating metrics was measured using a probability-weighted expected return method, based on the expected future payments using the earnout formula and performance targets specified in the purchase agreement and adjusting those estimates to reflect the probability of their achievement. The weighted-average estimated future payments were then discounted to present value using a rate based on EPAM’s cost of debt. The discount rate used to determine the fair value of this contingent consideration was 0.4%. The fair value of the contingent consideration for all other acquisitions was determined using a probability-weighted expected return method and is based on the expected future payments to be made to the sellers of the acquired businesses in accordance with the provisions outlined in the respective purchase agreements. Although there is significant judgment involved, the Company believes its estimates and assumptions are reasonable. In determining fair value, the Company considered a variety of factors, including future performance of the acquired businesses using financial projections developed by the Company and market risk assumptions that were derived for revenue growth and earnings before interest and taxes. The Company estimated future payments using the earnout formula and performance targets specified in the purchase agreements and adjusted those estimates to reflect the probability of their achievement. Those weighted-average estimated future payments were then discounted to present value using a rate based on the weighted-average cost of capital of guideline companies. The discount rates used to determine the fair value of contingent consideration for the 2020 Acquisitions ranged from a minimum of 15.5% to a maximum of 17.5%. A reconciliation of the beginning and ending balances of Level 3 acquisition-related contingent consideration using significant unobservable inputs for the six months ended June 30, 2021 is as follows: Amount Contingent consideration liabilities as of January 1, 2021 $ 7,470 Payment of contingent consideration for previously acquired businesses (1,000) PolSource acquisition 25,000 Other 2021 acquisitions 3,366 Changes in fair value of contingent consideration included in Interest and other income, net (5,636) Effect of net foreign currency exchange rate changes (33) Contingent consideration liabilities as of June 30, 2021 $ 29,167 Financial Assets and Liabilities Not Measured at Fair Value on a Recurring Basis Estimates of fair value of financial instruments not carried at fair value on a recurring basis on the Company’s consolidated balance sheets are generally subjective in nature and are determined as of a specific point in time based on the characteristics of the financial instruments and relevant market information. The generally short maturities of certain assets and liabilities result in a number of assets and liabilities for which fair value equals or closely approximates the amount recorded on the Company’s condensed consolidated balance sheets. The following tables present the estimated fair values of the Company’s financial assets and liabilities not measured at fair value on a recurring basis as of the dates indicated: Fair Value Hierarchy Balance Estimated Fair Value Level 1 Level 2 Level 3 June 30, 2021 Financial Assets: Cash equivalents: Money market funds $ 116,212 $ 116,212 $ 116,212 $ — $ — Total cash equivalents $ 116,212 $ 116,212 $ 116,212 $ — $ — Restricted cash $ 1,816 $ 1,816 $ 1,816 $ — $ — Employee loans $ 579 $ 579 $ — $ — $ 579 Financial Liabilities: Borrowings under the 2017 Credit Facility $ 25,007 $ 25,007 $ — $ 25,007 $ — Fair Value Hierarchy Balance Estimated Fair Value Level 1 Level 2 Level 3 December 31, 2020 Financial Assets: Cash equivalents: Money market funds $ 153,783 $ 153,783 $ 153,783 $ — $ — Total cash equivalents $ 153,783 $ 153,783 $ 153,783 $ — $ — Restricted cash $ 1,390 $ 1,390 $ 1,390 $ — $ — Time deposits included in Short-term investments $ 60,007 $ 60,007 $ — $ 60,007 $ — Employee loans $ 794 $ 794 $ — $ — $ 794 Financial Liabilities: Borrowings under the 2017 Credit Facility $ 25,007 $ 25,007 $ — $ 25,007 $ — Non-Marketable Securities Without Readily Determinable Fair Values The Company holds investments in equity securities that do not have readily determinable fair values. These investments are recorded at cost and are remeasured to fair value based on certain observable price changes or impairment events as they occur. The carrying amount of these investments was $27.5 million and $25.0 million as of June 30, 2021 and December 31, 2020, respectively and is classified as Other noncurrent assets in the Company’s condensed consolidated balance sheets.

DERIVATIVE FINANCIAL INSTRUMENT

DERIVATIVE FINANCIAL INSTRUMENTS	6 Months Ended
	Jun. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVE FINANCIAL INSTRUMENTS	DERIVATIVE FINANCIAL INSTRUMENTSIn the normal course of business, the Company uses derivative financial instruments to manage the risk of fluctuations in foreign currency exchange rates. The Company has a hedging program whereby it enters into a series of foreign exchange forward contracts with durations of twelve months or less that are designated as cash flow hedges of forecasted Russian ruble, Polish zloty and Indian rupee transactions. As of June 30, 2021, all of the Company’s foreign exchange forward contracts were designated as hedges and there is no financial collateral (including cash collateral) required to be posted by the Company related to the foreign exchange forward contracts. The fair value of derivative instruments on the Company’s consolidated balance sheets as of June 30, 2021 and December 31, 2020 were as follows: As of June 30, 2021 As of December 31, 2020 Balance Sheet Classification Asset Derivatives Liability Derivatives Asset Derivatives Liability Derivatives Foreign exchange forward contracts - Prepaid expenses and other current assets $ 3,049 $ 4,955 Accrued expenses and other current liabilities $ 975 $ 243

LEASES

LEASES	6 Months Ended
	Jun. 30, 2021
Leases [Abstract]
LEASES	LEASES The Company leases office space, corporate apartments, office equipment, and vehicles. Many of the Company’s leases contain variable payments including changes in base rent and charges for common area maintenance or other miscellaneous expenses. Due to this variability, the cash flows associated with these variable payments are not included in the minimum lease payments used in determining the right-of-use assets and associated lease liabilities and are recognized in the period in which the obligation for such payments is incurred. The Company’s leases have remaining lease terms ranging from 0.1 to 9.9 years. Certain lease agreements, mainly for office space, include options to extend or terminate the lease before the expiration date. The Company considers such options when determining the lease term when it is reasonably certain that the Company will exercise that option. The Company leases and subleases a portion of its office space to third parties. Lease income and sublease income were immaterial for the three and six months ended June 30, 2021 and 2020. During the three and six months ended June 30, 2021 and 2020, the components of lease expense were as follows: Three Months Ended Six Months Ended Income Statement Classification 2021 2020 2021 2020 Operating lease cost Selling, general and administrative expenses $ 17,245 $ 18,851 $ 34,501 $ 37,714 Variable lease cost Selling, general and administrative expenses 1,656 579 3,916 3,214 Short-term lease cost Selling, general and administrative expenses 336 269 514 809 Total lease cost $ 19,237 $ 19,699 $ 38,931 $ 41,737 Supplemental cash flow information related to leases for the three and six months ended June 30, 2021 and 2020 was as follows: Three Months Ended Six Months Ended 2021 2020 2021 2020 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows used for operating leases $ 17,774 $ 16,481 $ 35,419 $ 33,372 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 1,639 $ 11,676 $ 1,677 $ 42,928 Non-cash net decrease due to lease modifications: Operating lease right-of-use assets $ (813) $ (8,566) $ (1,879) $ (3,982) Operating lease liabilities $ (813) $ (8,562) $ (1,879) $ (3,989) Weighted average remaining lease term and discount rate as of June 30, 2021 and 2020 were as follows: As of June 30, 2021 As of June 30, 2020 Weighted average remaining lease term, in years: Operating leases 5.8 6.0 Weighted average discount rate: Operating leases 2.6 % 3.2 % As of June 30, 2021, operating lease liabilities will mature as follows: Year ending December 31, Lease Payments 2021 (excluding six months ended June 30, 2021) $ 31,405 2022 47,210 2023 36,440 2024 31,115 2025 22,471 Thereafter 51,040 Total lease payments 219,681 Less: imputed interest (14,875) Total $ 204,806 The Company had committed to payments of $0.6 million related to operating lease agreements that had not yet commenced as of June 30, 2021. These operating leases will commence on various dates during 2021 with lease terms ranging from 2.0 to 2.8 years. The Company did not have any material finance lease agreements that had not yet commenced.

DEBT

DEBT	6 Months Ended
	Jun. 30, 2021
Debt Disclosure [Abstract]
DEBT	DEBT Revolving Line of Credit — On May 24, 2017, the Company entered into an unsecured credit facility (the “2017 Credit Facility”), as may be amended from time to time, with PNC Bank, National Association; PNC Capital Markets LLC; Citibank N.A.; Wells Fargo Bank, National Association; Fifth Third Bank and Santander Bank, N.A. (collectively the “Lenders”). The 2017 Credit Facility provides for a borrowing capacity of $300.0 million, with potential to increase the borrowing capacity up to $400.0 million if certain conditions are met. The 2017 Credit Facility matures on May 24, 2022. Borrowings under the 2017 Credit Facility may be denominated in U.S. dollars or up to a maximum of $100.0 million equivalent in British pounds sterling, Canadian dollars, euros or Swiss francs and other currencies as may be approved by the administrative agent and the Lenders. Borrowings under the 2017 Credit Facility bear interest at either a base rate or Euro-rate plus a margin based on the Company’s leverage ratio. The base rate is equal to the highest of (a) the Overnight Bank Funding Rate, plus 0.5%, (b) the Prime Rate, and (c) the Daily LIBOR Rate, plus 1.0%. As of June 30, 2021, the Company’s outstanding borrowings are subject to a LIBOR-based interest rate which resets regularly at issuance, based on lending terms. The 2017 Credit Facility includes customary business and financial covenants that may restrict the Company’s ability to make or pay dividends (other than certain intercompany dividends) if a potential or an actual event of default has occurred or would be triggered. As of June 30, 2021, the Company was in compliance with all covenants contained in the 2017 Credit Facility. The following table presents the outstanding debt and borrowing capacity of the Company under the 2017 Credit Facility: As of As of Outstanding debt $ 25,000 $ 25,000 Interest rate 1.1 % 1.2 % Available borrowing capacity $ 275,000 $ 275,000 Current maximum borrowing capacity $ 300,000 $ 300,000

