Business Acquisition, Equity Interest Deferred, Number of Shares

No definition available.

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- Definition

All unvested Jointech Employment Shares will be forfeited upon termination of services for cause by the Company or other than for good reason (as applicable) by either of the two former owners of the acquired business.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Business acquisition, cash consideration placed in escrow

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Consideration Placed In Escrow, Percentage

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The period of time the consideration paid for the acquisition was placed in escrow.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Consideration Placed In Escrow, Shares

+ References

No definition available.

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Estimated Future Operating Results Period, Subsequent to Acquisition Date

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
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- Definition

Numbers Of Employees From Acquired Company Accepting Positions, Business Acquisitions

+ References

No definition available.

+ Details

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Namespace Prefix:	epam_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)(4)

-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

+ Details

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- Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Namespace Prefix:
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- Details

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- Details

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- Details

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- Details

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ACQUISITIONS (Details) (USD $)	3 Months Ended		0 Months Ended
ACQUISITIONS (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Mar. 05, 2014	Apr. 30, 2014	Jun. 06, 2014	Oct. 31, 2014
Business Acquisition [Line Items]
Revenues	$ 200,045,000us-gaap_Revenues	$ 160,384,000us-gaap_Revenues
Minimum
Business Acquisition [Line Items]
Estimated Future Operating Results Period, Subsequent to Acquisition Date	7 months
Maximum
Business Acquisition [Line Items]
Estimated Future Operating Results Period, Subsequent to Acquisition Date	12 months
Netsoft
Business Acquisition [Line Items]
Cash Consideration Placed In Escrow			256,000
Consideration Placed In Escrow, Period			18 months
Netsoft \| IT professionals
Business Acquisition [Line Items]
Number of professionals			40
Jointech
Business Acquisition [Line Items]
Business Acquisition, Number of Former Owners				2
Consideration Placed In Escrow, Percentage				15.00%
Jointech \| IT professionals
Business Acquisition [Line Items]
Number of professionals				216
GGA \| IT professionals
Business Acquisition [Line Items]
Number of professionals					329
GGA \| Scientists
Business Acquisition [Line Items]
Number of professionals					126
Great Fridays Limited \| Designers
Business Acquisition [Line Items]
Number of professionals						50
Total
Business Acquisition [Line Items]
Revenues	12,800,000	400,000
Employment Shares \| Netsoft
Business Acquisition [Line Items]
Share vesting term	3 years		3 years
Stock issued or issuable, value assigned			1,017,000
Employment Shares \| Jointech
Business Acquisition [Line Items]
Share vesting term	3 years			3 years
Stock issued or issuable, value assigned				7,788,000
Consideration Placed In Escrow, Period	18 months
Employment Shares \| GGA
Business Acquisition [Line Items]
Share vesting term	3 years				3 years
Stock issued or issuable, value assigned					20,655,000
Employment Shares \| Great Fridays Limited
Business Acquisition [Line Items]
Share vesting term	3 years					3 years
Stock issued or issuable, value assigned						4,823,000
Employment Shares, Closing Shares \| Netsoft
Business Acquisition [Line Items]
Stock issued or issuable, number of shares			2,289
Employment Shares, Closing Shares \| Jointech
Business Acquisition [Line Items]
Stock issued or issuable, number of shares				89,552
Employment Shares, Closing Shares \| GGA
Business Acquisition [Line Items]
Stock issued or issuable, number of shares					262,277
Consideration Placed In Escrow, Shares					102,631
Employment Shares, Closing Shares \| Great Fridays Limited
Business Acquisition [Line Items]
Stock issued or issuable, number of shares						90,864
Consideration Placed In Escrow, Shares						28,390
Employment Shares, Earn-Out Shares \| Netsoft
Business Acquisition [Line Items]
Stock issued or issuable, number of shares			16,349
Deferred restricted shares			9,154
Employment Shares, Earn-Out Shares \| Jointech \| Maximum
Business Acquisition [Line Items]
Stock issued or issuable, value assigned				$ 5,000,000
Employment Shares, Earn-Out Shares \| Great Fridays Limited \| Maximum
Business Acquisition [Line Items]
Stock issued or issuable, number of shares						10,092