REVENUES

REVENUES	6 Months Ended
	Jun. 30, 2021
Revenue from Contract with Customer [Abstract]
REVENUES	REVENUES Disaggregation of Revenues The following tables present the disaggregation of the Company’s revenues by customer location, including a reconciliation of the disaggregated revenues with the reportable segments (Note 13 “Segment Information”) for the periods indicated: Three Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Customer Locations North America $ 508,330 $ 18,036 $ 1,032 $ 527,398 Europe 21,615 269,596 70 291,281 CIS 1,410 — 36,293 37,703 APAC 667 24,317 — 24,984 Revenues $ 532,022 $ 311,949 $ 37,395 $ 881,366 Six Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Customer Locations North America $ 963,097 $ 32,699 $ 1,923 $ 997,719 Europe 39,370 511,150 133 550,653 CIS 3,266 14 64,557 67,837 APAC 1,142 44,790 — 45,932 Revenues $ 1,006,875 $ 588,653 $ 66,613 $ 1,662,141 Three Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Customer Locations North America $ 370,693 $ 10,835 $ 408 $ 381,936 Europe 11,195 199,866 3 211,064 CIS 2,236 4 19,838 22,078 APAC 705 16,600 — 17,305 Revenues $ 384,829 $ 227,305 $ 20,249 $ 632,383 Six Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Customer Locations North America $ 748,477 $ 21,254 $ 2,035 $ 771,766 Europe 21,527 412,588 6 434,121 CIS 4,790 16 42,132 46,938 APAC 1,137 29,780 — 30,917 Revenues $ 775,931 $ 463,638 $ 44,173 $ 1,283,742 The following tables present the disaggregation of the Company’s revenues by industry vertical, including a reconciliation of the disaggregated revenues with the reportable segments (Note 13 “Segment Information”) for the periods indicated: Three Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Industry Verticals Financial Services $ 83,342 $ 85,965 $ 24,631 $ 193,938 Travel & Consumer 85,075 79,731 6,739 171,545 Software & Hi-Tech 134,638 23,934 590 159,162 Business Information & Media 92,379 65,032 436 157,847 Life Sciences & Healthcare 80,712 10,780 204 91,696 Emerging Verticals 55,876 46,507 4,795 107,178 Revenues $ 532,022 $ 311,949 $ 37,395 $ 881,366 Six Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Industry Verticals Financial Services $ 153,082 $ 164,005 $ 45,709 $ 362,796 Travel & Consumer 154,504 144,355 11,697 310,556 Software & Hi-Tech 260,224 44,907 1,095 306,226 Business Information & Media 179,584 125,189 823 305,596 Life Sciences & Healthcare 156,301 26,131 379 182,811 Emerging Verticals 103,180 84,066 6,910 194,156 Revenues $ 1,006,875 $ 588,653 $ 66,613 $ 1,662,141 Three Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Industry Verticals Financial Services $ 47,687 $ 66,655 $ 13,633 $ 127,975 Travel & Consumer 52,193 51,253 3,824 107,270 Software & Hi-Tech 100,801 18,165 519 119,485 Business Information & Media 81,481 58,338 439 140,258 Life Sciences & Healthcare 61,776 7,069 39 68,884 Emerging Verticals 40,891 25,825 1,795 68,511 Revenues $ 384,829 $ 227,305 $ 20,249 $ 632,383 Six Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Industry Verticals Financial Services $ 95,555 $ 134,249 $ 29,814 $ 259,618 Travel & Consumer 106,917 112,320 7,563 226,800 Software & Hi-Tech 202,538 36,311 2,485 241,334 Business Information & Media 161,701 116,484 799 278,984 Life Sciences & Healthcare 123,387 14,688 48 138,123 Emerging Verticals 85,833 49,586 3,464 138,883 Revenues $ 775,931 $ 463,638 $ 44,173 $ 1,283,742 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 13 “Segment Information”) for the periods indicated: Three Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Contract Types Time-and-material $ 466,204 $ 267,070 $ 19,239 $ 752,513 Fixed-price 61,383 44,252 18,115 123,750 Licensing 4,076 260 31 4,367 Other revenues 359 367 10 736 Revenues $ 532,022 $ 311,949 $ 37,395 $ 881,366 Six Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Contract Types Time-and-material $ 884,091 $ 499,761 $ 33,666 $ 1,417,518 Fixed-price 114,398 87,818 32,816 235,032 Licensing 7,611 314 112 8,037 Other revenues 775 760 19 1,554 Revenues $ 1,006,875 $ 588,653 $ 66,613 $ 1,662,141 Three Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Contract Types Time-and-material $ 348,715 $ 192,173 $ 13,972 $ 554,860 Fixed-price 33,855 32,253 6,259 72,367 Licensing 1,958 545 9 2,512 Other revenues 301 2,334 9 2,644 Revenues $ 384,829 $ 227,305 $ 20,249 $ 632,383 Six Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Contract Types Time-and-material $ 705,978 $ 382,493 $ 27,568 $ 1,116,039 Fixed-price 65,710 77,508 15,080 158,298 Licensing 3,728 707 1,467 5,902 Other revenues 515 2,930 58 3,503 Revenues $ 775,931 $ 463,638 $ 44,173 $ 1,283,742 Timing of Revenue Recognition The following tables present the timing of revenue recognition reconciled with the Company’s reportable segments (Note 13 “Segment Information”) for the periods indicated: Three Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Timing of Revenue Recognition Transferred over time $ 529,230 $ 311,840 $ 37,370 $ 878,440 Transferred at a point of time 2,792 109 25 2,926 Revenues $ 532,022 $ 311,949 $ 37,395 $ 881,366 Six Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Timing of Revenue Recognition Transferred over time $ 1,001,604 $ 588,571 $ 66,560 $ 1,656,735 Transferred at a point of time 5,271 82 53 5,406 Revenues $ 1,006,875 $ 588,653 $ 66,613 $ 1,662,141 Three Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Timing of Revenue Recognition Transferred over time $ 383,573 $ 227,073 $ 20,240 $ 630,886 Transferred at a point of time 1,256 232 9 1,497 Revenues $ 384,829 $ 227,305 $ 20,249 $ 632,383 Six Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Timing of Revenue Recognition Transferred over time $ 773,383 $ 463,244 $ 42,708 $ 1,279,335 Transferred at a point of time 2,548 394 1,465 4,407 Revenues $ 775,931 $ 463,638 $ 44,173 $ 1,283,742 During the three and six months ended June 30, 2021, the Company recognized $11.6 million and $16.5 million, respectively, of revenues from performance obligations satisfied in previous periods. Performance obligations satisfied in prior periods led to a reduction of $3.7 million of revenues during three months ended June 30, 2020 and an increase of $4.2 million of revenues during six months ended June 30, 2020. 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 June 30, 2021. 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 $ 21,439 $ 847 $ 145 $ — $ 22,431 The Company applies a practical expedient and does not disclose the amount of the transaction price allocated to the remaining performance obligations nor provide an explanation of when the Company expects to recognize that amount as revenue for certain variable consideration. Contract Balances The following table provides information on the classification of contract assets and liabilities in the condensed consolidated balance sheets: As of As of Contract assets included in Trade receivables and contract assets $ 29,802 $ 7,700 Contract liabilities included in Accrued expenses and other current liabilities $ 20,555 $ 17,383 Contract liabilities included in Other noncurrent liabilities $ 207 $ 94 Contract assets have increased since December 31, 2020 primarily due to contracts where the Company’s right to bill is contingent upon achievement of contractual milestones. Contract liabilities comprise amounts collected from the Company’s customers for revenues not yet earned and such amounts are anticipated to be recorded as revenues when services are performed in subsequent periods. Contract liabilities have increased since December 31, 2020 due to an increase in advance payments from customers for professional services and licenses during the quarter. During the three and six months ended June 30, 2021, the Company recognized $3.3 million and $14.3 million, respectively, of revenues that were included in Accrued expenses and other current liabilities at December 31, 2020. During the three and six months ended June 30, 2020, the Company recognized $1.3 million and $7.9 million, respectively, of revenues that were included in Accrued expenses and other current liabilities at December 31, 2019.

STOCK-BASED COMPENSATION

STOCK-BASED COMPENSATION	6 Months Ended
	Jun. 30, 2021
Share-based Payment Arrangement [Abstract]
STOCK-BASED COMPENSATION	STOCK-BASED COMPENSATION The following table summarizes the components of stock-based compensation expense recognized in the Company’s condensed consolidated statements of income for the periods indicated: Three Months Ended Six Months Ended 2021 2020 2021 2020 Cost of revenues (exclusive of depreciation and amortization) $ 11,261 $ 8,958 $ 22,378 $ 12,942 Selling, general and administrative expenses 12,637 10,481 26,073 18,378 Total $ 23,898 $ 19,439 $ 48,451 $ 31,320 Stock Options Stock option activity under the Company’s plans is set forth below: Number of Weighted Average Aggregate Weighted Average Options outstanding at January 1, 2021 2,772 $ 61.71 Options granted 88 $ 395.53 Options exercised (328) $ 47.76 Options forfeited/cancelled (5) $ 227.25 Options outstanding at June 30, 2021 2,527 $ 74.78 $ 1,102,051 4.1 Options vested and exercisable as of June 30, 2021 2,217 $ 52.50 $ 1,016,268 3.5 Options expected to vest as of June 30, 2021 286 $ 232.06 $ 79,898 8.6 As of June 30, 2021, $22.3 million of total remaining unrecognized stock-based compensation cost related to unvested stock options, net of estimated forfeitures, is expected to be recognized over the weighted-average remaining requisite service period of 3.0 years. Restricted Stock and Restricted Stock Units Service-Based Awards The table below summarizes activity related to the Company’s equity-classified and liability-classified service-based awards for the six months ended June 30, 2021: Equity-Classified Restricted Stock Equity-Classified Equity-Settled Restricted Stock Units Liability-Classified Cash-Settled Restricted Stock Units Number of Shares Weighted Average Grant Date Number of Shares Weighted Average Grant Date Number of Shares Weighted Average Grant Date Unvested service-based awards outstanding at January 1, 2021 9 $ 167.18 686 $ 162.15 175 $ 141.16 Awards granted — $ — 200 $ 397.62 26 $ 387.84 Awards vested — $ — (268) $ 131.85 (83) $ 116.11 Awards forfeited/cancelled — $ — (18) $ 228.28 (2) $ 221.69 Unvested service-based awards outstanding at June 30, 2021 9 $ 167.18 600 $ 252.09 116 $ 213.00 As of June 30, 2021, $0.6 million of total remaining unrecognized stock-based compensation cost related to service-based equity-classified restricted stock is expected to be recognized over the weighted-average remaining requisite service period of 1.2 years. As of June 30, 2021, $121.8 million of total remaining unrecognized stock-based compensation cost related to service-based equity-classified restricted stock units (“RSUs”), net of estimated forfeitures, is expected to be recognized over the weighted-average remaining requisite service period of 3.0 years. During the second quarter of 2021, the Company granted 17 thousand service-based equity-classified RSUs in connection with the PolSource acquisition and 11 thousand service-based equity-classified RSUs in connection with the Other 2021 acquisitions. See Note 2 “Acquisitions” in the condensed consolidated interim financial statements for additional information regarding business acquisitions. As of June 30, 2021, $41.0 million of total remaining unrecognized stock-based compensation cost related to service-based liability-classified cash-settled RSUs, net of estimated forfeitures, is expected to be recognized over the weighted-average remaining requisite service period of 2.5 years. The liability associated with the service-based liability-classified RSUs as of June 30, 2021 and December 31, 2020, was $13.3 million and $26.8 million, respectively, and was classified as Accrued compensation and benefits expenses in the condensed consolidated balance sheets. Performance-Based Awards The table below summarizes activity related to the Company’s equity-classified performance-based awards for the six months ended June 30, 2021: Equity-Classified Equity-Settled Restricted Stock Equity-Classified Equity-Settled Restricted Stock Units Number of Shares Weighted Average Grant Date Number of Shares Weighted Average Grant Date Unvested performance-based awards outstanding at January 1, 2021 9 $ 165.87 21 $ 227.16 Awards granted — $ — 1 $ 399.99 Unvested performance-based awards outstanding at June 30, 2021 9 $ 165.87 22 $ 233.43 As of June 30, 2021, $0.8 million of total remaining unrecognized stock-based compensation cost related to performance-based equity-classified restricted stock is expected to be recognized over the weighted-average remaining requisite service period of 2.2 years. As of June 30, 2021, $2.8 million of total remaining unrecognized stock-based compensation cost related to performance-based equity-classified RSUs is expected to be recognized over the weighted-average remaining requisite service period of 2.2 years. During the second quarter of 2021, in connection with the PolSource acquisition, the Company granted 1 thousand performance-based equity-settled RSUs. Vesting of these performance-based equity-settled RSUs is dependent on continued service and achievement of certain revenue, earnings and operational targets. Additionally, during the second quarter of 2021, the Company issued certain performance-based equity-settled RSUs with undetermined conditions for future vesting, which are not deemed granted and outstanding for accounting purposes, and therefore they have been excluded from the awards granted disclosure and recognized expense for the period presented. The Company issued 5 thousand of such performance-based equity-settled RSUs in connection with the PolSource acquisition and 1 thousand of such performance-based equity-settled RSUs in connection with the Other 2021 Acquisitions. See Note 2 “Acquisitions” in the condensed consolidated interim financial statements for additional information regarding business acquisitions. As of June 30, 2021, the Company has committed to issuing 17 thousand RSUs to employees of PolSource and 1 thousand RSUs as well as future RSU awards valued at $3.8 million to employees of Other 2021 Acquisitions at various dates over the next 12 months . As of June 30, 2021, these awards were not considered granted for accounting purposes.

INCOME TAXES

INCOME TAXES	6 Months Ended
	Jun. 30, 2021
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES In determining its interim provision for income taxes, the Company uses an estimated annual effective tax rate, which is based on expected annual profit before tax, statutory tax rates and tax planning opportunities available in the various jurisdictions in which the Company operates. Certain significant or unusual items are separately recognized in the quarter in which they occur and can be a source of variability in the effective tax rates from quarter to quarter. The Company’s worldwide effective tax rates for the three months ended June 30, 2021 and 2020 were 6.9% and 12.4%, respectively, and 6.0% and 11.8% during the six months ended June 30, 2021 and 2020, respectively. The Company’s effective tax rates benefited from excess tax benefits recorded upon vesting or exercise of stock-based awards of $21.0 million and $8.1 million during the three months ended June 30, 2021 and 2020, respectively, and $42.5 million and $19.8 million during the six months ended June 30, 2021 and 2020, respectively.

EARNINGS PER SHARE

EARNINGS PER SHARE	6 Months Ended
	Jun. 30, 2021
Earnings Per Share [Abstract]
EARNINGS PER SHARE	EARNINGS PER SHARE Basic earnings per share is computed by dividing net income available to common shareholders by the weighted-average number of shares of common stock outstanding during the period. For purposes of computing basic earnings per share, any nonvested shares of restricted stock that have been issued by the Company and are contingently returnable to the Company are excluded from the weighted-average number of shares of common stock outstanding during the period. Diluted earnings per share is computed by dividing net income available to common shareholders by the weighted-average number of shares of common stock outstanding during the period increased to include the number of additional shares of common stock that would have been outstanding if the potentially dilutive securities had been issued. Potentially dilutive securities include outstanding stock options, unvested restricted stock and unvested equity-settled RSUs. The dilutive effect of potentially dilutive securities is reflected in diluted earnings per share by application of the treasury stock method. The following table sets forth the computation of basic and diluted earnings per share of common stock as follows: Three Months Ended Six Months Ended 2021 2020 2021 2020 Numerator for basic and diluted earnings per share: Net income $ 114,671 $ 66,624 $ 223,717 $ 152,189 Numerator for basic and diluted earnings per share $ 114,671 $ 66,624 $ 223,717 $ 152,189 Denominator: Weighted average common shares for basic earnings per share 56,463 55,701 56,317 55,494 Net effect of dilutive stock options, restricted stock units and restricted stock awards 2,548 2,545 2,579 2,700 Weighted average common shares for diluted earnings per share 59,011 58,246 58,896 58,194 Net income per share: Basic $ 2.03 $ 1.20 $ 3.97 $ 2.74 Diluted $ 1.94 $ 1.14 $ 3.80 $ 2.62 The number of shares underlying equity-based awards that were excluded from the calculation of diluted earnings per share as their effect would be anti-dilutive was 83 thousand and 49 thousand during the three and six months ended June 30, 2021, respectively. The number of shares underlying equity-based awards that were excluded from the calculation of diluted earnings per share as their effect would be anti-dilutive was 147 thousand and 78 thousand during the three and six months ended June 30, 2020, respectively.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	6 Months Ended
	Jun. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Indemnification Obligations — In the normal course of business, the Company is a party to a variety of agreements under which it may be obligated to indemnify the other party for certain matters. These obligations typically arise in contracts where the Company customarily agrees to hold the other party harmless against losses arising from a breach of representations or covenants for certain matters, infringement of third party intellectual property rights, data privacy violations, and certain tortious conduct in the course of providing services. The duration of these indemnifications varies, and in certain cases, is indefinite. The Company is unable to reasonably estimate the maximum potential amount of future payments under these or similar agreements due to the unique facts and circumstances of each agreement and the fact that certain indemnifications provide for no limitation to the maximum potential future payments under the indemnification. Management is not aware of any such matters that would have a material effect on the condensed consolidated financial statements of the Company. Litigation — From time to time, the Company is involved in litigation, claims or other contingencies arising in the ordinary course of business. The Company accrues a liability when a loss is considered probable and the amount can be reasonably estimated. When a material loss contingency is reasonably possible but not probable, the Company does not record a liability, but instead discloses the nature and the amount of the claim, and an estimate of the loss or range of loss, if such an estimate can be made. Legal fees are expensed as incurred. In the opinion of management, the outcome of any existing claims and legal or regulatory proceedings, if decided adversely, is not expected to have a material effect on the Company’s business, financial condition, results of operations or cash flows.

SEGMENT INFORMATION

SEGMENT INFORMATION	6 Months Ended
	Jun. 30, 2021
Segment Reporting [Abstract]
SEGMENT INFORMATION	SEGMENT INFORMATION The Company determines its business segments and reports segment information in accordance with how the Company’s chief operating decision maker (“CODM”) organizes the segments to evaluate performance, allocate resources and make business decisions. Segment results are based on the segment’s revenues and operating profit, where segment operating profit is defined as income from operations before unallocated costs. Expenses included in segment operating profit consist principally of direct selling and delivery costs as well as an allocation of certain shared services expenses. Certain corporate expenses are not allocated to specific segments as these expenses are not controllable at the segment level. Such expenses include certain types of professional fees, non-corporate taxes, compensation to non-employee directors and certain other general and administrative expenses, including compensation of specific groups of non-production employees. In addition, the Company does not allocate amortization of intangible assets acquired through business combinations, goodwill and other asset impairment charges, stock-based compensation expenses, acquisition-related costs and certain other one-time charges. These unallocated amounts are combined with total segment operating profit to arrive at consolidated income from operations as reported below in the reconciliation of segment operating profit to consolidated income before provision for income taxes. Additionally, management has determined that it is not practical to allocate identifiable assets by segment since such assets are used interchangeably among the segments. The Company manages its business primarily based on the managerial responsibility for its client base and market. As managerial responsibility for a particular customer relationship generally correlates with the customer’s geographic location, there is a high degree of similarity between customer locations and the geographic boundaries of the Company’s reportable segments. In some cases, managerial responsibility for a particular customer is assigned to a management team in another region and is usually based on the strength of the relationship between customer executives and particular members of EPAM’s senior management team. In such cases, the customer’s activity would be reported through the management team’s reportable segment. Revenues from external customers and operating profit/(loss), before unallocated expenses, by reportable segment for the three and six months ended June 30, 2021 and 2020, were as follows: Three Months Ended Six Months Ended 2021 2020 2021 2020 Segment revenues: North America $ 532,022 $ 384,829 $ 1,006,875 $ 775,931 Europe 311,949 227,305 588,653 463,638 Russia 37,395 20,249 66,613 44,173 Total segment revenues $ 881,366 $ 632,383 $ 1,662,141 $ 1,283,742 Segment operating profit/(loss): North America $ 111,260 $ 82,752 $ 205,363 $ 161,679 Europe 50,452 34,426 101,525 66,205 Russia 6,029 (5,645) 7,008 (5,126) Total segment operating profit $ 167,741 $ 111,533 $ 313,896 $ 222,758 Intersegment transactions were excluded from the above on the basis that they are neither included in the measure of a segment’s profit and loss results, nor considered by the CODM during the review of segment results. There were no customers that accounted for more than 10% of total segment revenues during the three and six months ended June 30, 2021 and 2020. Reconciliation of segment operating profit to consolidated income before provision for income taxes is presented below: Three Months Ended Six Months Ended 2021 2020 2021 2020 Total segment operating profit: $ 167,741 $ 111,533 $ 313,896 $ 222,758 Unallocated amounts: Stock-based compensation expense (23,898) (19,439) (48,451) (31,320) Amortization of intangibles assets (3,961) (2,994) (7,101) (6,129) Other acquisition-related expenses (2,099) (148) (4,032) (616) Other unallocated expenses (12,509) (5,526) (21,787) (13,758) Income from operations 125,274 83,426 232,525 170,935 Interest and other income, net 2,580 1,817 7,954 4,203 Foreign exchange loss (4,693) (9,167) (2,394) (2,643) Income before provision for income taxes $ 123,161 $ 76,076 $ 238,085 $ 172,495 Geographic Area Information Long-lived assets include property and equipment, net of accumulated depreciation and amortization, and management has determined that it is not practical to allocate these assets by segment since such assets are used interchangeably among the segments. Physical locations and values of the Company’s long-lived assets are presented below: As of As of Belarus $ 77,969 $ 73,988 Ukraine 27,411 30,980 Russia 15,506 15,036 United States 15,147 15,718 India 7,195 7,079 Hungary 6,112 5,365 Poland 5,704 5,434 Spain 2,828 2,799 Mexico 2,656 2,419 China 2,323 2,722 Other 10,694 7,993 Total $ 173,545 $ 169,533 The table below presents information about the Company’s revenues by customer location for the three and six months ended June 30, 2021 and 2020: Three Months Ended Six Months Ended 2021 2020 2021 2020 United States $ 502,499 $ 365,004 $ 950,520 $ 735,093 United Kingdom 112,739 82,277 206,203 174,409 Switzerland 63,794 46,537 131,362 93,759 Netherlands 36,700 27,237 69,732 53,146 Russia 35,767 19,448 63,423 41,409 Germany 25,736 19,798 47,761 39,991 Canada 24,455 16,585 46,290 34,505 Other locations 79,676 55,497 146,850 111,430 Total $ 881,366 $ 632,383 $ 1,662,141 $ 1,283,742

ACCUMULATED OTHER COMPREHENSIVE

ACCUMULATED OTHER COMPREHENSIVE LOSS	6 Months Ended
	Jun. 30, 2021
Equity [Abstract]
ACCUMULATED OTHER COMPREHENSIVE LOSS	ACCUMULATED OTHER COMPREHENSIVE LOSS The following table summarizes the changes in the accumulated balances for each component of accumulated other comprehensive loss: Three Months Ended Six Months Ended 2021 2020 2021 2020 Foreign currency translation Beginning balance $ (38,699) $ (61,185) $ (28,168) $ (32,666) Foreign currency translation 12,088 15,932 (1,493) (19,400) Income tax (expense)/benefit (2,451) (3,490) 599 3,323 Foreign currency translation, net of tax 9,637 12,442 (894) (16,077) Ending balance $ (29,062) $ (48,743) $ (29,062) $ (48,743) Cash flow hedging instruments Beginning balance $ (439) $ (8,076) $ 3,642 $ 1,292 Unrealized gain/(loss) in fair value 1,271 10,168 (6,075) (1,260) Net gain/(loss) reclassified into Cost of revenues (exclusive of depreciation and amortization) 1,371 (1,851) 3,437 (2,511) Income tax (expense)/benefit (602) (1,871) 597 849 Cash flow hedging instruments, net of tax 2,040 6,446 (2,041) (2,922) Ending balance (1) $ 1,601 $ (1,630) $ 1,601 $ (1,630) Defined benefit plans Beginning balance $ (1,612) $ — $ (986) $ — Actuarial losses — — (811) — Income tax benefit — — 185 — Defined benefit plans, net of tax — — (626) — Ending balance $ (1,612) $ — $ (1,612) $ — Accumulated other comprehensive loss $ (29,073) $ (50,373) $ (29,073) $ (50,373)

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	6 Months Ended
	Jun. 30, 2021
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS Subsequent to June 30, 2021, the Company completed two additional acquisitions. In aggregate, the Company paid approximately $53.7 million in cash at closing, agreed to pay up to $10.8 million in deferred cash consideration, as well as up to $18.2 million in cash earn-out consideration and up to $12.0 million in restricted stock earn-out consideration based on the achievement of certain revenue, earnings and operational targets payable at various times through the fourth anniversary of the acquisition date. In addition, the Company agreed to grant performance-based RSUs valued at up to $35.3 million for which payout is dependent on the achievement of certain revenue, earnings and operational targets through December 31, 2024 and service-based RSUs valued at approximately $2.3 million to employees of the acquired companies. Due to the timing of the acquisitions, the initial accounting for the acquisitions is incomplete. As such, the Company is not able to disclose certain information relating to the acquisitions, including the preliminary fair value of assets acquired and liabilities assumed. The Company expects to complete the initial accounting for these acquisitions during the third quarter of 2021.

BUSINESS AND SUMMARY OF SIGNI_2

BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	6 Months Ended
	Jun. 30, 2021
Accounting Policies [Abstract]
Nature of Operations	EPAM Systems, Inc. (the “Company” or “EPAM”) is a leading global provider of digital platform engineering and software development services to customers located around the world, primarily in North America, Europe, Asia and Australia. The Company’s industry expertise includes financial services, travel and consumer, software and hi-tech, business information and media, life sciences and healthcare, as well as other emerging industries. The Company is incorporated in Delaware with headquarters in Newtown, Pennsylvania.
Basis of Presentation	Basis of Presentation — The accompanying unaudited condensed consolidated financial statements of EPAM have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP” or “U.S. GAAP”) and Article 10 of Regulation S-X under the Securities Exchange Act of 1934, as amended. The unaudited condensed consolidated financial statements include the financial statements of EPAM Systems, Inc. and its subsidiaries with all intercompany balances and transactions eliminated.
Use of Estimates	The preparation of these condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in these condensed consolidated financial statements and accompanying notes. Actual results could differ from those estimates, and such differences may be material to the condensed consolidated financial statements. Operating results for the interim periods are not necessarily indicative of results that may be expected to occur for the entire year. In management’s opinion, all adjustments considered necessary for a fair presentation of the accompanying unaudited condensed consolidated financial statements have been included, and all adjustments are of a normal and recurring nature.
Adoption of New Accounting Standards and Pending Accounting Standards	Adoption of New Accounting Standards The adoption of new accounting standards did not have a material impact on the Company’s consolidated financial position, results of operations, changes in stockholders’ equity and cash flows. Pending Accounting Standards From time to time, new accounting pronouncements are issued by the FASB or other standards-setting bodies that the Company will adopt according to the various timetables the FASB specifies. The Company believes the impact of recently issued standards that are not yet effective will not have a material impact on its consolidated financial position, results of operations and cash flows upon adoption.
Fair Value of Financial Instruments	The foreign exchange derivatives are valued using pricing models and discounted cash flow methodologies based on observable foreign exchange data at the measurement date. See Note 5 “Derivative Financial Instruments” in the condensed consolidated interim financial statements for additional information regarding derivative financial instruments. The Company determines the fair value of the contingent consideration liabilities using Monte Carlo simulations (which involve a simulation of future revenues and earnings during the earn-out period using management's best estimates) or probability-weighted expected return methods. Changes in financial projections, market risk assumptions, discount rates or probability assumptions related to achieving the various earn-out criteria would result in a change in the fair value of contingent consideration. Such changes, if any, are recorded within Interest and other income, net in the Company’s condensed consolidated statements of income. The fair value of the contingent consideration for the PolSource acquisition attributable to future revenues and earnings was measured utilizing a Monte Carlo simulation, based on future revenue and earnings projections of the business, revenue volatility and asset volatility of comparable companies, and a discount rate. The discount rate used to determine the fair value of this contingent consideration was 0.4%. The fair value of the contingent consideration for the PolSource acquisition attributable to future operating metrics was measured using a probability-weighted expected return method, based on the expected future payments using the earnout formula and performance targets specified in the purchase agreement and adjusting those estimates to reflect the probability of their achievement. The weighted-average estimated future payments were then discounted to present value using a rate based on EPAM’s cost of debt. The discount rate used to determine the fair value of this contingent consideration was 0.4%.
Equity Securities without Readily Determinable Fair Value	The Company holds investments in equity securities that do not have readily determinable fair values. These investments are recorded at cost and are remeasured to fair value based on certain observable price changes or impairment events as they occur. The carrying amount of these investments was $27.5 million and $25.0 million as of June 30, 2021 and December 31, 2020, respectively and is classified as Other noncurrent assets in the Company’s condensed consolidated balance sheets.
Income Taxes	In determining its interim provision for income taxes, the Company uses an estimated annual effective tax rate, which is based on expected annual profit before tax, statutory tax rates and tax planning opportunities available in the various jurisdictions in which the Company operates. Certain significant or unusual items are separately recognized in the quarter in which they occur and can be a source of variability in the effective tax rates from quarter to quarter.

ACQUISITIONS - The Estimated Fa

ACQUISITIONS - The Estimated Fair Value of the Assets Acquired and Liabilities Assumed (Tables)	6 Months Ended
	Jun. 30, 2021
Business Combination and Asset Acquisition [Abstract]
Fair Value of the Assets Acquired and Liabilities Assumed	The following table summarizes the estimated fair values of the assets acquired and liabilities assumed as of the date of acquisition for PolSource: PolSource Cash and cash equivalents $ 2,565 Trade receivables and contract assets 13,653 Prepaid and other current assets 756 Goodwill 113,528 Intangible assets 15,290 Property and equipment and other noncurrent assets 422 Total assets acquired $ 146,214 Accounts payable, accrued expenses and other current liabilities $ 5,247 Other noncurrent liabilities 4,297 Total liabilities assumed $ 9,544 Net assets acquired $ 136,670
Schedule of Acquired Finite-Lived Intangible Assets by Major Class	As of June 30, 2021, the following table presents the estimated fair values and useful lives of intangible assets acquired from PolSource: PolSource Weighted Average Useful Life (in years) Amount Customer relationships 6 $ 14,390 Trade names 3 900 Total $ 15,290

GOODWILL (Tables)

GOODWILL (Tables)	6 Months Ended
	Jun. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill By Reportable Segment	Goodwill by reportable segment was as follows: North America Europe Russia Total Balance as of January 1, 2021 $ 121,132 $ 90,106 $ 718 $ 211,956 PolSource acquisition 68,117 45,411 — 113,528 Other 2021 acquisitions 4,609 5,716 — 10,325 2020 acquisitions purchase accounting adjustments — (24) — (24) Effect of net foreign currency exchange rate changes (146) (166) 4 (308) Balance as of June 30, 2021 $ 193,712 $ 141,043 $ 722 $ 335,477

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	6 Months Ended
	Jun. 30, 2021
Fair Value Disclosures [Abstract]
Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following tables present the fair values of the Company’s financial assets and liabilities measured at fair value on a recurring basis as of June 30, 2021 and December 31, 2020: As of June 30, 2021 Balance Level 1 Level 2 Level 3 Foreign exchange derivative assets $ 3,049 $ — $ 3,049 $ — Total assets measured at fair value on a recurring basis $ 3,049 $ — $ 3,049 $ — Foreign exchange derivative liabilities $ 975 $ — $ 975 $ — Contingent consideration 29,167 — — 29,167 Total liabilities measured at fair value on a recurring basis $ 30,142 $ — $ 975 $ 29,167 As of December 31, 2020 Balance Level 1 Level 2 Level 3 Foreign exchange derivative assets $ 4,955 $ — $ 4,955 $ — Total assets measured at fair value on a recurring basis $ 4,955 $ — $ 4,955 $ — Foreign exchange derivative liabilities $ 243 $ — $ 243 $ — Contingent consideration 7,470 — — 7,470 Total liabilities measured at fair value on a recurring basis $ 7,713 $ — $ 243 $ 7,470
Acquisition-Related Contingent Consideration Roll Forward	A reconciliation of the beginning and ending balances of Level 3 acquisition-related contingent consideration using significant unobservable inputs for the six months ended June 30, 2021 is as follows: Amount Contingent consideration liabilities as of January 1, 2021 $ 7,470 Payment of contingent consideration for previously acquired businesses (1,000) PolSource acquisition 25,000 Other 2021 acquisitions 3,366 Changes in fair value of contingent consideration included in Interest and other income, net (5,636) Effect of net foreign currency exchange rate changes (33) Contingent consideration liabilities as of June 30, 2021 $ 29,167
Estimated Fair Values of Financial Assets and Liabilities not Measured at Fair Value on Recurring Basis	The following tables present the estimated fair values of the Company’s financial assets and liabilities not measured at fair value on a recurring basis as of the dates indicated: Fair Value Hierarchy Balance Estimated Fair Value Level 1 Level 2 Level 3 June 30, 2021 Financial Assets: Cash equivalents: Money market funds $ 116,212 $ 116,212 $ 116,212 $ — $ — Total cash equivalents $ 116,212 $ 116,212 $ 116,212 $ — $ — Restricted cash $ 1,816 $ 1,816 $ 1,816 $ — $ — Employee loans $ 579 $ 579 $ — $ — $ 579 Financial Liabilities: Borrowings under the 2017 Credit Facility $ 25,007 $ 25,007 $ — $ 25,007 $ — Fair Value Hierarchy Balance Estimated Fair Value Level 1 Level 2 Level 3 December 31, 2020 Financial Assets: Cash equivalents: Money market funds $ 153,783 $ 153,783 $ 153,783 $ — $ — Total cash equivalents $ 153,783 $ 153,783 $ 153,783 $ — $ — Restricted cash $ 1,390 $ 1,390 $ 1,390 $ — $ — Time deposits included in Short-term investments $ 60,007 $ 60,007 $ — $ 60,007 $ — Employee loans $ 794 $ 794 $ — $ — $ 794 Financial Liabilities: Borrowings under the 2017 Credit Facility $ 25,007 $ 25,007 $ — $ 25,007 $ —

DERIVATIVE FINANCIAL INSTRUME_2

DERIVATIVE FINANCIAL INSTRUMENTS (Tables)	6 Months Ended
	Jun. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair Value of Derivative Instruments	The fair value of derivative instruments on the Company’s consolidated balance sheets as of June 30, 2021 and December 31, 2020 were as follows: As of June 30, 2021 As of December 31, 2020 Balance Sheet Classification Asset Derivatives Liability Derivatives Asset Derivatives Liability Derivatives Foreign exchange forward contracts - Prepaid expenses and other current assets $ 3,049 $ 4,955 Accrued expenses and other current liabilities $ 975 $ 243

LEASES (Tables)

LEASES (Tables)	6 Months Ended
	Jun. 30, 2021
Leases [Abstract]
Components of Lease Expenses	During the three and six months ended June 30, 2021 and 2020, the components of lease expense were as follows: Three Months Ended Six Months Ended Income Statement Classification 2021 2020 2021 2020 Operating lease cost Selling, general and administrative expenses $ 17,245 $ 18,851 $ 34,501 $ 37,714 Variable lease cost Selling, general and administrative expenses 1,656 579 3,916 3,214 Short-term lease cost Selling, general and administrative expenses 336 269 514 809 Total lease cost $ 19,237 $ 19,699 $ 38,931 $ 41,737
Supplemental Cash Flow Information	Supplemental cash flow information related to leases for the three and six months ended June 30, 2021 and 2020 was as follows: Three Months Ended Six Months Ended 2021 2020 2021 2020 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows used for operating leases $ 17,774 $ 16,481 $ 35,419 $ 33,372 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 1,639 $ 11,676 $ 1,677 $ 42,928 Non-cash net decrease due to lease modifications: Operating lease right-of-use assets $ (813) $ (8,566) $ (1,879) $ (3,982) Operating lease liabilities $ (813) $ (8,562) $ (1,879) $ (3,989)
Weighted Average Lease Terms and Discount Rates	Weighted average remaining lease term and discount rate as of June 30, 2021 and 2020 were as follows: As of June 30, 2021 As of June 30, 2020 Weighted average remaining lease term, in years: Operating leases 5.8 6.0 Weighted average discount rate: Operating leases 2.6 % 3.2 %
Maturity of Operating Lease Liabilities	As of June 30, 2021, operating lease liabilities will mature as follows: Year ending December 31, Lease Payments 2021 (excluding six months ended June 30, 2021) $ 31,405 2022 47,210 2023 36,440 2024 31,115 2025 22,471 Thereafter 51,040 Total lease payments 219,681 Less: imputed interest (14,875) Total $ 204,806

DEBT (Tables)

DEBT (Tables)	6 Months Ended
	Jun. 30, 2021
Debt Disclosure [Abstract]
Outstanding Debt And Borrowing Capacity	The following table presents the outstanding debt and borrowing capacity of the Company under the 2017 Credit Facility: As of As of Outstanding debt $ 25,000 $ 25,000 Interest rate 1.1 % 1.2 % Available borrowing capacity $ 275,000 $ 275,000 Current maximum borrowing capacity $ 300,000 $ 300,000

REVENUES (Tables)

REVENUES (Tables)	6 Months Ended
	Jun. 30, 2021
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenues	The following tables present the disaggregation of the Company’s revenues by customer location, including a reconciliation of the disaggregated revenues with the reportable segments (Note 13 “Segment Information”) for the periods indicated: Three Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Customer Locations North America $ 508,330 $ 18,036 $ 1,032 $ 527,398 Europe 21,615 269,596 70 291,281 CIS 1,410 — 36,293 37,703 APAC 667 24,317 — 24,984 Revenues $ 532,022 $ 311,949 $ 37,395 $ 881,366 Six Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Customer Locations North America $ 963,097 $ 32,699 $ 1,923 $ 997,719 Europe 39,370 511,150 133 550,653 CIS 3,266 14 64,557 67,837 APAC 1,142 44,790 — 45,932 Revenues $ 1,006,875 $ 588,653 $ 66,613 $ 1,662,141 Three Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Customer Locations North America $ 370,693 $ 10,835 $ 408 $ 381,936 Europe 11,195 199,866 3 211,064 CIS 2,236 4 19,838 22,078 APAC 705 16,600 — 17,305 Revenues $ 384,829 $ 227,305 $ 20,249 $ 632,383 Six Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Customer Locations North America $ 748,477 $ 21,254 $ 2,035 $ 771,766 Europe 21,527 412,588 6 434,121 CIS 4,790 16 42,132 46,938 APAC 1,137 29,780 — 30,917 Revenues $ 775,931 $ 463,638 $ 44,173 $ 1,283,742 The following tables present the disaggregation of the Company’s revenues by industry vertical, including a reconciliation of the disaggregated revenues with the reportable segments (Note 13 “Segment Information”) for the periods indicated: Three Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Industry Verticals Financial Services $ 83,342 $ 85,965 $ 24,631 $ 193,938 Travel & Consumer 85,075 79,731 6,739 171,545 Software & Hi-Tech 134,638 23,934 590 159,162 Business Information & Media 92,379 65,032 436 157,847 Life Sciences & Healthcare 80,712 10,780 204 91,696 Emerging Verticals 55,876 46,507 4,795 107,178 Revenues $ 532,022 $ 311,949 $ 37,395 $ 881,366 Six Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Industry Verticals Financial Services $ 153,082 $ 164,005 $ 45,709 $ 362,796 Travel & Consumer 154,504 144,355 11,697 310,556 Software & Hi-Tech 260,224 44,907 1,095 306,226 Business Information & Media 179,584 125,189 823 305,596 Life Sciences & Healthcare 156,301 26,131 379 182,811 Emerging Verticals 103,180 84,066 6,910 194,156 Revenues $ 1,006,875 $ 588,653 $ 66,613 $ 1,662,141 Three Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Industry Verticals Financial Services $ 47,687 $ 66,655 $ 13,633 $ 127,975 Travel & Consumer 52,193 51,253 3,824 107,270 Software & Hi-Tech 100,801 18,165 519 119,485 Business Information & Media 81,481 58,338 439 140,258 Life Sciences & Healthcare 61,776 7,069 39 68,884 Emerging Verticals 40,891 25,825 1,795 68,511 Revenues $ 384,829 $ 227,305 $ 20,249 $ 632,383 Six Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Industry Verticals Financial Services $ 95,555 $ 134,249 $ 29,814 $ 259,618 Travel & Consumer 106,917 112,320 7,563 226,800 Software & Hi-Tech 202,538 36,311 2,485 241,334 Business Information & Media 161,701 116,484 799 278,984 Life Sciences & Healthcare 123,387 14,688 48 138,123 Emerging Verticals 85,833 49,586 3,464 138,883 Revenues $ 775,931 $ 463,638 $ 44,173 $ 1,283,742 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 13 “Segment Information”) for the periods indicated: Three Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Contract Types Time-and-material $ 466,204 $ 267,070 $ 19,239 $ 752,513 Fixed-price 61,383 44,252 18,115 123,750 Licensing 4,076 260 31 4,367 Other revenues 359 367 10 736 Revenues $ 532,022 $ 311,949 $ 37,395 $ 881,366 Six Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Contract Types Time-and-material $ 884,091 $ 499,761 $ 33,666 $ 1,417,518 Fixed-price 114,398 87,818 32,816 235,032 Licensing 7,611 314 112 8,037 Other revenues 775 760 19 1,554 Revenues $ 1,006,875 $ 588,653 $ 66,613 $ 1,662,141 Three Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Contract Types Time-and-material $ 348,715 $ 192,173 $ 13,972 $ 554,860 Fixed-price 33,855 32,253 6,259 72,367 Licensing 1,958 545 9 2,512 Other revenues 301 2,334 9 2,644 Revenues $ 384,829 $ 227,305 $ 20,249 $ 632,383 Six Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Contract Types Time-and-material $ 705,978 $ 382,493 $ 27,568 $ 1,116,039 Fixed-price 65,710 77,508 15,080 158,298 Licensing 3,728 707 1,467 5,902 Other revenues 515 2,930 58 3,503 Revenues $ 775,931 $ 463,638 $ 44,173 $ 1,283,742 Timing of Revenue Recognition The following tables present the timing of revenue recognition reconciled with the Company’s reportable segments (Note 13 “Segment Information”) for the periods indicated: Three Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Timing of Revenue Recognition Transferred over time $ 529,230 $ 311,840 $ 37,370 $ 878,440 Transferred at a point of time 2,792 109 25 2,926 Revenues $ 532,022 $ 311,949 $ 37,395 $ 881,366 Six Months Ended June 30, 2021 Reportable Segments North America Europe Russia Consolidated Revenues Timing of Revenue Recognition Transferred over time $ 1,001,604 $ 588,571 $ 66,560 $ 1,656,735 Transferred at a point of time 5,271 82 53 5,406 Revenues $ 1,006,875 $ 588,653 $ 66,613 $ 1,662,141 Three Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Timing of Revenue Recognition Transferred over time $ 383,573 $ 227,073 $ 20,240 $ 630,886 Transferred at a point of time 1,256 232 9 1,497 Revenues $ 384,829 $ 227,305 $ 20,249 $ 632,383 Six Months Ended June 30, 2020 Reportable Segments North America Europe Russia Consolidated Revenues Timing of Revenue Recognition Transferred over time $ 773,383 $ 463,244 $ 42,708 $ 1,279,335 Transferred at a point of time 2,548 394 1,465 4,407 Revenues $ 775,931 $ 463,638 $ 44,173 $ 1,283,742
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 June 30, 2021. 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 $ 21,439 $ 847 $ 145 $ — $ 22,431
Contract Balances	The following table provides information on the classification of contract assets and liabilities in the condensed consolidated balance sheets: As of As of Contract assets included in Trade receivables and contract assets $ 29,802 $ 7,700 Contract liabilities included in Accrued expenses and other current liabilities $ 20,555 $ 17,383 Contract liabilities included in Other noncurrent liabilities $ 207 $ 94

STOCK-BASED COMPENSATION (Table

STOCK-BASED COMPENSATION (Tables)	6 Months Ended
	Jun. 30, 2021
Share-based Payment Arrangement [Abstract]
Components of Stock-Based Compensation Expenses	The following table summarizes the components of stock-based compensation expense recognized in the Company’s condensed consolidated statements of income for the periods indicated: Three Months Ended Six Months Ended 2021 2020 2021 2020 Cost of revenues (exclusive of depreciation and amortization) $ 11,261 $ 8,958 $ 22,378 $ 12,942 Selling, general and administrative expenses 12,637 10,481 26,073 18,378 Total $ 23,898 $ 19,439 $ 48,451 $ 31,320
Stock Options Activity	Stock option activity under the Company’s plans is set forth below: Number of Weighted Average Aggregate Weighted Average Options outstanding at January 1, 2021 2,772 $ 61.71 Options granted 88 $ 395.53 Options exercised (328) $ 47.76 Options forfeited/cancelled (5) $ 227.25 Options outstanding at June 30, 2021 2,527 $ 74.78 $ 1,102,051 4.1 Options vested and exercisable as of June 30, 2021 2,217 $ 52.50 $ 1,016,268 3.5 Options expected to vest as of June 30, 2021 286 $ 232.06 $ 79,898 8.6
Service-Based Awards Activity	The table below summarizes activity related to the Company’s equity-classified and liability-classified service-based awards for the six months ended June 30, 2021: Equity-Classified Restricted Stock Equity-Classified Equity-Settled Restricted Stock Units Liability-Classified Cash-Settled Restricted Stock Units Number of Shares Weighted Average Grant Date Number of Shares Weighted Average Grant Date Number of Shares Weighted Average Grant Date Unvested service-based awards outstanding at January 1, 2021 9 $ 167.18 686 $ 162.15 175 $ 141.16 Awards granted — $ — 200 $ 397.62 26 $ 387.84 Awards vested — $ — (268) $ 131.85 (83) $ 116.11 Awards forfeited/cancelled — $ — (18) $ 228.28 (2) $ 221.69 Unvested service-based awards outstanding at June 30, 2021 9 $ 167.18 600 $ 252.09 116 $ 213.00
Performance-Based Awards Activity	The table below summarizes activity related to the Company’s equity-classified performance-based awards for the six months ended June 30, 2021: Equity-Classified Equity-Settled Restricted Stock Equity-Classified Equity-Settled Restricted Stock Units Number of Shares Weighted Average Grant Date Number of Shares Weighted Average Grant Date Unvested performance-based awards outstanding at January 1, 2021 9 $ 165.87 21 $ 227.16 Awards granted — $ — 1 $ 399.99 Unvested performance-based awards outstanding at June 30, 2021 9 $ 165.87 22 $ 233.43

EARNINGS PER SHARE (Tables)

EARNINGS PER SHARE (Tables)	6 Months Ended
	Jun. 30, 2021
Earnings Per Share [Abstract]
Computation of Basic and Diluted Earnings Per Share	The following table sets forth the computation of basic and diluted earnings per share of common stock as follows: Three Months Ended Six Months Ended 2021 2020 2021 2020 Numerator for basic and diluted earnings per share: Net income $ 114,671 $ 66,624 $ 223,717 $ 152,189 Numerator for basic and diluted earnings per share $ 114,671 $ 66,624 $ 223,717 $ 152,189 Denominator: Weighted average common shares for basic earnings per share 56,463 55,701 56,317 55,494 Net effect of dilutive stock options, restricted stock units and restricted stock awards 2,548 2,545 2,579 2,700 Weighted average common shares for diluted earnings per share 59,011 58,246 58,896 58,194 Net income per share: Basic $ 2.03 $ 1.20 $ 3.97 $ 2.74 Diluted $ 1.94 $ 1.14 $ 3.80 $ 2.62

SEGMENT INFORMATION (Tables)

SEGMENT INFORMATION (Tables)	6 Months Ended
	Jun. 30, 2021
Segment Reporting [Abstract]
Revenues from External Customers and Operating Profit/(Loss), Before Unallocated Expenses	Revenues from external customers and operating profit/(loss), before unallocated expenses, by reportable segment for the three and six months ended June 30, 2021 and 2020, were as follows: Three Months Ended Six Months Ended 2021 2020 2021 2020 Segment revenues: North America $ 532,022 $ 384,829 $ 1,006,875 $ 775,931 Europe 311,949 227,305 588,653 463,638 Russia 37,395 20,249 66,613 44,173 Total segment revenues $ 881,366 $ 632,383 $ 1,662,141 $ 1,283,742 Segment operating profit/(loss): North America $ 111,260 $ 82,752 $ 205,363 $ 161,679 Europe 50,452 34,426 101,525 66,205 Russia 6,029 (5,645) 7,008 (5,126) Total segment operating profit $ 167,741 $ 111,533 $ 313,896 $ 222,758
Reconciliation of Segment Operating Profit to Consolidated Income Before Provision for Income Taxes	Reconciliation of segment operating profit to consolidated income before provision for income taxes is presented below: Three Months Ended Six Months Ended 2021 2020 2021 2020 Total segment operating profit: $ 167,741 $ 111,533 $ 313,896 $ 222,758 Unallocated amounts: Stock-based compensation expense (23,898) (19,439) (48,451) (31,320) Amortization of intangibles assets (3,961) (2,994) (7,101) (6,129) Other acquisition-related expenses (2,099) (148) (4,032) (616) Other unallocated expenses (12,509) (5,526) (21,787) (13,758) Income from operations 125,274 83,426 232,525 170,935 Interest and other income, net 2,580 1,817 7,954 4,203 Foreign exchange loss (4,693) (9,167) (2,394) (2,643) Income before provision for income taxes $ 123,161 $ 76,076 $ 238,085 $ 172,495
Physical Location and Values of Long-Lived Assets	Physical locations and values of the Company’s long-lived assets are presented below: As of As of Belarus $ 77,969 $ 73,988 Ukraine 27,411 30,980 Russia 15,506 15,036 United States 15,147 15,718 India 7,195 7,079 Hungary 6,112 5,365 Poland 5,704 5,434 Spain 2,828 2,799 Mexico 2,656 2,419 China 2,323 2,722 Other 10,694 7,993 Total $ 173,545 $ 169,533
Revenues by Customer Location	The table below presents information about the Company’s revenues by customer location for the three and six months ended June 30, 2021 and 2020: Three Months Ended Six Months Ended 2021 2020 2021 2020 United States $ 502,499 $ 365,004 $ 950,520 $ 735,093 United Kingdom 112,739 82,277 206,203 174,409 Switzerland 63,794 46,537 131,362 93,759 Netherlands 36,700 27,237 69,732 53,146 Russia 35,767 19,448 63,423 41,409 Germany 25,736 19,798 47,761 39,991 Canada 24,455 16,585 46,290 34,505 Other locations 79,676 55,497 146,850 111,430 Total $ 881,366 $ 632,383 $ 1,662,141 $ 1,283,742

ACCUMULATED OTHER COMPREHENSI_2

ACCUMULATED OTHER COMPREHENSIVE LOSS (Tables)	6 Months Ended
	Jun. 30, 2021
Equity [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	The following table summarizes the changes in the accumulated balances for each component of accumulated other comprehensive loss: Three Months Ended Six Months Ended 2021 2020 2021 2020 Foreign currency translation Beginning balance $ (38,699) $ (61,185) $ (28,168) $ (32,666) Foreign currency translation 12,088 15,932 (1,493) (19,400) Income tax (expense)/benefit (2,451) (3,490) 599 3,323 Foreign currency translation, net of tax 9,637 12,442 (894) (16,077) Ending balance $ (29,062) $ (48,743) $ (29,062) $ (48,743) Cash flow hedging instruments Beginning balance $ (439) $ (8,076) $ 3,642 $ 1,292 Unrealized gain/(loss) in fair value 1,271 10,168 (6,075) (1,260) Net gain/(loss) reclassified into Cost of revenues (exclusive of depreciation and amortization) 1,371 (1,851) 3,437 (2,511) Income tax (expense)/benefit (602) (1,871) 597 849 Cash flow hedging instruments, net of tax 2,040 6,446 (2,041) (2,922) Ending balance (1) $ 1,601 $ (1,630) $ 1,601 $ (1,630) Defined benefit plans Beginning balance $ (1,612) $ — $ (986) $ — Actuarial losses — — (811) — Income tax benefit — — 185 — Defined benefit plans, net of tax — — (626) — Ending balance $ (1,612) $ — $ (1,612) $ — Accumulated other comprehensive loss $ (29,073) $ (50,373) $ (29,073) $ (50,373)

ACQUISITIONS - (Narrative) (Det

ACQUISITIONS - (Narrative) (Details) $ in Thousands	Apr. 02, 2021USD ($)	Jun. 30, 2021USD ($)	Jun. 30, 2021USD ($)	Dec. 31, 2020USD ($)business
Business Acquisition [Line Items]
Revenue of acquiree		$ 16,600	$ 16,600
Acquisition-related costs		400	1,400
PolSource S.A.
Business Acquisition [Line Items]
Percentage of voting interests acquired	100.00%
Number of specialists in acquired entity (more than)	350
Purchase price including contingent consideration	$ 136,700
Fair value of contingent consideration	25,000
Earn-out consideration based on achievements of certain revenue, earnings and operational targets (up to)	45,000
Contingent consideration fair value	45,000
Intangible assets	$ 15,290
Other 2021 acquisitions
Business Acquisition [Line Items]
Earn-out consideration based on achievements of certain revenue, earnings and operational targets (up to)		3,400	3,400
Revenue of acquiree		$ 2,000
Number of acquisitions		2
Purchase price including contingent consideration		$ 17,100	17,100
Contingent consideration fair value		3,400	3,400
Maximum amount of earnout payable		10,800	10,800
Intangible assets		$ 5,100	$ 5,100
Other 2021 acquisitions | Minimum
Business Acquisition [Line Items]
Estimated future operating results, period		12 months
Other 2021 acquisitions | Maximum
Business Acquisition [Line Items]
Estimated future operating results, period		24 months
2020 Acquisitions
Business Acquisition [Line Items]
Earn-out consideration based on achievements of certain revenue, earnings and operational targets (up to)				$ 5,300
Number of acquisitions | business				2
Purchase price including contingent consideration				$ 22,500
Contingent consideration fair value				5,300
Maximum amount of earnout payable				18,600
Intangible assets				$ 7,300

ACQUISITIONS - Estimated Fair V

ACQUISITIONS - Estimated Fair Values of the Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Apr. 02, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Goodwill	$ 335,477		$ 211,956
PolSource S.A.
Business Acquisition [Line Items]
Cash and cash equivalents		$ 2,565
Trade receivables and contract assets		13,653
Prepaid and other current assets		756
Goodwill		113,528
Intangible assets		15,290
Property and equipment and other noncurrent assets		422
Total assets acquired		146,214
Accounts payable, accrued expenses and other current liabilities		5,247
Other noncurrent liabilities		4,297
Total liabilities assumed		9,544
Net assets acquired		$ 136,670

ACQUISITIONS - Estimated Fair_2

ACQUISITIONS - Estimated Fair Values And Useful Lives Of Intangible Assets (Details) - PolSource S.A. $ in Thousands	6 Months Ended
	Jun. 30, 2021USD ($)
Business Acquisition [Line Items]
Intangible assets	$ 15,290
Customer Relationships
Business Acquisition [Line Items]
Weighted Average Useful Life (in years)	6 years
Intangible assets	$ 14,390
Trade Names
Business Acquisition [Line Items]
Weighted Average Useful Life (in years)	3 years
Intangible assets	$ 900

GOODWILL (Goodwill Roll Forward

GOODWILL (Goodwill Roll Forward) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2021USD ($)
Goodwill [Roll Forward]
Balance as of January 1, 2021	$ 211,956
2020 acquisitions purchase accounting adjustments	(24)
Effect of net foreign currency exchange rate changes	(308)
Balance as of June 30, 2021	335,477
PolSource S.A.
Goodwill [Roll Forward]
Acquisition	113,528
Other 2021 acquisitions
Goodwill [Roll Forward]
Acquisition	10,325
North America
Goodwill [Roll Forward]
Balance as of January 1, 2021	121,132
2020 acquisitions purchase accounting adjustments	0
Effect of net foreign currency exchange rate changes	(146)
Balance as of June 30, 2021	193,712
North America | PolSource S.A.
Goodwill [Roll Forward]
Acquisition	68,117
North America | Other 2021 acquisitions
Goodwill [Roll Forward]
Acquisition	4,609
Europe
Goodwill [Roll Forward]
Balance as of January 1, 2021	90,106
2020 acquisitions purchase accounting adjustments	(24)
Effect of net foreign currency exchange rate changes	(166)
Balance as of June 30, 2021	141,043
Europe | PolSource S.A.
Goodwill [Roll Forward]
Acquisition	45,411
Europe | Other 2021 acquisitions
Goodwill [Roll Forward]
Acquisition	5,716
Russia
Goodwill [Roll Forward]
Balance as of January 1, 2021	718
2020 acquisitions purchase accounting adjustments	0
Effect of net foreign currency exchange rate changes	4
Balance as of June 30, 2021	722
Russia | PolSource S.A.
Goodwill [Roll Forward]
Acquisition	0
Russia | Other 2021 acquisitions
Goodwill [Roll Forward]
Acquisition	$ 0

GOODWILL (Goodwill Accumulated

GOODWILL (Goodwill Accumulated Impairment Losses) (Details) - USD ($)	Jun. 30, 2021	Dec. 31, 2020
North America
Goodwill [Line Items]
Accumulated impairment loss	$ 0	$ 0
Europe
Goodwill [Line Items]
Accumulated impairment loss	0	0
Russia
Goodwill [Line Items]
Accumulated impairment loss	$ 2,200,000	$ 2,200,000

FAIR VALUE MEASUREMENTS (Financ

FAIR VALUE MEASUREMENTS (Financial Assets and Liabilities at Fair Value on Recurring Basis) (Details) - Recurring - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Financial Assets:
Total assets measured at fair value on a recurring basis	$ 3,049	$ 4,955
Financial Liabilities:
Contingent consideration	29,167	7,470
Total liabilities measured at fair value on a recurring basis	30,142	7,713
Foreign exchange contracts
Financial Assets:
Foreign exchange derivative assets	3,049	4,955
Financial Liabilities:
Foreign exchange derivative liabilities	975	243
Level 1
Financial Assets:
Total assets measured at fair value on a recurring basis	0	0
Financial Liabilities:
Contingent consideration	0	0
Total liabilities measured at fair value on a recurring basis	0	0
Level 1 | Foreign exchange contracts
Financial Assets:
Foreign exchange derivative assets	0	0
Financial Liabilities:
Foreign exchange derivative liabilities	0	0
Level 2
Financial Assets:
Total assets measured at fair value on a recurring basis	3,049	4,955
Financial Liabilities:
Contingent consideration	0	0
Total liabilities measured at fair value on a recurring basis	975	243
Level 2 | Foreign exchange contracts
Financial Assets:
Foreign exchange derivative assets	3,049	4,955
Financial Liabilities:
Foreign exchange derivative liabilities	975	243
Level 3
Financial Assets:
Total assets measured at fair value on a recurring basis	0	0
Financial Liabilities:
Contingent consideration	29,167	7,470
Total liabilities measured at fair value on a recurring basis	29,167	7,470
Level 3 | Foreign exchange contracts
Financial Assets:
Foreign exchange derivative assets	0	0
Financial Liabilities:
Foreign exchange derivative liabilities	$ 0	$ 0

FAIR VALUE MEASUREMENTS (Acquis

FAIR VALUE MEASUREMENTS (Acquisition-Related Contingent Consideration Roll Forward) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2021USD ($)	Mar. 31, 2021
Discount rate | PolSource S.A.
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Measurement input to determine fair value of contingent consideration		0.004
Discount rate | 2020 Acquisitions | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Measurement input to determine fair value of contingent consideration	0.155
Discount rate | 2020 Acquisitions | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Measurement input to determine fair value of contingent consideration	0.175
Level 3
Amount
Contingent consideration liabilities as of January 1, 2021	$ 7,470
Payment of contingent consideration for previously acquired businesses	(1,000)
Effect of net foreign currency exchange rate changes	(33)
Contingent consideration liabilities as of June 30, 2021	29,167
Level 3 | Interest and other income, net
Amount
Changes in fair value of contingent consideration included in Interest and other income, net	(5,636)
Level 3 | PolSource S.A.
Amount
Acquisition	25,000
Level 3 | Other 2021 acquisitions
Amount
Acquisition	$ 3,366

FAIR VALUE MEASUREMENTS (Estima

FAIR VALUE MEASUREMENTS (Estimated Fair Values of the Financial Assets and Liabilities not Measured at Fair Value on a Recurring Basis) (Details) - Recurring - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Balance
Financial Assets:
Cash equivalents:	$ 116,212	$ 153,783
Restricted cash	1,816	1,390
Employee loans	579	794
Balance | Money market funds
Financial Assets:
Cash equivalents:	116,212	153,783
Balance | Time deposits included in Short-term investments
Financial Assets:
Time deposits included in Short-term investments		60,007
Balance | Revolving credit facility | Credit Facility 2017
Financial Liabilities:
Borrowings under the 2017 Credit Facility	25,007	25,007
Estimated Fair Value
Financial Assets:
Cash equivalents:	116,212	153,783
Restricted cash	1,816	1,390
Employee loans	579	794
Estimated Fair Value | Money market funds
Financial Assets:
Cash equivalents:	116,212	153,783
Estimated Fair Value | Time deposits included in Short-term investments
Financial Assets:
Time deposits included in Short-term investments		60,007
Estimated Fair Value | Revolving credit facility | Credit Facility 2017
Financial Liabilities:
Borrowings under the 2017 Credit Facility	25,007	25,007
Estimated Fair Value | Level 1
Financial Assets:
Cash equivalents:	116,212	153,783
Restricted cash	1,816	1,390
Employee loans	0	0
Estimated Fair Value | Level 1 | Money market funds
Financial Assets:
Cash equivalents:	116,212	153,783
Estimated Fair Value | Level 1 | Time deposits included in Short-term investments
Financial Assets:
Time deposits included in Short-term investments		0
Estimated Fair Value | Level 1 | Revolving credit facility | Credit Facility 2017
Financial Liabilities:
Borrowings under the 2017 Credit Facility	0	0
Estimated Fair Value | Level 2
Financial Assets:
Cash equivalents:	0	0
Restricted cash	0	0
Employee loans	0	0
Estimated Fair Value | Level 2 | Money market funds
Financial Assets:
Cash equivalents:	0	0
Estimated Fair Value | Level 2 | Time deposits included in Short-term investments
Financial Assets:
Time deposits included in Short-term investments		60,007
Estimated Fair Value | Level 2 | Revolving credit facility | Credit Facility 2017
Financial Liabilities:
Borrowings under the 2017 Credit Facility	25,007	25,007
Estimated Fair Value | Level 3
Financial Assets:
Cash equivalents:	0	0
Restricted cash	0	0
Employee loans	579	794
Estimated Fair Value | Level 3 | Money market funds
Financial Assets:
Cash equivalents:	0	0
Estimated Fair Value | Level 3 | Time deposits included in Short-term investments
Financial Assets:
Time deposits included in Short-term investments		0
Estimated Fair Value | Level 3 | Revolving credit facility | Credit Facility 2017
Financial Liabilities:
Borrowings under the 2017 Credit Facility	$ 0	$ 0

FAIR VALUE MEASUREMENTS (Equity

FAIR VALUE MEASUREMENTS (Equity Securities Without Readily Determinable Fair Value) (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Restricted cash in Other noncurrent assets
Equity Securities without Readily Determinable Fair Value [Line Items]
Carrying amount of equity securities that do not have readily determinable fair values	$ 27.5	$ 25

DERIVATIVE FINANCIAL INSTRUME_3

DERIVATIVE FINANCIAL INSTRUMENTS (Fair Value of Derivative Instruments) (Details) - Foreign exchange contracts - USD ($)	Jun. 30, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Financial collateral (including cash collateral) required to be posted	$ 0
Designated as hedging instruments | Cash flow hedging | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Asset Derivatives	3,049,000	$ 4,955,000
Designated as hedging instruments | Cash flow hedging | Accrued expenses and other current liabilities
Derivatives, Fair Value [Line Items]
Liability Derivatives	$ 975,000	$ 243,000

LEASES (Narrative) (Details)

LEASES (Narrative) (Details) $ in Millions	Jun. 30, 2021USD ($)
Lessee, Lease, Description [Line Items]
Commitments related to operating lease agreements that have not yet commenced	$ 0.6
Minimum
Lessee, Lease, Description [Line Items]
Remaining lease term	1 month 6 days
Lease term of lease agreements that have not yet commenced	2 years
Maximum
Lessee, Lease, Description [Line Items]
Remaining lease term	9 years 10 months 24 days
Lease term of lease agreements that have not yet commenced	2 years 9 months 18 days

LEASES (Components of Lease Exp

LEASES (Components of Lease Expenses) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Lessee, Lease, Description [Line Items]
Total lease cost	$ 19,237	$ 19,699	$ 38,931	$ 41,737
Selling, general and administrative expenses
Lessee, Lease, Description [Line Items]
Operating lease cost	17,245	18,851	34,501	37,714
Variable lease cost	1,656	579	3,916	3,214
Short-term lease cost	$ 336	$ 269	$ 514	$ 809

LEASES (Supplemental Cash Flow

LEASES (Supplemental Cash Flow Information) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows used for operating leases	$ 17,774	$ 16,481	$ 35,419	$ 33,372
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	1,639	11,676	1,677	42,928
Non-cash net decrease due to lease modifications:
Operating lease right-of-use assets	(813)	(8,566)	(1,879)	(3,982)
Operating lease liabilities	$ (813)	$ (8,562)	$ (1,879)	$ (3,989)

LEASES (Weighted Average Lease

LEASES (Weighted Average Lease Terms and Discount Rates) (Details)	Jun. 30, 2021	Jun. 30, 2020
Weighted average remaining lease term, in years:
Operating leases	5 years 9 months 18 days	6 years
Weighted average discount rate:
Operating leases	2.60%	3.20%

LEASES (Maturity of Operating L

LEASES (Maturity of Operating Lease Liabilities) (Details) $ in Thousands	Jun. 30, 2021USD ($)
Leases [Abstract]
2021 (excluding six months ended June 30, 2021)	$ 31,405
2022	47,210
2023	36,440
2024	31,115
2025	22,471
Thereafter	51,040
Total lease payments	219,681
Less: imputed interest	(14,875)
Total	$ 204,806

DEBT (Details)

DEBT (Details) - Credit Facility 2017 - Revolving credit facility - USD ($)	May 24, 2017	Jun. 30, 2021	Dec. 31, 2020
Overnight Bank Funding Rate
Debt Instrument [Line Items]
Variable interest rate spread	0.50%
Daily LIBOR Rate
Debt Instrument [Line Items]
Variable interest rate spread	1.00%
U.S. dollars
Debt Instrument [Line Items]
Borrowing capacity	$ 300,000,000
Current maximum borrowing capacity	400,000,000	$ 300,000,000	$ 300,000,000
Outstanding debt		$ 25,000,000	$ 25,000,000
Interest rate		1.10%	1.20%
Available borrowing capacity		$ 275,000,000	$ 275,000,000
Other currencies, excluding U.S. dollars
Debt Instrument [Line Items]
Current maximum borrowing capacity	$ 100,000,000

REVENUES (Disaggregation of Rev

REVENUES (Disaggregation of Revenues) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation of Revenue [Line Items]
Revenues	$ 881,366	$ 632,383	$ 1,662,141	$ 1,283,742
Revenues from performance obligations satisfied in previous period	11,600		16,500
Increase (decrease) in contract with customer, liability		(3,700)		4,200
Transferred over time
Disaggregation of Revenue [Line Items]
Revenues	878,440	630,886	1,656,735	1,279,335
Transferred at a point of time
Disaggregation of Revenue [Line Items]
Revenues	2,926	1,497	5,406	4,407
Time-and-material
Disaggregation of Revenue [Line Items]
Revenues	752,513	554,860	1,417,518	1,116,039
Fixed-price
Disaggregation of Revenue [Line Items]
Revenues	123,750	72,367	235,032	158,298
Licensing
Disaggregation of Revenue [Line Items]
Revenues	4,367	2,512	8,037	5,902
Other revenues
Disaggregation of Revenue [Line Items]
Revenues	736	2,644	1,554	3,503
Financial Services
Disaggregation of Revenue [Line Items]
Revenues	193,938	127,975	362,796	259,618
Travel & Consumer
Disaggregation of Revenue [Line Items]
Revenues	171,545	107,270	310,556	226,800
Software & Hi-Tech
Disaggregation of Revenue [Line Items]
Revenues	159,162	119,485	306,226	241,334
Business Information & Media
Disaggregation of Revenue [Line Items]
Revenues	157,847	140,258	305,596	278,984
Life Sciences & Healthcare
Disaggregation of Revenue [Line Items]
Revenues	91,696	68,884	182,811	138,123
Emerging Verticals
Disaggregation of Revenue [Line Items]
Revenues	107,178	68,511	194,156	138,883
North America
Disaggregation of Revenue [Line Items]
Revenues	527,398	381,936	997,719	771,766
Europe
Disaggregation of Revenue [Line Items]
Revenues	291,281	211,064	550,653	434,121
CIS
Disaggregation of Revenue [Line Items]
Revenues	37,703	22,078	67,837	46,938
APAC
Disaggregation of Revenue [Line Items]
Revenues	24,984	17,305	45,932	30,917
North America
Disaggregation of Revenue [Line Items]
Revenues	532,022	384,829	1,006,875	775,931
North America | Transferred over time
Disaggregation of Revenue [Line Items]
Revenues	529,230	383,573	1,001,604	773,383
North America | Transferred at a point of time
Disaggregation of Revenue [Line Items]
Revenues	2,792	1,256	5,271	2,548
North America | Time-and-material
Disaggregation of Revenue [Line Items]
Revenues	466,204	348,715	884,091	705,978
North America | Fixed-price
Disaggregation of Revenue [Line Items]
Revenues	61,383	33,855	114,398	65,710
North America | Licensing
Disaggregation of Revenue [Line Items]
Revenues	4,076	1,958	7,611	3,728
North America | Other revenues
Disaggregation of Revenue [Line Items]
Revenues	359	301	775	515
North America | Financial Services
Disaggregation of Revenue [Line Items]
Revenues	83,342	47,687	153,082	95,555
North America | Travel & Consumer
Disaggregation of Revenue [Line Items]
Revenues	85,075	52,193	154,504	106,917
North America | Software & Hi-Tech
Disaggregation of Revenue [Line Items]
Revenues	134,638	100,801	260,224	202,538
North America | Business Information & Media
Disaggregation of Revenue [Line Items]
Revenues	92,379	81,481	179,584	161,701
North America | Life Sciences & Healthcare
Disaggregation of Revenue [Line Items]
Revenues	80,712	61,776	156,301	123,387
North America | Emerging Verticals
Disaggregation of Revenue [Line Items]
Revenues	55,876	40,891	103,180	85,833
North America | North America
Disaggregation of Revenue [Line Items]
Revenues	508,330	370,693	963,097	748,477
North America | Europe
Disaggregation of Revenue [Line Items]
Revenues	21,615	11,195	39,370	21,527
North America | CIS
Disaggregation of Revenue [Line Items]
Revenues	1,410	2,236	3,266	4,790
North America | APAC
Disaggregation of Revenue [Line Items]
Revenues	667	705	1,142	1,137
Europe
Disaggregation of Revenue [Line Items]
Revenues	311,949	227,305	588,653	463,638
Europe | Transferred over time
Disaggregation of Revenue [Line Items]
Revenues	311,840	227,073	588,571	463,244
Europe | Transferred at a point of time
Disaggregation of Revenue [Line Items]
Revenues	109	232	82	394
Europe | Time-and-material
Disaggregation of Revenue [Line Items]
Revenues	267,070	192,173	499,761	382,493
Europe | Fixed-price
Disaggregation of Revenue [Line Items]
Revenues	44,252	32,253	87,818	77,508
Europe | Licensing
Disaggregation of Revenue [Line Items]
Revenues	260	545	314	707
Europe | Other revenues
Disaggregation of Revenue [Line Items]
Revenues	367	2,334	760	2,930
Europe | Financial Services
Disaggregation of Revenue [Line Items]
Revenues	85,965	66,655	164,005	134,249
Europe | Travel & Consumer
Disaggregation of Revenue [Line Items]
Revenues	79,731	51,253	144,355	112,320
Europe | Software & Hi-Tech
Disaggregation of Revenue [Line Items]
Revenues	23,934	18,165	44,907	36,311
Europe | Business Information & Media
Disaggregation of Revenue [Line Items]
Revenues	65,032	58,338	125,189	116,484
Europe | Life Sciences & Healthcare
Disaggregation of Revenue [Line Items]
Revenues	10,780	7,069	26,131	14,688
Europe | Emerging Verticals
Disaggregation of Revenue [Line Items]
Revenues	46,507	25,825	84,066	49,586
Europe | North America
Disaggregation of Revenue [Line Items]
Revenues	18,036	10,835	32,699	21,254
Europe | Europe
Disaggregation of Revenue [Line Items]
Revenues	269,596	199,866	511,150	412,588
Europe | CIS
Disaggregation of Revenue [Line Items]
Revenues	0	4	14	16
Europe | APAC
Disaggregation of Revenue [Line Items]
Revenues	24,317	16,600	44,790	29,780
Russia
Disaggregation of Revenue [Line Items]
Revenues	37,395	20,249	66,613	44,173
Russia | Transferred over time
Disaggregation of Revenue [Line Items]
Revenues	37,370	20,240	66,560	42,708
Russia | Transferred at a point of time
Disaggregation of Revenue [Line Items]
Revenues	25	9	53	1,465
Russia | Time-and-material
Disaggregation of Revenue [Line Items]
Revenues	19,239	13,972	33,666	27,568
Russia | Fixed-price
Disaggregation of Revenue [Line Items]
Revenues	18,115	6,259	32,816	15,080
Russia | Licensing
Disaggregation of Revenue [Line Items]
Revenues	31	9	112	1,467
Russia | Other revenues
Disaggregation of Revenue [Line Items]
Revenues	10	9	19	58
Russia | Financial Services
Disaggregation of Revenue [Line Items]
Revenues	24,631	13,633	45,709	29,814
Russia | Travel & Consumer
Disaggregation of Revenue [Line Items]
Revenues	6,739	3,824	11,697	7,563
Russia | Software & Hi-Tech
Disaggregation of Revenue [Line Items]
Revenues	590	519	1,095	2,485
Russia | Business Information & Media
Disaggregation of Revenue [Line Items]
Revenues	436	439	823	799
Russia | Life Sciences & Healthcare
Disaggregation of Revenue [Line Items]
Revenues	204	39	379	48
Russia | Emerging Verticals
Disaggregation of Revenue [Line Items]
Revenues	4,795	1,795	6,910	3,464
Russia | North America
Disaggregation of Revenue [Line Items]
Revenues	1,032	408	1,923	2,035
Russia | Europe
Disaggregation of Revenue [Line Items]
Revenues	70	3	133	6
Russia | CIS
Disaggregation of Revenue [Line Items]
Revenues	36,293	19,838	64,557	42,132
Russia | APAC
Disaggregation of Revenue [Line Items]
Revenues	$ 0	$ 0	$ 0	$ 0

REVENUES (Revenue Expected to b

REVENUES (Revenue Expected to be Recognized in Future Related to Remaining Performance Obligations) (Details) - Fixed-price $ in Thousands	Jun. 30, 2021USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated revenues expected to be recognized in the future	$ 22,431
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated revenues expected to be recognized in the future	$ 21,439
Revenue, remaining performance obligation, expected timing of satisfaction, period	6 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated revenues expected to be recognized in the future	$ 847
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated revenues expected to be recognized in the future	$ 145
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated revenues expected to be recognized in the future	$ 0
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year

REVENUES (Contract Balances) (D

REVENUES (Contract Balances) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Change in Contract with Customer, Liability [Abstract]
Revenue recognized	$ 3,300	$ 1,300	$ 14,300	$ 7,900
Trade receivables and contract assets
Change in Contract with Customer, Liability [Abstract]
Contract assets included in Trade receivables and contract assets	29,802		29,802		$ 7,700
Accounts payable, accrued expenses and other current liabilities
Change in Contract with Customer, Liability [Abstract]
Contract liabilities	20,555		20,555		17,383
Other noncurrent liabilities
Change in Contract with Customer, Liability [Abstract]
Contract liabilities	$ 207		$ 207		$ 94

STOCK-BASED COMPENSATION (Compo

STOCK-BASED COMPENSATION (Components of Stock-Based Compensation Expenses) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 23,898	$ 19,439	$ 48,451	$ 31,320
Cost of revenues (exclusive of depreciation and amortization)
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	11,261	8,958	22,378	12,942
Selling, general and administrative expenses
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 12,637	$ 10,481	$ 26,073	$ 18,378

STOCK-BASED COMPENSATION (Stock

STOCK-BASED COMPENSATION (Stock Options Activity) (Details) - Employee Stock Option - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended
	Jun. 30, 2021
Number of Options
Beginning balance (in shares)	2,772
Options granted (in shares)	88
Options exercised (in shares)	(328)
Options forfeited/cancelled (in shares)	(5)
Ending balance (in shares)	2,527
Options vested and exercisable at period end (in shares)	2,217
Options expected to vest at period end (in shares)	286
Weighted Average Exercise Price
Options outstanding at beginning of period (in dollars per share)	$ 61.71
Options granted (in dollars per share)	395.53
Options exercised (in dollars per share)	47.76
Options forfeited/cancelled (in dollars per share)	227.25
Options outstanding at end of period (in dollars per share)	74.78
Options vested and exercisable at period end (in dollars per share)	52.50
Options expected to vest at period end (in dollars per share)	$ 232.06
Aggregate Intrinsic Value
Options outstanding at June 30, 2021	$ 1,102,051
Options vested and exercisable as of June 30, 2021	1,016,268
Options expected to vest as of June 30, 2021	$ 79,898
Weighted Average Remaining Contractual Term (in years)
Options outstanding at June 30, 2021	4 years 1 month 6 days
Options vested and exercisable as of June 30, 2021	3 years 6 months
Options expected to vest as of June 30, 2021	8 years 7 months 6 days

STOCK-BASED COMPENSATION (Sto_2

STOCK-BASED COMPENSATION (Stock Option Additional Information) (Details) - Employee Stock Option $ in Millions	6 Months Ended
	Jun. 30, 2021USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining unrecognized stock-based compensation cost	$ 22.3
Weighted-average remaining requisite service period	3 years

STOCK-BASED COMPENSATION (Restr

STOCK-BASED COMPENSATION (Restricted Stock and Restricted Stock Units Activity) (Details) shares in Thousands	6 Months Ended
	Jun. 30, 2021$ / sharesshares
Service Period | Equity Classified Award | Equity-Settled Award | Restricted Stock
Number of Shares
Unvested awards outstanding at period start (in shares) | shares	9
Awards granted (in shares) | shares	0
Awards vested (in shares) | shares	0
Awards forfeited/cancelled (in shares) | shares	0
Unvested awards outstanding at period end (in shares) | shares	9
Weighted Average Grant Date Fair Value Per Share
Unvested awards outstanding at period start (in dollars per share) | $ / shares	$ 167.18
Awards granted (in dollars per share) | $ / shares	0
Awards vested (in dollars per share) | $ / shares	0
Awards forfeited/cancelled (in dollars per share) | $ / shares	0
Unvested awards outstanding at period end (in dollars per share) | $ / shares	$ 167.18
Service Period | Equity Classified Award | Equity-Settled Award | Restricted Stock Units (RSU)
Number of Shares
Unvested awards outstanding at period start (in shares) | shares	686
Awards granted (in shares) | shares	200
Awards vested (in shares) | shares	(268)
Awards forfeited/cancelled (in shares) | shares	(18)
Unvested awards outstanding at period end (in shares) | shares	600
Weighted Average Grant Date Fair Value Per Share
Unvested awards outstanding at period start (in dollars per share) | $ / shares	$ 162.15
Awards granted (in dollars per share) | $ / shares	397.62
Awards vested (in dollars per share) | $ / shares	131.85
Awards forfeited/cancelled (in dollars per share) | $ / shares	228.28
Unvested awards outstanding at period end (in dollars per share) | $ / shares	$ 252.09
Service Period | Liability Classified Award | Cash-Settled Award | Restricted Stock Units (RSU)
Number of Shares
Unvested awards outstanding at period start (in shares) | shares	175
Awards granted (in shares) | shares	26
Awards vested (in shares) | shares	(83)
Awards forfeited/cancelled (in shares) | shares	(2)
Unvested awards outstanding at period end (in shares) | shares	116
Weighted Average Grant Date Fair Value Per Share
Unvested awards outstanding at period start (in dollars per share) | $ / shares	$ 141.16
Awards granted (in dollars per share) | $ / shares	387.84
Awards vested (in dollars per share) | $ / shares	116.11
Awards forfeited/cancelled (in dollars per share) | $ / shares	221.69
Unvested awards outstanding at period end (in dollars per share) | $ / shares	$ 213
Performance Target | Equity Classified Award | Equity-Settled Award | Restricted Stock
Number of Shares
Unvested awards outstanding at period start (in shares) | shares	9
Awards granted (in shares) | shares	0
Unvested awards outstanding at period end (in shares) | shares	9
Weighted Average Grant Date Fair Value Per Share
Unvested awards outstanding at period start (in dollars per share) | $ / shares	$ 165.87
Awards granted (in dollars per share) | $ / shares	0
Unvested awards outstanding at period end (in dollars per share) | $ / shares	$ 165.87
Performance Target | Equity Classified Award | Equity-Settled Award | Restricted Stock Units (RSU)
Number of Shares
Unvested awards outstanding at period start (in shares) | shares	21
Awards granted (in shares) | shares	1
Unvested awards outstanding at period end (in shares) | shares	22
Weighted Average Grant Date Fair Value Per Share
Unvested awards outstanding at period start (in dollars per share) | $ / shares	$ 227.16
Awards granted (in dollars per share) | $ / shares	399.99
Unvested awards outstanding at period end (in dollars per share) | $ / shares	$ 233.43

STOCK-BASED COMPENSATION (Res_2

STOCK-BASED COMPENSATION (Restricted Stock and Restricted Stock Units Additional Information) (Details) - USD ($) shares in Thousands, $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Restricted Stock | Other 2021 acquisitions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued in period (in shares)		3,800
Issuance period		12 months
Restricted Stock Units (RSU) | PolSource S.A.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued in period (in shares)		17
Restricted Stock Units (RSU) | Other 2021 acquisitions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued in period (in shares)		1
Service Period | Equity Classified Award | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining unrecognized stock-based compensation cost	$ 0.6	$ 0.6
Weighted-average remaining requisite service period		1 year 2 months 12 days
Service Period | Equity Classified Award | Restricted Stock Units (RSU)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining unrecognized stock-based compensation cost	$ 121.8	$ 121.8
Weighted-average remaining requisite service period		3 years
Service Period | Equity Classified Award | Restricted Stock Units (RSU) | PolSource S.A.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)	17
Service Period | Equity Classified Award | Restricted Stock Units (RSU) | Other 2021 acquisitions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)	11
Service Period | Equity Classified Award | Equity-Settled Award | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)		0
Service Period | Equity Classified Award | Equity-Settled Award | Restricted Stock Units (RSU)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)		200
Service Period | Liability Classified Award | Cash-Settled Award | Restricted Stock Units (RSU)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining unrecognized stock-based compensation cost	$ 41	$ 41
Weighted-average remaining requisite service period		2 years 6 months
Awards granted (in shares)		26
Performance Target | Equity-Settled Award | Restricted Stock Units (RSU) | PolSource S.A.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)	1
Shares issued in period (in shares)	5
Performance Target | Equity-Settled Award | Restricted Stock Units (RSU) | Other 2021 acquisitions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)	1
Performance Target | Equity Classified Award | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining unrecognized stock-based compensation cost	$ 0.8	$ 0.8
Weighted-average remaining requisite service period		2 years 2 months 12 days
Performance Target | Equity Classified Award | Restricted Stock Units (RSU)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining unrecognized stock-based compensation cost	2.8	$ 2.8
Weighted-average remaining requisite service period		2 years 2 months 12 days
Performance Target | Equity Classified Award | Equity-Settled Award | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)		0
Performance Target | Equity Classified Award | Equity-Settled Award | Restricted Stock Units (RSU)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)		1
Accrued compensation and benefits expenses | Service Period | Liability Classified Award | Cash-Settled Award | Restricted Stock Units (RSU)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Liability associated with RSUs	$ 13.3	$ 13.3	$ 26.8

INCOME TAXES (Details)

INCOME TAXES (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Tax Disclosure [Abstract]
Effective tax rate	6.90%	12.40%	6.00%	11.80%
Excess tax benefit	$ 21	$ 8.1	$ 42.5	$ 19.8

EARNINGS PER SHARE (Details)

EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Numerator for basic and diluted earnings per share:
Net income	$ 114,671	$ 109,046	$ 66,624	$ 85,565	$ 223,717	$ 152,189
Numerator for basic	114,671		66,624		223,717	152,189
Numerator for diluted	$ 114,671		$ 66,624		$ 223,717	$ 152,189
Denominator:
Weighted average common shares for basic earnings per share (in shares)	56,463		55,701		56,317	55,494
Net effect of dilutive stock options, restricted stock units and restricted stock awards (in shares)	2,548		2,545		2,579	2,700
Weighted average common shares for diluted earnings per share (in shares)	59,011		58,246		58,896	58,194
Net income per share:
Basic (in dollars per share)	$ 2.03		$ 1.20		$ 3.97	$ 2.74
Diluted (in dollars per share)	$ 1.94		$ 1.14		$ 3.80	$ 2.62
Anti-dilutive options not included in the calculation (in shares)	83		147		49	78

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Building Acquisition Commitments) (Details) $ in Millions	6 Months Ended
	Jun. 30, 2021USD ($)
Office Space Purchase Commitment | Ukraine
Other Commitments [Line Items]
Total commitment amount	$ 36.9

SEGMENT INFORMATION (Revenues f

SEGMENT INFORMATION (Revenues from External Customers and Operating Profit Before Unallocated Expenses) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Revenues	$ 881,366	$ 632,383	$ 1,662,141	$ 1,283,742
Segment operating profit/(loss):	125,274	83,426	232,525	170,935
Operating Segments
Segment Reporting Information [Line Items]
Segment operating profit/(loss):	167,741	111,533	313,896	222,758
North America
Segment Reporting Information [Line Items]
Revenues	532,022	384,829	1,006,875	775,931
North America | Operating Segments
Segment Reporting Information [Line Items]
Segment operating profit/(loss):	111,260	82,752	205,363	161,679
Europe
Segment Reporting Information [Line Items]
Revenues	311,949	227,305	588,653	463,638
Europe | Operating Segments
Segment Reporting Information [Line Items]
Segment operating profit/(loss):	50,452	34,426	101,525	66,205
Russia
Segment Reporting Information [Line Items]
Revenues	37,395	20,249	66,613	44,173
Russia | Operating Segments
Segment Reporting Information [Line Items]
Segment operating profit/(loss):	$ 6,029	$ (5,645)	$ 7,008	$ (5,126)

SEGMENT INFORMATION (Reconcilia

SEGMENT INFORMATION (Reconciliation of Segment Operating Profit to Consolidated Income Before Provision for Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total segment operating profit:	$ 125,274	$ 83,426	$ 232,525	$ 170,935
Stock-based compensation expense	(23,898)	(19,439)	(48,451)	(31,320)
Interest and other income, net	2,580	1,817	7,954	4,203
Foreign exchange loss	(4,693)	(9,167)	(2,394)	(2,643)
Income before provision for income taxes	123,161	76,076	238,085	172,495
Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total segment operating profit:	167,741	111,533	313,896	222,758
Unallocated Amounts
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Stock-based compensation expense	(23,898)	(19,439)	(48,451)	(31,320)
Amortization of intangibles assets	(3,961)	(2,994)	(7,101)	(6,129)
Other acquisition-related expenses	(2,099)	(148)	(4,032)	(616)
Other unallocated expenses	$ (12,509)	$ (5,526)	$ (21,787)	$ (13,758)

SEGMENT INFORMATION (Physical L

SEGMENT INFORMATION (Physical Location and Values of Long-Lived Assets) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	$ 173,545	$ 169,533
Belarus
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	77,969	73,988
Ukraine
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	27,411	30,980
Russia
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	15,506	15,036
United States
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	15,147	15,718
India
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	7,195	7,079
Hungary
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	6,112	5,365
Poland
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	5,704	5,434
Spain
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	2,828	2,799
Mexico
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	2,656	2,419
China
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	2,323	2,722
Other
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	$ 10,694	$ 7,993

SEGMENT INFORMATION (Revenues b

SEGMENT INFORMATION (Revenues by Customer Location) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 881,366	$ 632,383	$ 1,662,141	$ 1,283,742
United States
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	502,499	365,004	950,520	735,093
United Kingdom
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	112,739	82,277	206,203	174,409
Switzerland
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	63,794	46,537	131,362	93,759
Netherlands
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	36,700	27,237	69,732	53,146
Russia
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	35,767	19,448	63,423	41,409
Germany
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	25,736	19,798	47,761	39,991
Canada
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	24,455	16,585	46,290	34,505
Other locations
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 79,676	$ 55,497	$ 146,850	$ 111,430

ACCUMULATED OTHER COMPREHENSI_3

ACCUMULATED OTHER COMPREHENSIVE LOSS (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 2,063,939	$ 1,983,018	$ 1,647,482	$ 1,596,145	$ 1,983,018	$ 1,596,145
Other comprehensive income/(loss)	11,677	(15,238)	18,888	(37,887)	(3,561)	(18,999)
Ending balance	2,212,668	2,063,939	1,753,094	1,647,482	2,212,668	1,753,094
Foreign currency translation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(38,699)	(28,168)	(61,185)	(32,666)	(28,168)	(32,666)
Foreign currency translation	12,088		15,932		(1,493)	(19,400)
Income tax (expense)/benefit	(2,451)		(3,490)		599	3,323
Other comprehensive income/(loss)	9,637		12,442		(894)	(16,077)
Ending balance	(29,062)	(38,699)	(48,743)	(61,185)	(29,062)	(48,743)
Cash flow hedging instruments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(439)	3,642	(8,076)	1,292	3,642	1,292
Unrealized gain/(loss) in fair value	1,271		10,168		(6,075)	(1,260)
Actuarial losses	1,371		(1,851)		3,437	(2,511)
Income tax (expense)/benefit	(602)		(1,871)		597	849
Other comprehensive income/(loss)	2,040		6,446		(2,041)	(2,922)
Ending balance	1,601	(439)	(1,630)	(8,076)	1,601	(1,630)
Defined benefit plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(1,612)	(986)	0	0	(986)	0
Income tax (expense)/benefit	0		0		185	0
Other comprehensive income/(loss)	0		0		(626)	0
Ending balance	(1,612)	(1,612)	0	0	(1,612)	0
Actuarial losses
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Actuarial losses	0		0		(811)	0
Accumulated other comprehensive loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(40,750)	(25,512)	(69,261)	(31,374)	(25,512)	(31,374)
Other comprehensive income/(loss)	11,677	(15,238)	18,888	(37,887)
Ending balance	$ (29,073)	$ (40,750)	$ (50,373)	$ (69,261)	$ (29,073)	$ (50,373)

SUBSEQUENT EVENTS (Details)

SUBSEQUENT EVENTS (Details) $ in Millions	1 Months Ended	41 Months Ended
	Aug. 05, 2021USD ($)business	Dec. 31, 2024USD ($)
Subsequent Event
Subsequent Event [Line Items]
Number of businesses acquired | business	2
Two Acquisitions | Forecast
Subsequent Event [Line Items]
Purchase price including contingent consideration		$ 10.8
Two Acquisitions | Subsequent Event
Subsequent Event [Line Items]
Payments to acquire businesses	$ 53.7
Earn-out consideration based on achievements of certain revenue, earnings and operational targets (up to)	18.2
Two Acquisitions | Restricted Stock | Subsequent Event | Performance Target
Subsequent Event [Line Items]
Equity granted	12
Two Acquisitions | Restricted Stock Units (RSU) | Subsequent Event | Performance Target
Subsequent Event [Line Items]
Equity granted	35.3
Two Acquisitions | Restricted Stock Units (RSU) | Subsequent Event | Operational Targets And Service Based
Subsequent Event [Line Items]
Equity granted	$ 2.3

Uncategorized Items - epam-2021

Label	Element	Value
Accounting Standards Update [Extensible Enumeration]	us-gaap_AccountingStandardsUpdateExtensibleList	Accounting Standards Update 2016-13 [Member]